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  • richardmitnick 10:04 am on May 20, 2022 Permalink | Reply
    Tags: , , , Quantum entanglement, , "Brookhaven Lab Launches New Quantum Network Facility", The new facility already possesses one of the most advanced regional quantum networks in the U.S., Building these long-distance entanglement-on-demand capabilities will have an enormous impact on the scientific community., Enhanced optical interferometry, The facility is equipped with the state-of-the-art quantum networking equipment necessary to build these long-distance entanglement distribution networks., Quantum networking is only in its infancy., The Facility’s fiber network infrastructure is currently being expanded to cover more nodes across Long Island and the New York City metropolitan area., A rooftop construction effort is in progress and the optical system is in active development., Quantum networking offers a significantly more precise rapid and secure form of communication that will touch several key industries and applications that affect our day-to-day lives.   

    From The DOE’s Brookhaven National Laboratory: “Brookhaven Lab Launches New Quantum Network Facility” 

    From The DOE’s Brookhaven National Laboratory

    May 18, 2022
    Peter Genzer
    (631) 344-3174

    New user facility will provide infrastructure and capabilities for benchmarking performance, validating concepts, and expediting the development of the quantum internet ecosystem.

    Scientists testing equipment that will be used in the Quantum Free Space Link project, which will transmit entangled photons between a building on the Brookhaven Lab site and another more than 20 kilometers away on the Stony Brook University campus.

    The U.S. Department of Energy’s Brookhaven National Laboratory has launched a new Quantum Network Facility that will serve scientists from across the country and around the world working to advance the exciting new field of quantum communication networks.

    “Building a wide-spread, quantum-based, global communication network—the Quantum Internet—has the potential to be among the most important technological frontiers of the 21st century,” said Gabriella Carini, director of Brookhaven Lab’s Instrumentation Division. “This new facility will provide the tools and capabilities researchers need to make large-scale quantum entanglement distribution networks a reality.”

    In quantum mechanics, the physical properties of entangled particles (typically photons) remain associated, even when separated by vast distances. As a result, when measurements are performed on one side, they also affect the other. Scientists can take advantage of these properties to create a secure, long-distance quantum information network. The new facility already possesses one of the most advanced regional quantum networks in the U.S., with a team at Brookhaven Lab and Stony Brook University-SUNY recently completing the Nation’s longest quantum network, spanning 98 miles and connecting the institutions’ two campuses.

    Building these long-distance entanglement-on-demand capabilities will have an enormous impact on the scientific community. They will enable a whole new range of applications, such as enhanced optical interferometry, large line-of-sight arrays of entangled sensors, quantum networks of atomic clocks, and distributed quantum computing. The facility is equipped with the state-of-the-art quantum networking equipment necessary to build these long-distance entanglement distribution networks.

    Quantum networking is only in its infancy. Many challenges remain before the full potential of large quantum communication systems can be realized. Brookhaven’s Quantum Network Facility was formed to address all of these challenges and more. As an experimental facility, it is open to the worldwide user community. Experimental opportunities, expanding from these research efforts, will be focused on the development of foundational quantum devices, including entanglement generation and detection, and characterization of portable quantum memories with a focus on scalability through room-temperature operation.

    “One of the key aspects of this facility is that it provides the ability to integrate these quantum hardware building blocks with existing real-life inter-city fibers and characterize their performance once they are integrated with the current internet,” said Julian Martinez-Rincon, scientist in the Instrumentation Division’s Quantum Systems group. “The goal of these efforts is to perform long-distance entanglement experiments targeted at implementing new scientific applications such as distributed quantum sensing and computing, as well as to develop algorithms and protocols to remotely control a regional quantum internet testbed.”

    The facility is supported entirely by its users, including resident research programs and external users through research partnership agreements.

    The long-term vision for the facility is for it to become one of the first instances of a quantum-repeater-assisted, entanglement distribution network that will be capable of heralding and maintaining entanglement at all of its quantum nodes. The Facility’s fiber network infrastructure is currently being expanded to cover more nodes across Long Island and the New York City metropolitan area. This includes multi-purpose quantum nodes at Brookhaven Lab, Stony Brook University, and in New York City, assisted by entanglement generation and swapping nodes located in Commack and Westbury.

    At the same time, facility researchers are working to create a “free space optical link,” which will provide a direct, site-to-site entanglement distribution channel between Brookhaven Lab and Stony Brook University through open air, independent of underground infrastructure. A rooftop construction effort is in progress and the optical system is in active development, with a smaller-scale system already demonstrating a connection through free space and back with excellent efficiency.

    “Quantum networking offers a significantly more precise, rapid, and secure form of communication that will touch several key industries and applications that affect our day-to-day lives,” said Carini. “Brookhaven Lab and our partners at Stony Brook University are excited to be at the forefront of this revolution in technology.”

    See the full article here .


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    Brookhaven Campus

    One of ten national laboratories overseen and primarily funded by the The DOE Office of Science, The DOE’s Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. The Laboratory’s almost 3,000 scientists, engineers, and support staff are joined each year by more than 5,000 visiting researchers from around the world. Brookhaven is operated and managed for DOE’s Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

    Research at BNL specializes in nuclear and high energy physics, energy science and technology, environmental and bioscience, nanoscience and national security. The 5,300 acre campus contains several large research facilities, including the Relativistic Heavy Ion Collider [below] and National Synchrotron Light Source II [below]. Seven Nobel prizes have been awarded for work conducted at Brookhaven lab.

    BNL is staffed by approximately 2,750 scientists, engineers, technicians, and support personnel, and hosts 4,000 guest investigators every year. The laboratory has its own police station, fire department, and ZIP code (11973). In total, the lab spans a 5,265-acre (21 km^2) area that is mostly coterminous with the hamlet of Upton, New York. BNL is served by a rail spur operated as-needed by the New York and Atlantic Railway. Co-located with the laboratory is the Upton, New York, forecast office of the National Weather Service.

    Major programs

    Although originally conceived as a nuclear research facility, Brookhaven Lab’s mission has greatly expanded. Its foci are now:

    Nuclear and high-energy physics
    Physics and chemistry of materials
    Environmental and climate research
    Energy research
    Structural biology
    Accelerator physics


    Brookhaven National Lab was originally owned by the Atomic Energy Commission(US) and is now owned by that agency’s successor, the United States Department of Energy (DOE). DOE subcontracts the research and operation to universities and research organizations. It is currently operated by Brookhaven Science Associates LLC, which is an equal partnership of Stony Brook University and Battelle Memorial Institute. From 1947 to 1998, it was operated by Associated Universities, Inc.(AUI), but AUI lost its contract in the wake of two incidents: a 1994 fire at the facility’s high-beam flux reactor that exposed several workers to radiation and reports in 1997 of a tritium leak into the groundwater of the Long Island Central Pine Barrens on which the facility sits.


    Following World War II, the US Atomic Energy Commission was created to support government-sponsored peacetime research on atomic energy. The effort to build a nuclear reactor in the American northeast was fostered largely by physicists Isidor Isaac Rabi and Norman Foster Ramsey Jr., who during the war witnessed many of their colleagues at Columbia University leave for new remote research sites following the departure of the Manhattan Project from its campus. Their effort to house this reactor near New York City was rivalled by a similar effort at the Massachusetts Institute of Technology to have a facility near Boston, Massachusetts. Involvement was quickly solicited from representatives of northeastern universities to the south and west of New York City such that this city would be at their geographic center. In March 1946 a nonprofit corporation was established that consisted of representatives from nine major research universities — Columbia University, Cornell University, Harvard University, Johns Hopkins University, Massachusetts Institute of Technology, Princeton University, University of Pennsylvania, University of Rochester, and Yale University.

    Out of 17 considered sites in the Boston-Washington corridor, Camp Upton on Long Island was eventually chosen as the most suitable in consideration of space, transportation, and availability. The camp had been a training center from the US Army during both World War I and World War II. After the latter war, Camp Upton was deemed no longer necessary and became available for reuse. A plan was conceived to convert the military camp into a research facility.

    On March 21, 1947, the Camp Upton site was officially transferred from the U.S. War Department to the new U.S. Atomic Energy Commission (AEC), predecessor to the U.S. Department of Energy (DOE).

    Research and facilities

    Reactor history

    In 1947 construction began on the first nuclear reactor at Brookhaven, the Brookhaven Graphite Research Reactor. This reactor, which opened in 1950, was the first reactor to be constructed in the United States after World War II. The High Flux Beam Reactor operated from 1965 to 1999. In 1959 Brookhaven built the first US reactor specifically tailored to medical research, the Brookhaven Medical Research Reactor, which operated until 2000.

    Accelerator history

    In 1952 Brookhaven began using its first particle accelerator, the Cosmotron. At the time the Cosmotron was the world’s highest energy accelerator, being the first to impart more than 1 GeV of energy to a particle.

    BNL Cosmotron 1952-1966.

    The Cosmotron was retired in 1966, after it was superseded in 1960 by the new Alternating Gradient Synchrotron (AGS).

    BNL Alternating Gradient Synchrotron (AGS).

    The AGS was used in research that resulted in 3 Nobel prizes, including the discovery of the muon neutrino, the charm quark, and CP violation.

    In 1970 in BNL started the ISABELLE project to develop and build two proton intersecting storage rings.

    The groundbreaking for the project was in October 1978. In 1981, with the tunnel for the accelerator already excavated, problems with the superconducting magnets needed for the ISABELLE accelerator brought the project to a halt, and the project was eventually cancelled in 1983.

    The National Synchrotron Light Source operated from 1982 to 2014 and was involved with two Nobel Prize-winning discoveries. It has since been replaced by the National Synchrotron Light Source II. [below].

    BNL National Synchrotron Light Source.

    After ISABELLE’S cancellation, physicist at BNL proposed that the excavated tunnel and parts of the magnet assembly be used in another accelerator. In 1984 the first proposal for the accelerator now known as the Relativistic Heavy Ion Collider (RHIC)[below] was put forward. The construction got funded in 1991 and RHIC has been operational since 2000. One of the world’s only two operating heavy-ion colliders, RHIC is as of 2010 the second-highest-energy collider after the Large Hadron Collider(CH). RHIC is housed in a tunnel 2.4 miles (3.9 km) long and is visible from space.

    On January 9, 2020, It was announced by Paul Dabbar, undersecretary of the US Department of Energy Office of Science, that the BNL eRHIC design has been selected over the conceptual design put forward by DOE’s Thomas Jefferson National Accelerator Facility [Jlab] (US) as the future Electron–ion collider (EIC) in the United States.

    Brookhaven Lab Electron-Ion Collider (EIC) to be built inside the tunnel that currently houses the RHIC.

    In addition to the site selection, it was announced that the BNL EIC had acquired CD-0 from the Department of Energy. BNL’s eRHIC design proposes upgrading the existing Relativistic Heavy Ion Collider, which collides beams light to heavy ions including polarized protons, with a polarized electron facility, to be housed in the same tunnel.

    Other discoveries

    In 1958, Brookhaven scientists created one of the world’s first video games, Tennis for Two. In 1968 Brookhaven scientists patented Maglev, a transportation technology that utilizes magnetic levitation.

    Major facilities

    Relativistic Heavy Ion Collider (RHIC), which was designed to research quark–gluon plasma and the sources of proton spin. Until 2009 it was the world’s most powerful heavy ion collider. It is the only collider of spin-polarized protons.

    Center for Functional Nanomaterials (CFN), used for the study of nanoscale materials.

    BNL National Synchrotron Light Source II, Brookhaven’s newest user facility, opened in 2015 to replace the National Synchrotron Light Source (NSLS), which had operated for 30 years. NSLS was involved in the work that won the 2003 and 2009 Nobel Prize in Chemistry.

    Alternating Gradient Synchrotron, a particle accelerator that was used in three of the lab’s Nobel prizes.
    Accelerator Test Facility, generates, accelerates and monitors particle beams.
    Tandem Van de Graaff, once the world’s largest electrostatic accelerator.

    Computational Science resources, including access to a massively parallel Blue Gene series supercomputer that is among the fastest in the world for scientific research, run jointly by Brookhaven National Laboratory and Stony Brook University-SUNY.

    Interdisciplinary Science Building, with unique laboratories for studying high-temperature superconductors and other materials important for addressing energy challenges.
    NASA Space Radiation Laboratory, where scientists use beams of ions to simulate cosmic rays and assess the risks of space radiation to human space travelers and equipment.

    Off-site contributions

    It is a contributing partner to the ATLAS experiment, one of the four detectors located at the The European Organization for Nuclear Research [La Organización Europea para la Investigación Nuclear][Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH)[CERN] Large Hadron Collider(LHC).

    The European Organization for Nuclear Research [La Organización Europea para la Investigación Nuclear][Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH)[CERN] map.

    Iconic view of the European Organization for Nuclear Research [La Organización Europea para la Investigación Nuclear] [Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) [CERN] ATLAS detector.

    It is currently operating at The European Organization for Nuclear Research [La Organización Europea para la Investigación Nuclear][Organisation européenne pour la recherche nucléaire] [Europäische Organisation für Kernforschung](CH) [CERN] near Geneva, Switzerland.

    Brookhaven was also responsible for the design of the Spallation Neutron Source at DOE’s Oak Ridge National Laboratory, Tennessee.

    DOE’s Oak Ridge National Laboratory Spallation Neutron Source annotated.

    Brookhaven plays a role in a range of neutrino research projects around the world, including the Daya Bay Neutrino Experiment (CN) nuclear power plant, approximately 52 kilometers northeast of Hong Kong and 45 kilometers east of Shenzhen, China.

    Daya Bay Neutrino Experiment (CN) nuclear power plant, approximately 52 kilometers northeast of Hong Kong and 45 kilometers east of Shenzhen, China .

    BNL Center for Functional Nanomaterials.

    BNL National Synchrotron Light Source II.


    BNL Relative Heavy Ion Collider Campus.

    BNL/RHIC Star Detector.

    BNL/RHIC Phenix detector.

  • richardmitnick 2:10 pm on May 6, 2022 Permalink | Reply
    Tags: , , , , Quantum entanglement, , "It takes three to tangle- long-range quantum entanglement needs three-way interaction", A theoretical study shows that long-range entanglement can indeed survive at temperatures above absolute zero if the correct conditions are met., Long-range entanglement is central to quantum information theory., Long-range entanglement survives at a non-zero temperature only when more than three subsystems are involved.   

    From RIKEN[理](JP): “It takes three to tangle- long-range quantum entanglement needs three-way interaction” 

    RIKEN bloc

    From RIKEN[理](JP)

    May 6, 2022
    Tomotaka Kuwahara, Chief Scientist
    Analytical Quantum Complexity RIKEN Hakubi Research Team
    RIKEN Hakubi Research Teams

    Jens Wilkinson
    RIKEN International Affairs Division
    Tel: +81-(0)48-462-1225
    Email: gro-pr@riken.jp

    Infographic explaining the experiment. Credit: RIKEN.

    A theoretical study shows that long-range entanglement can indeed survive at temperatures above absolute zero if the correct conditions are met.

    Quantum computing has been earmarked as the next revolutionary step in computing. However current systems are only practically stable at temperatures close to absolute zero. A new theorem from a Japanese research collaboration provides an understanding of what types of long-range quantum entanglement survive at non-zero temperatures, revealing a fundamental aspect of macroscopic quantum phenomena and guiding the way towards further understanding of quantum systems and designing new room-temperature stable quantum devices.

    When things get small, right down to the scale of one-thousandth the width of a human hair, the laws of classical physics get replaced by those of quantum physics. The quantum world is weird and wonderful, and there is much about it that scientists are yet to understand. Large-scale or “macroscopic” quantum effects play a key role in extraordinary phenomena such as superconductivity, which is a potential game-changer in future energy transport, as well for the continued development of quantum computers.

    It is possible to observe and measure “quantumness” at this scale in particular systems with the help of long-range quantum entanglement. Quantum entanglement, which Albert Einstein once famously described as “spooky action at a distance”, occurs when a group of particles cannot be described independently from each other. This means that their properties are linked: if you can fully describe one particle, you will also know everything about the particles it is entangled with.

    Long-range entanglement is central to quantum information theory, and its further understanding could lead to a breakthrough in quantum computing technologies. However, long-range quantum entanglement is stable at specific conditions, such as between three or more parties and at temperatures close to absolute zero (-273°C). What happens to two-party entangled systems at non-zero temperatures? To answer this question, researchers from the RIKEN Center for Advanced Intelligence Project, Tokyo, and Keio University [慶應義塾大学](JP), recently presented a theoretical study in Physical Review X describing long-range entanglement at temperatures above absolute zero in bipartite systems.

    “The purpose of our study was to identify a limitation on the structure of long-range entanglement at arbitrary non-zero temperatures,” explains RIKEN Hakubi Team Leader Tomotaka Kuwahara, one of the authors of the study, who performed the research while at the RIKEN Center for Advanced Intelligence Project. “We provide simple no-go theorems that show what kinds of long-range entanglement can survive at non-zero temperatures. At temperatures above absolute zero, particles in a material vibrate and move around due to thermal energy, which acts against quantum entanglement. At arbitrary non-zero temperatures, no long-range entanglement can persist between only two subsystems.”

    The researchers’ findings are consistent with previous observations that long-range entanglement survives at a non-zero temperature only when more than three subsystems are involved. The results suggest this is a fundamental aspect of macroscopic quantum phenomena at room temperatures, and that quantum devices need to be engineered to have multipartite entangled states.

    “This result has opened the door to a deeper understanding of quantum entanglement over large distances, so this is just the beginning.”, states Keio University’s Professor Keijo Saito, the co-author of the study. “We aim to deepen our understanding of the relationship between quantum entanglement and temperature in the future. This knowledge will spark and drive the development of future quantum devices that work at room temperatures, making them practical.”

    While quantum devices that work at stable room temperatures are still in their infancy, quantum entanglement looks set to “bind” the future of this field!

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    RIKEN campus

    RIKEN [理研](JP) is Japan’s largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan. Founded in 1917, it now has about 3,000 scientists on seven campuses across Japan, including the main site at Wakō, Saitama Prefecture, just outside Tokyo. Riken is a Designated National Research and Development Institute, and was formerly an Independent Administrative Institution.
    Riken conducts research in many areas of science including physics; chemistry; biology; genomics; medical science; engineering; high-performance computing and computational science and ranging from basic research to practical applications with 485 partners worldwide. It is almost entirely funded by the Japanese government, and its annual budget is about ¥88 billion (US$790 million).

    Organizational structure:

    The main divisions of Riken are listed here. Purely administrative divisions are omitted.

    Headquarters (mostly in Wako)
    Wako Branch
    Center for Emergent Matter Science (research on new materials for reduced power consumption)
    Center for Sustainable Resource Science (research toward a sustainable society)
    Nishina Center for Accelerator-Based Science (site of the Radioactive Isotope Beam Factory, a heavy-ion accelerator complex)
    Center for Brain Science
    Center for Advanced Photonics (research on photonics including terahertz radiation)
    Research Cluster for Innovation
    Cluster for Pioneering Research (chief scientists)
    Interdisciplinary Theoretical and Mathematical Sciences Program
    Tokyo Branch
    Center for Advanced Intelligence Project (research on artificial intelligence)
    Tsukuba Branch
    BioResource Research Center
    Harima Institute
    Riken SPring-8 Center (site of the SPring-8 synchrotron and the SACLA x-ray free electron laser)

    Riken SPring-8 synchrotron, located in Hyōgo Prefecture, Japan.

    RIKEN/HARIMA (JP) X-ray Free Electron Laser
    Yokohama Branch (site of the Yokohama Nuclear magnetic resonance facility)
    Center for Sustainable Resource Science
    Center for Integrative Medical Sciences (research toward personalized medicine)
    Center for Biosystems Dynamics Research (also based in Kobe and Osaka)
    Program for Drug Discovery and Medical Technology Platform
    Structural Biology Laboratory
    Sugiyama Laboratory
    Kobe Branch
    Center for Biosystems Dynamics Research (developmental biology and nuclear medicine medical imaging techniques)
    Center for Computational Science (R-CCS, home of the K computer and The post-K (Fugaku) computer development plan)

    Riken Fujitsu K supercomputer manufactured by Fujitsu, installed at the Riken Advanced Institute for Computational Science campus in Kobe, Hyōgo Prefecture, Japan.

    Fugaku is a claimed exascale supercomputer (while only at petascale for mainstream benchmark), at the RIKEN Center for Computational Science in Kobe, Japan. It started development in 2014 as the successor to the K computer, and is officially scheduled to start operating in 2021. Fugaku made its debut in 2020, and became the fastest supercomputer in the world in the June 2020 TOP500 list, the first ever supercomputer that achieved 1 exaFLOPS. As of April 2021, Fugaku is currently the fastest supercomputer in the world.

  • richardmitnick 3:31 pm on May 3, 2022 Permalink | Reply
    Tags: "New approach may help clear hurdle to large-scale quantum computing", Already the researchers have used this architecture to generate a programmable and error-correcting quantum computer operating at 24 qubits., Another more systematic and ultimately practical way is to do something which is called quantum error correction., , Dynamically changing the layout of atoms in systems by moving and connecting them with each other in the midst of computation., Harvard-led team gets around error problems by moving and connecting atoms in mid-computation., , Quantum entanglement, , The new work builds upon the programmable quantum simulator the lab has been developing since 2017., The reason why building large-scale quantum computers is hard is because eventually you have errors. One way to reduce these errors is to just make your qubits better and better., This ability to shuffle the qubits during the computation process while preserving their quantum state dramatically expands processing capabilities and allows for self-correction of errors., This will be a major step toward building large-scale machines that leverage the bizarre characteristics of quantum mechanics and promise to bring about real-world breakthroughs.   

    From The Harvard Gazette: “New approach may help clear hurdle to large-scale quantum computing” 

    From The Harvard Gazette


    Harvard University

    May 3, 2022
    Juan Siliezar

    Dolev Bluvstein (from left), Harry Levine (on the laptop), Sepehr Ebadi, and Mikhail Lukin have created a new method for shuttling entangled atoms in a quantum processor at the forefront for building large-scale programmable quantum machines. Credit: Rose Lincoln/Harvard Staff Photographer.

    Harvard-led team gets around error problems by moving and connecting atoms in mid-computation.

    Building a plane while flying it isn’t typically a goal for most, but for a team of Harvard-led physicists that general idea might be a key to finally building large-scale quantum computers.

    Described in a new paper in Nature, the research team, which includes collaborators from QuEra Computing, The Massachusetts Institute of Technology, and The University of Innsbruck [Leopold-Franzens-Universität Innsbruck](AT), developed a new approach for processing quantum information that allows them to dynamically change the layout of atoms in their system by moving and connecting them with each other in the midst of computation.

    This ability to shuffle the qubits (the fundamental building blocks of quantum computers and the source of their massive processing power) during the computation process while preserving their quantum state dramatically expands processing capabilities and allows for self-correction of errors. Clearing this hurdle marks a major step toward building large-scale machines that leverage the bizarre characteristics of quantum mechanics and promise to bring about real-world breakthroughs in material science, communication technologies, finance, and many other fields.

    “The reason why building large-scale quantum computers is hard is because eventually you have errors,” said Mikhail Lukin, the George Vasmer Leverett Professor of Physics, co-director of the Harvard Quantum Initiative, and one of the senior authors of the study. “One way to reduce these errors is to just make your qubits better and better, but another more systematic and ultimately practical way is to do something which is called quantum error correction. That means that even if you have some errors, you can correct these errors during your computation process with redundancy.”

    The team developed a new method where any qubit can connect to any other qubit on demand. In this context, two atoms become linked and able to exchange information regardless of distance. This phenomenon is what makes quantum computers so powerful. Credit: Lukin Group.
    In classical computing, error correction is done by simply copying information from a single binary digit or bit so it’s clear when and where it failed. For example, one single bit of 0 can be copied three times to read 000. When it suddenly reads 001, it’s clear where the error is and it can be corrected. A foundational limitation of quantum mechanics is that information can’t be copied, making error correction difficult.

    The workaround the researchers implement creates a sort of backup system for the atoms and their information called a quantum error correction code. The researchers use their new technique to create many of these correction codes, including what’s known as a toric code, and it spreads them out throughout the system.

    “The key idea is we want to take a single qubit of information and spread it as nonlocally as possible across many qubits, so that if any single one of these qubits fails it doesn’t actually affect the entire state that much,” said Dolev Bluvstein, a graduate student in the Physics Department from the Lukin group who led this work.

    What makes this approach possible is that the team developed a new method where any qubit can connect to any other qubit on demand. This happens through entanglement or what Einstein called “spooky action at a distance.” In this context, two atoms become linked and able to exchange information no matter how far apart they are. This phenomenon is what makes quantum computers so powerful.

    “This entanglement can store and process an exponentially large amount of information,” Bluvstein said.

    The new work builds upon the programmable quantum simulator the lab has been developing since 2017. The researchers added new capabilities to it to allow them to move entangled atoms without losing their quantum state and while they are operating.

    Previous research in quantum systems showed that once the computation process starts, the atoms, or qubits, are stuck in their positions and only interact with qubits nearby, limiting the kinds of quantum computations and simulations that can be done between them.

    The key is that the researchers can create and store information in what are known as hyperfine qubits. The quantum state of these more robust qubits lasts significantly longer than regular qubits in their system (several seconds versus microseconds). It gives them the time they need to entangle them with other qubits, even far-away ones, so they can create complex states of entangled atoms.

    The entire process looks like this: The researchers do an initial pairing of qubits, pulse a global laser from their system to create a quantum gate that entangles these pairs, and then stores the information of the pair in the hyperfine qubits. Then, using a two-dimensional array of individually focused laser beams called optical tweezers, they move these qubits into new pairs with other atoms in the system to entangle them as well. They repeat the steps in whatever pattern they want to create different kinds of quantum circuits to perform different algorithms. Eventually, the atoms all become connected in a so-called cluster state and are spread out enough to act as backups for each other in case of an error.

    Already, Bluvstein and his colleagues have used this architecture to generate a programmable, error-correcting quantum computer operating at 24 qubits, and they plan to scale up from there. The system has become the basis for their vision of a quantum processor.

    “In the very near term, we basically can start using this new method as a kind of sandbox where we will really start developing practical methods for error correction and exploring quantum algorithms,” Lukin said. “Right now [in terms of getting to large-scale, useful quantum computers], I would say we have climbed the mountain enough to see where the top is and can now actually see a path from where we are to the highest top.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Harvard University campus

    Harvard University is the oldest institution of higher education in the United States, established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. It was named after the College’s first benefactor, the young minister John Harvard of Charlestown, who upon his death in 1638 left his library and half his estate to the institution. A statue of John Harvard stands today in front of University Hall in Harvard Yard, and is perhaps the University’s bestknown landmark.

    Harvard University has 12 degree-granting Schools in addition to the Radcliffe Institute for Advanced Study. The University has grown from nine students with a single master to an enrollment of more than 20,000 degree candidates including undergraduate, graduate, and professional students. There are more than 360,000 living alumni in the U.S. and over 190 other countries.

    The Massachusetts colonial legislature, the General Court, authorized Harvard University (US)’s founding. In its early years, Harvard College primarily trained Congregational and Unitarian clergy, although it has never been formally affiliated with any denomination. Its curriculum and student body were gradually secularized during the 18th century, and by the 19th century, Harvard University (US) had emerged as the central cultural establishment among the Boston elite. Following the American Civil War, President Charles William Eliot’s long tenure (1869–1909) transformed the college and affiliated professional schools into a modern research university; Harvard became a founding member of the Association of American Universities in 1900. James B. Conant led the university through the Great Depression and World War II; he liberalized admissions after the war.

    The university is composed of ten academic faculties plus the Radcliffe Institute for Advanced Study. Arts and Sciences offers study in a wide range of academic disciplines for undergraduates and for graduates, while the other faculties offer only graduate degrees, mostly professional. Harvard has three main campuses: the 209-acre (85 ha) Cambridge campus centered on Harvard Yard; an adjoining campus immediately across the Charles River in the Allston neighborhood of Boston; and the medical campus in Boston’s Longwood Medical Area. Harvard University’s endowment is valued at $41.9 billion, making it the largest of any academic institution. Endowment income helps enable the undergraduate college to admit students regardless of financial need and provide generous financial aid with no loans The Harvard Library is the world’s largest academic library system, comprising 79 individual libraries holding about 20.4 million items.

    Harvard University has more alumni, faculty, and researchers who have won Nobel Prizes (161) and Fields Medals (18) than any other university in the world and more alumni who have been members of the U.S. Congress, MacArthur Fellows, Rhodes Scholars (375), and Marshall Scholars (255) than any other university in the United States. Its alumni also include eight U.S. presidents and 188 living billionaires, the most of any university. Fourteen Turing Award laureates have been Harvard affiliates. Students and alumni have also won 10 Academy Awards, 48 Pulitzer Prizes, and 108 Olympic medals (46 gold), and they have founded many notable companies.


    Harvard University was established in 1636 by vote of the Great and General Court of the Massachusetts Bay Colony. In 1638, it acquired British North America’s first known printing press. In 1639, it was named Harvard College after deceased clergyman John Harvard, an alumnus of the University of Cambridge(UK) who had left the school £779 and his library of some 400 volumes. The charter creating the Harvard Corporation was granted in 1650.

    A 1643 publication gave the school’s purpose as “to advance learning and perpetuate it to posterity, dreading to leave an illiterate ministry to the churches when our present ministers shall lie in the dust.” It trained many Puritan ministers in its early years and offered a classic curriculum based on the English university model—many leaders in the colony had attended the University of Cambridge—but conformed to the tenets of Puritanism. Harvard University has never affiliated with any particular denomination, though many of its earliest graduates went on to become clergymen in Congregational and Unitarian churches.

    Increase Mather served as president from 1681 to 1701. In 1708, John Leverett became the first president who was not also a clergyman, marking a turning of the college away from Puritanism and toward intellectual independence.

    19th century

    In the 19th century, Enlightenment ideas of reason and free will were widespread among Congregational ministers, putting those ministers and their congregations in tension with more traditionalist, Calvinist parties. When Hollis Professor of Divinity David Tappan died in 1803 and President Joseph Willard died a year later, a struggle broke out over their replacements. Henry Ware was elected to the Hollis chair in 1805, and the liberal Samuel Webber was appointed to the presidency two years later, signaling the shift from the dominance of traditional ideas at Harvard to the dominance of liberal, Arminian ideas.

    Charles William Eliot, president 1869–1909, eliminated the favored position of Christianity from the curriculum while opening it to student self-direction. Though Eliot was the crucial figure in the secularization of American higher education, he was motivated not by a desire to secularize education but by Transcendentalist Unitarian convictions influenced by William Ellery Channing and Ralph Waldo Emerson.

    20th century

    In the 20th century, Harvard University’s reputation grew as a burgeoning endowment and prominent professors expanded the university’s scope. Rapid enrollment growth continued as new graduate schools were begun and the undergraduate college expanded. Radcliffe College, established in 1879 as the female counterpart of Harvard College, became one of the most prominent schools for women in the United States. Harvard University became a founding member of the Association of American Universities in 1900.

    The student body in the early decades of the century was predominantly “old-stock, high-status Protestants, especially Episcopalians, Congregationalists, and Presbyterians.” A 1923 proposal by President A. Lawrence Lowell that Jews be limited to 15% of undergraduates was rejected, but Lowell did ban blacks from freshman dormitories.

    President James B. Conant reinvigorated creative scholarship to guarantee Harvard University (US)’s preeminence among research institutions. He saw higher education as a vehicle of opportunity for the talented rather than an entitlement for the wealthy, so Conant devised programs to identify, recruit, and support talented youth. In 1943, he asked the faculty to make a definitive statement about what general education ought to be, at the secondary as well as at the college level. The resulting Report, published in 1945, was one of the most influential manifestos in 20th century American education.

    Between 1945 and 1960, admissions were opened up to bring in a more diverse group of students. No longer drawing mostly from select New England prep schools, the undergraduate college became accessible to striving middle class students from public schools; many more Jews and Catholics were admitted, but few blacks, Hispanics, or Asians. Throughout the rest of the 20th century, Harvard became more diverse.

    Harvard University’s graduate schools began admitting women in small numbers in the late 19th century. During World War II, students at Radcliffe College (which since 1879 had been paying Harvard University professors to repeat their lectures for women) began attending Harvard University classes alongside men. Women were first admitted to the medical school in 1945. Since 1971, Harvard University has controlled essentially all aspects of undergraduate admission, instruction, and housing for Radcliffe women. In 1999, Radcliffe was formally merged into Harvard University.

    21st century

    Drew Gilpin Faust, previously the dean of the Radcliffe Institute for Advanced Study, became Harvard University’s first woman president on July 1, 2007. She was succeeded by Lawrence Bacow on July 1, 2018.

  • richardmitnick 3:14 pm on April 22, 2022 Permalink | Reply
    Tags: "New hardware created by Stanford team shows a way to develop delicate quantum technologies based on tiny mechanical devices", , , , , Quantum entanglement, , , Reliable; compact; durable and efficient acoustic devices harness mechanical motion to perform useful tasks. A prime example of such a device is the mechanical oscillator., Researchers have sought to bring the benefits of mechanical systems down into the extremely small scales of the mysterious quantum realm.,   

    From Stanford University: “New hardware created by Stanford team shows a way to develop delicate quantum technologies based on tiny mechanical devices” 

    Stanford University Name

    From Stanford University

    April 21, 2022

    Written By Adam Hadhazy

    Media Contact
    Holly Alyssa MacCormick,
    Stanford School of Humanities and Sciences:

    Angled-view photograph of the fully packaged device. The top (mechanical) chip is secured facedown to the bottom (qubit) chip by an adhesive polymer. Image credit: Agnetta Cleland.

    Stanford University researchers have developed a key experimental device for future quantum physics-based technologies that borrows a page from current, everyday mechanical devices.

    Reliable, compact, durable, and efficient, acoustic devices harness mechanical motion to perform useful tasks. A prime example of such a device is the mechanical oscillator. When displaced by a force – like sound, for instance – components of the device begin moving back-and-forth about their original position. Creating this periodic motion is a handy way to keep time, filter signals, and sense motion in ubiquitous electronics, including phones, computers, and watches.

    Researchers have sought to bring the benefits of mechanical systems down into the extremely small scales of the mysterious quantum realm, where atoms delicately interact and behave in counterintuitive ways. Toward this end, Stanford researchers led by Amir Safavi-Naeini have demonstrated new capabilities by coupling tiny nanomechanical oscillators with a type of circuit that can store and process energy in the form of a qubit, or quantum “bit” of information. Using the device’s qubit, the researchers can manipulate the quantum state of mechanical oscillators, generating the kinds of quantum mechanical effects that could someday empower advanced computing and ultraprecise sensing systems.

    “With this device, we’ve shown an important next step in trying to build quantum computers and other useful quantum devices based on mechanical systems,” said Safavi-Naeini, an associate professor in the Department of Applied Physics at Stanford’s School of Humanities and Sciences. Safavi-Naeini is senior author of a new study published April 20 in the journal Nature describing the findings. “We’re in essence looking to build ‘mechanical quantum mechanical’ systems,” he said.

    Mustering quantum effects on computer chips

    The joint first authors of the study, Alex Wollack and Agnetta Cleland, both PhD candidates at Stanford, spearheaded the effort to develop this new mechanics-based quantum hardware. Using the Stanford Nano Shared Facilities on campus, the researchers worked in cleanrooms while outfitted in the body-covering white “bunny suits” worn at semiconductor manufacturing plants in order to prevent impurities from contaminating the sensitive materials in play.

    With specialized equipment, Wollack and Cleland fabricated hardware components at nanometer-scale resolutions onto two silicon computer chips. The researchers then adhered the two chips together so the components on the bottom chip faced those on the top half, sandwich-style.

    On the bottom chip, Wollack and Cleland fashioned an aluminum superconducting circuit that forms the device’s qubit. Sending microwave pulses into this circuit generates photons (particles of light), which encode a qubit of information in the device. Unlike conventional electrical devices, which store bits as voltages representing either a 0 or a 1, qubits in quantum mechanical devices can also represent weighted combinations of 0 and 1 simultaneously. This is because of the quantum mechanical phenomenon known as superposition, where a quantum system exists in multiple quantum states at once until the system is measured.

    “The way reality works at the quantum mechanical level is very different from our macroscopic experience of the world,” said Safavi-Naeini.

    The top chip contains two nanomechanical resonators formed by suspended, bridge-like crystal structures just a few tens of nanometers – or billionths of a meter – long. The crystals are made of lithium niobate, a piezoelectric material. Materials with this property can convert an electrical force into motion, which in the case of this device means the electric field conveyed by the qubit photon is converted into a quantum (or a single unit) of vibrational energy called a phonon.

    “Just like light waves, which are quantized into photons, sound waves are quantized into ‘particles’ called phonons,” said Cleland, “and by combining energy of these different forms in our device, we create a hybrid quantum technology that harnesses the advantages of both.”

    The generation of these phonons allowed each nanomechanical oscillator to act like a register, which is the smallest possible data-holding element in a computer, and with the qubit supplying the data. Like the qubit, the oscillators accordingly can also be in a superposition state – they can be both excited (representing 1) and not excited (representing 0) at the same time. The superconducting circuit enabled the researchers to prepare, read out, and modify the data stored in the registers, conceptually similar to how conventional (non-quantum) computers work.

    “The dream is to make a device that works in the same way as silicon computer chips, for example, in your phone or on a thumb drive, where registers store bits,” said Safavi-Naeini. “And while we can’t store quantum bits on a thumb drive just yet, we’re showing the same sort of thing with mechanical resonators.”

    Leveraging entanglement

    Beyond superposition, the connection between the photons and resonators in the device further leveraged another important quantum mechanical phenomenon called entanglement. What makes entangled states so counterintuitive, and also notoriously difficult to create in the lab, is that the information about the state of the system is distributed across a number of components. In these systems, it is possible to know everything about two particles together, but nothing about one of the particles observed individually. Imagine two coins that are flipped in two different places, and that are observed to land as heads or tails randomly with equal probability, but when measurements at the different places are compared, they are always correlated; that is, if one coin lands as tails, the other coin is guaranteed to land as heads.

    A single quantum of motion, or phonon, is shared between two nanomechanical devices, causing them to become entangled. Image credit: Agnetta Cleland.

    The manipulation of multiple qubits, all in superposition and entangled, is the one-two punch powering computation and sensing in sought-after quantum-based technologies. “Without superposition and lots of entanglement, you can’t build a quantum computer,” said Safavi-Naeini.

    To demonstrate these quantum effects in the experiment, the Stanford researchers generated a single qubit, stored as a photon in the circuit on the bottom chip. The circuit was then allowed to exchange energy with one of the mechanical oscillators on the top chip before transferring the remaining information to the second mechanical device. By exchanging energy in this way – first with one mechanical oscillator, and then with the second oscillator – the researchers used the circuit as a tool to quantum mechanically entangle the two mechanical resonators with each other.

    “The bizarreness of quantum mechanics is on full display here,” said Wollack. “Not only does sound come in discrete units, but a single particle of sound can be shared between the two entangled macroscopic objects, each with trillions of atoms moving – or not moving – in concert.”

    For eventually performing practical calculations, the period of sustained entanglement, or coherence, would need to be significantly longer – on the order of seconds instead of the fractions of seconds achieved so far. Superposition and entanglement are both highly delicate conditions, vulnerable to even slight disturbances in the form of heat or other energy, and accordingly endow proposed quantum sensing devices with exquisite sensitivity. But Safavi-Naeini and his co-authors believe longer coherence times can be readily achievable by honing the fabrication processes and optimizing the materials involved.

    “We’ve improved the performance of our system over the last four years by nearly 10 times every year,” said Safavi-Naeini. “Moving forward, we will continue to make concrete steps toward devising quantum mechanical devices, like computers and sensors, and bring the benefits of mechanical systems into the quantum domain.”

    Additional co-authors on the paper include Rachel G. Gruenke, Zhaoyou Wang, and Patricio Arrangoiz-Arriola of the Department of Applied Physics in Stanford’s School of Humanities and Sciences.

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Stanford University campus

    Leland and Jane Stanford founded Stanford University to “promote the public welfare by exercising an influence on behalf of humanity and civilization.” Stanford opened its doors in 1891, and more than a century later, it remains dedicated to finding solutions to the great challenges of the day and to preparing our students for leadership in today’s complex world. Stanford, is an American private research university located in Stanford, California on an 8,180-acre (3,310 ha) campus near Palo Alto. Since 1952, more than 54 Stanford faculty, staff, and alumni have won the Nobel Prize, including 19 current faculty members.

    Stanford University, officially Leland Stanford Junior University, is a private research university located in Stanford, California. Stanford was founded in 1885 by Leland and Jane Stanford in memory of their only child, Leland Stanford Jr., who had died of typhoid fever at age 15 the previous year. Stanford is consistently ranked as among the most prestigious and top universities in the world by major education publications. It is also one of the top fundraising institutions in the country, becoming the first school to raise more than a billion dollars in a year.

    Leland Stanford was a U.S. senator and former governor of California who made his fortune as a railroad tycoon. The school admitted its first students on October 1, 1891, as a coeducational and non-denominational institution. Stanford University struggled financially after the death of Leland Stanford in 1893 and again after much of the campus was damaged by the 1906 San Francisco earthquake. Following World War II, provost Frederick Terman supported faculty and graduates’ entrepreneurialism to build self-sufficient local industry in what would later be known as Silicon Valley.

    The university is organized around seven schools: three schools consisting of 40 academic departments at the undergraduate level as well as four professional schools that focus on graduate programs in law, medicine, education, and business. All schools are on the same campus. Students compete in 36 varsity sports, and the university is one of two private institutions in the Division I FBS Pac-12 Conference. It has gained 126 NCAA team championships, and Stanford has won the NACDA Directors’ Cup for 24 consecutive years, beginning in 1994–1995. In addition, Stanford students and alumni have won 270 Olympic medals including 139 gold medals.

    As of October 2020, 84 Nobel laureates, 28 Turing Award laureates, and eight Fields Medalists have been affiliated with Stanford as students, alumni, faculty, or staff. In addition, Stanford is particularly noted for its entrepreneurship and is one of the most successful universities in attracting funding for start-ups. Stanford alumni have founded numerous companies, which combined produce more than $2.7 trillion in annual revenue, roughly equivalent to the 7th largest economy in the world (as of 2020). Stanford is the alma mater of one president of the United States (Herbert Hoover), 74 living billionaires, and 17 astronauts. It is also one of the leading producers of Fulbright Scholars, Marshall Scholars, Rhodes Scholars, and members of the United States Congress.

    Stanford University was founded in 1885 by Leland and Jane Stanford, dedicated to Leland Stanford Jr, their only child. The institution opened in 1891 on Stanford’s previous Palo Alto farm.

    Jane and Leland Stanford modeled their university after the great eastern universities, most specifically Cornell University. Stanford opened being called the “Cornell of the West” in 1891 due to faculty being former Cornell affiliates (either professors, alumni, or both) including its first president, David Starr Jordan, and second president, John Casper Branner. Both Cornell and Stanford were among the first to have higher education be accessible, nonsectarian, and open to women as well as to men. Cornell is credited as one of the first American universities to adopt this radical departure from traditional education, and Stanford became an early adopter as well.

    Despite being impacted by earthquakes in both 1906 and 1989, the campus was rebuilt each time. In 1919, The Hoover Institution on War, Revolution and Peace was started by Herbert Hoover to preserve artifacts related to World War I. The Stanford Medical Center, completed in 1959, is a teaching hospital with over 800 beds. The DOE’s SLAC National Accelerator Laboratory (originally named the Stanford Linear Accelerator Center), established in 1962, performs research in particle physics.


    Most of Stanford is on an 8,180-acre (12.8 sq mi; 33.1 km^2) campus, one of the largest in the United States. It is located on the San Francisco Peninsula, in the northwest part of the Santa Clara Valley (Silicon Valley) approximately 37 miles (60 km) southeast of San Francisco and approximately 20 miles (30 km) northwest of San Jose. In 2008, 60% of this land remained undeveloped.

    Stanford’s main campus includes a census-designated place within unincorporated Santa Clara County, although some of the university land (such as the Stanford Shopping Center and the Stanford Research Park) is within the city limits of Palo Alto. The campus also includes much land in unincorporated San Mateo County (including the SLAC National Accelerator Laboratory and the Jasper Ridge Biological Preserve), as well as in the city limits of Menlo Park (Stanford Hills neighborhood), Woodside, and Portola Valley.

    Non-central campus

    Stanford currently operates in various locations outside of its central campus.

    On the founding grant:

    Jasper Ridge Biological Preserve is a 1,200-acre (490 ha) natural reserve south of the central campus owned by the university and used by wildlife biologists for research.
    SLAC National Accelerator Laboratory is a facility west of the central campus operated by the university for the Department of Energy. It contains the longest linear particle accelerator in the world, 2 miles (3.2 km) on 426 acres (172 ha) of land.
    Golf course and a seasonal lake: The university also has its own golf course and a seasonal lake (Lake Lagunita, actually an irrigation reservoir), both home to the vulnerable California tiger salamander. As of 2012 Lake Lagunita was often dry and the university had no plans to artificially fill it.

    Off the founding grant:

    Hopkins Marine Station, in Pacific Grove, California, is a marine biology research center owned by the university since 1892.
    Study abroad locations: unlike typical study abroad programs, Stanford itself operates in several locations around the world; thus, each location has Stanford faculty-in-residence and staff in addition to students, creating a “mini-Stanford”.

    Redwood City campus for many of the university’s administrative offices located in Redwood City, California, a few miles north of the main campus. In 2005, the university purchased a small, 35-acre (14 ha) campus in Midpoint Technology Park intended for staff offices; development was delayed by The Great Recession. In 2015 the university announced a development plan and the Redwood City campus opened in March 2019.

    The Bass Center in Washington, DC provides a base, including housing, for the Stanford in Washington program for undergraduates. It includes a small art gallery open to the public.

    China: Stanford Center at Peking University, housed in the Lee Jung Sen Building, is a small center for researchers and students in collaboration with Beijing University [北京大学](CN) (Kavli Institute for Astronomy and Astrophysics at Peking University(CN) (KIAA-PKU).

    Administration and organization

    Stanford is a private, non-profit university that is administered as a corporate trust governed by a privately appointed board of trustees with a maximum membership of 38. Trustees serve five-year terms (not more than two consecutive terms) and meet five times annually.[83] A new trustee is chosen by the current trustees by ballot. The Stanford trustees also oversee the Stanford Research Park, the Stanford Shopping Center, the Cantor Center for Visual Arts, Stanford University Medical Center, and many associated medical facilities (including the Lucile Packard Children’s Hospital).

    The board appoints a president to serve as the chief executive officer of the university, to prescribe the duties of professors and course of study, to manage financial and business affairs, and to appoint nine vice presidents. The provost is the chief academic and budget officer, to whom the deans of each of the seven schools report. Persis Drell became the 13th provost in February 2017.

    As of 2018, the university was organized into seven academic schools. The schools of Humanities and Sciences (27 departments), Engineering (nine departments), and Earth, Energy & Environmental Sciences (four departments) have both graduate and undergraduate programs while the Schools of Law, Medicine, Education and Business have graduate programs only. The powers and authority of the faculty are vested in the Academic Council, which is made up of tenure and non-tenure line faculty, research faculty, senior fellows in some policy centers and institutes, the president of the university, and some other academic administrators, but most matters are handled by the Faculty Senate, made up of 55 elected representatives of the faculty.

    The Associated Students of Stanford University (ASSU) is the student government for Stanford and all registered students are members. Its elected leadership consists of the Undergraduate Senate elected by the undergraduate students, the Graduate Student Council elected by the graduate students, and the President and Vice President elected as a ticket by the entire student body.

    Stanford is the beneficiary of a special clause in the California Constitution, which explicitly exempts Stanford property from taxation so long as the property is used for educational purposes.

    Endowment and donations

    The university’s endowment, managed by the Stanford Management Company, was valued at $27.7 billion as of August 31, 2019. Payouts from the Stanford endowment covered approximately 21.8% of university expenses in the 2019 fiscal year. In the 2018 NACUBO-TIAA survey of colleges and universities in the United States and Canada, only Harvard University, the University of Texas System, and Yale University had larger endowments than Stanford.

    In 2006, President John L. Hennessy launched a five-year campaign called the Stanford Challenge, which reached its $4.3 billion fundraising goal in 2009, two years ahead of time, but continued fundraising for the duration of the campaign. It concluded on December 31, 2011, having raised a total of $6.23 billion and breaking the previous campaign fundraising record of $3.88 billion held by Yale. Specifically, the campaign raised $253.7 million for undergraduate financial aid, as well as $2.33 billion for its initiative in “Seeking Solutions” to global problems, $1.61 billion for “Educating Leaders” by improving K-12 education, and $2.11 billion for “Foundation of Excellence” aimed at providing academic support for Stanford students and faculty. Funds supported 366 new fellowships for graduate students, 139 new endowed chairs for faculty, and 38 new or renovated buildings. The new funding also enabled the construction of a facility for stem cell research; a new campus for the business school; an expansion of the law school; a new Engineering Quad; a new art and art history building; an on-campus concert hall; a new art museum; and a planned expansion of the medical school, among other things. In 2012, the university raised $1.035 billion, becoming the first school to raise more than a billion dollars in a year.

    Research centers and institutes

    DOE’s SLAC National Accelerator Laboratory
    Stanford Research Institute, a center of innovation to support economic development in the region.
    Hoover Institution, a conservative American public policy institution and research institution that promotes personal and economic liberty, free enterprise, and limited government.
    Hasso Plattner Institute of Design, a multidisciplinary design school in cooperation with the Hasso Plattner Institute of University of Potsdam [Universität Potsdam](DE) that integrates product design, engineering, and business management education).
    Martin Luther King Jr. Research and Education Institute, which grew out of and still contains the Martin Luther King Jr. Papers Project.
    John S. Knight Fellowship for Professional Journalists
    Center for Ocean Solutions
    Together with UC Berkeley and UC San Francisco, Stanford is part of the Biohub, a new medical science research center founded in 2016 by a $600 million commitment from Facebook CEO and founder Mark Zuckerberg and pediatrician Priscilla Chan.

    Discoveries and innovation

    Natural sciences

    Biological synthesis of deoxyribonucleic acid (DNA) – Arthur Kornberg synthesized DNA material and won the Nobel Prize in Physiology or Medicine 1959 for his work at Stanford.
    First Transgenic organism – Stanley Cohen and Herbert Boyer were the first scientists to transplant genes from one living organism to another, a fundamental discovery for genetic engineering. Thousands of products have been developed on the basis of their work, including human growth hormone and hepatitis B vaccine.
    Laser – Arthur Leonard Schawlow shared the 1981 Nobel Prize in Physics with Nicolaas Bloembergen and Kai Siegbahn for his work on lasers.
    Nuclear magnetic resonance – Felix Bloch developed new methods for nuclear magnetic precision measurements, which are the underlying principles of the MRI.

    Computer and applied sciences

    ARPANETStanford Research Institute, formerly part of Stanford but on a separate campus, was the site of one of the four original ARPANET nodes.

    Internet—Stanford was the site where the original design of the Internet was undertaken. Vint Cerf led a research group to elaborate the design of the Transmission Control Protocol (TCP/IP) that he originally co-created with Robert E. Kahn (Bob Kahn) in 1973 and which formed the basis for the architecture of the Internet.

    Frequency modulation synthesis – John Chowning of the Music department invented the FM music synthesis algorithm in 1967, and Stanford later licensed it to Yamaha Corporation.

    Google – Google began in January 1996 as a research project by Larry Page and Sergey Brin when they were both PhD students at Stanford. They were working on the Stanford Digital Library Project (SDLP). The SDLP’s goal was “to develop the enabling technologies for a single, integrated and universal digital library” and it was funded through the National Science Foundation, among other federal agencies.

    Klystron tube – invented by the brothers Russell and Sigurd Varian at Stanford. Their prototype was completed and demonstrated successfully on August 30, 1937. Upon publication in 1939, news of the klystron immediately influenced the work of U.S. and UK researchers working on radar equipment.

    RISCARPA funded VLSI project of microprocessor design. Stanford and University of California- Berkeley are most associated with the popularization of this concept. The Stanford MIPS would go on to be commercialized as the successful MIPS architecture, while Berkeley RISC gave its name to the entire concept, commercialized as the SPARC. Another success from this era were IBM’s efforts that eventually led to the IBM POWER instruction set architecture, PowerPC, and Power ISA. As these projects matured, a wide variety of similar designs flourished in the late 1980s and especially the early 1990s, representing a major force in the Unix workstation market as well as embedded processors in laser printers, routers and similar products.
    SUN workstation – Andy Bechtolsheim designed the SUN workstation for the Stanford University Network communications project as a personal CAD workstation, which led to Sun Microsystems.

    Businesses and entrepreneurship

    Stanford is one of the most successful universities in creating companies and licensing its inventions to existing companies; it is often held up as a model for technology transfer. Stanford’s Office of Technology Licensing is responsible for commercializing university research, intellectual property, and university-developed projects.

    The university is described as having a strong venture culture in which students are encouraged, and often funded, to launch their own companies.

    Companies founded by Stanford alumni generate more than $2.7 trillion in annual revenue, equivalent to the 10th-largest economy in the world.

    Some companies closely associated with Stanford and their connections include:

    Hewlett-Packard, 1939, co-founders William R. Hewlett (B.S, PhD) and David Packard (M.S).
    Silicon Graphics, 1981, co-founders James H. Clark (Associate Professor) and several of his grad students.
    Sun Microsystems, 1982, co-founders Vinod Khosla (M.B.A), Andy Bechtolsheim (PhD) and Scott McNealy (M.B.A).
    Cisco, 1984, founders Leonard Bosack (M.S) and Sandy Lerner (M.S) who were in charge of Stanford Computer Science and Graduate School of Business computer operations groups respectively when the hardware was developed.[163]
    Yahoo!, 1994, co-founders Jerry Yang (B.S, M.S) and David Filo (M.S).
    Google, 1998, co-founders Larry Page (M.S) and Sergey Brin (M.S).
    LinkedIn, 2002, co-founders Reid Hoffman (B.S), Konstantin Guericke (B.S, M.S), Eric Lee (B.S), and Alan Liu (B.S).
    Instagram, 2010, co-founders Kevin Systrom (B.S) and Mike Krieger (B.S).
    Snapchat, 2011, co-founders Evan Spiegel and Bobby Murphy (B.S).
    Coursera, 2012, co-founders Andrew Ng (Associate Professor) and Daphne Koller (Professor, PhD).

    Student body

    Stanford enrolled 6,996 undergraduate and 10,253 graduate students as of the 2019–2020 school year. Women comprised 50.4% of undergraduates and 41.5% of graduate students. In the same academic year, the freshman retention rate was 99%.

    Stanford awarded 1,819 undergraduate degrees, 2,393 master’s degrees, 770 doctoral degrees, and 3270 professional degrees in the 2018–2019 school year. The four-year graduation rate for the class of 2017 cohort was 72.9%, and the six-year rate was 94.4%. The relatively low four-year graduation rate is a function of the university’s coterminal degree (or “coterm”) program, which allows students to earn a master’s degree as a 1-to-2-year extension of their undergraduate program.

    As of 2010, fifteen percent of undergraduates were first-generation students.


    As of 2016 Stanford had 16 male varsity sports and 20 female varsity sports, 19 club sports and about 27 intramural sports. In 1930, following a unanimous vote by the Executive Committee for the Associated Students, the athletic department adopted the mascot “Indian.” The Indian symbol and name were dropped by President Richard Lyman in 1972, after objections from Native American students and a vote by the student senate. The sports teams are now officially referred to as the “Stanford Cardinal,” referring to the deep red color, not the cardinal bird. Stanford is a member of the Pac-12 Conference in most sports, the Mountain Pacific Sports Federation in several other sports, and the America East Conference in field hockey with the participation in the inter-collegiate NCAA’s Division I FBS.

    Its traditional sports rival is the University of California, Berkeley, the neighbor to the north in the East Bay. The winner of the annual “Big Game” between the Cal and Cardinal football teams gains custody of the Stanford Axe.

    Stanford has had at least one NCAA team champion every year since the 1976–77 school year and has earned 126 NCAA national team titles since its establishment, the most among universities, and Stanford has won 522 individual national championships, the most by any university. Stanford has won the award for the top-ranked Division 1 athletic program—the NACDA Directors’ Cup, formerly known as the Sears Cup—annually for the past twenty-four straight years. Stanford athletes have won medals in every Olympic Games since 1912, winning 270 Olympic medals total, 139 of them gold. In the 2008 Summer Olympics, and 2016 Summer Olympics, Stanford won more Olympic medals than any other university in the United States. Stanford athletes won 16 medals at the 2012 Summer Olympics (12 gold, two silver and two bronze), and 27 medals at the 2016 Summer Olympics.


    The unofficial motto of Stanford, selected by President Jordan, is Die Luft der Freiheit weht. Translated from the German language, this quotation from Ulrich von Hutten means, “The wind of freedom blows.” The motto was controversial during World War I, when anything in German was suspect; at that time the university disavowed that this motto was official.
    Hail, Stanford, Hail! is the Stanford Hymn sometimes sung at ceremonies or adapted by the various University singing groups. It was written in 1892 by mechanical engineering professor Albert W. Smith and his wife, Mary Roberts Smith (in 1896 she earned the first Stanford doctorate in Economics and later became associate professor of Sociology), but was not officially adopted until after a performance on campus in March 1902 by the Mormon Tabernacle Choir.
    “Uncommon Man/Uncommon Woman”: Stanford does not award honorary degrees, but in 1953 the degree of “Uncommon Man/Uncommon Woman” was created to recognize individuals who give rare and extraordinary service to the University. Technically, this degree is awarded by the Stanford Associates, a voluntary group that is part of the university’s alumni association. As Stanford’s highest honor, it is not conferred at prescribed intervals, but only when appropriate to recognize extraordinary service. Recipients include Herbert Hoover, Bill Hewlett, Dave Packard, Lucile Packard, and John Gardner.
    Big Game events: The events in the week leading up to the Big Game vs. UC Berkeley, including Gaieties (a musical written, composed, produced, and performed by the students of Ram’s Head Theatrical Society).
    “Viennese Ball”: a formal ball with waltzes that was initially started in the 1970s by students returning from the now-closed Stanford in Vienna overseas program. It is now open to all students.
    “Full Moon on the Quad”: An annual event at Main Quad, where students gather to kiss one another starting at midnight. Typically organized by the Junior class cabinet, the festivities include live entertainment, such as music and dance performances.
    “Band Run”: An annual festivity at the beginning of the school year, where the band picks up freshmen from dorms across campus while stopping to perform at each location, culminating in a finale performance at Main Quad.
    “Mausoleum Party”: An annual Halloween Party at the Stanford Mausoleum, the final resting place of Leland Stanford Jr. and his parents. A 20-year tradition, the “Mausoleum Party” was on hiatus from 2002 to 2005 due to a lack of funding, but was revived in 2006. In 2008, it was hosted in Old Union rather than at the actual Mausoleum, because rain prohibited generators from being rented. In 2009, after fundraising efforts by the Junior Class Presidents and the ASSU Executive, the event was able to return to the Mausoleum despite facing budget cuts earlier in the year.
    Former campus traditions include the “Big Game bonfire” on Lake Lagunita (a seasonal lake usually dry in the fall), which was formally ended in 1997 because of the presence of endangered salamanders in the lake bed.

    Award laureates and scholars

    Stanford’s current community of scholars includes:

    19 Nobel Prize laureates (as of October 2020, 85 affiliates in total)
    171 members of the National Academy of Sciences
    109 members of National Academy of Engineering
    76 members of National Academy of Medicine
    288 members of the American Academy of Arts and Sciences
    19 recipients of the National Medal of Science
    1 recipient of the National Medal of Technology
    4 recipients of the National Humanities Medal
    49 members of American Philosophical Society
    56 fellows of the American Physics Society (since 1995)
    4 Pulitzer Prize winners
    31 MacArthur Fellows
    4 Wolf Foundation Prize winners
    2 ACL Lifetime Achievement Award winners
    14 AAAI fellows
    2 Presidential Medal of Freedom winners

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  • richardmitnick 4:45 pm on February 17, 2022 Permalink | Reply
    Tags: "Uncovering unexpected properties in a complex quantum material", A new study describes previously unexpected properties in a complex quantum material known as Ta2NiSe5., , Current platforms are not designed to allow multiple qubits to “talk” to one another., , , Quantum entanglement, , Symmetry plays a fundamental role in classifying phases of matter and ultimately in understanding what their downstream properties will be., Ta2NiSe5-a material system that has strong electronic correlation., The circular photogalvanic effect where light is engineered to carry an electric field and is able to probe different material properties., The researchers found that this material had broken symmetry-a finding that has significant implications on using this and other materials in future devices., , These results also provide a platform for finding and describing similar properties in other types of materials., What was hypothesized about the symmetry of Ta2NiSe5 did not align with the experimental results.   

    From Penn Today and The University of Pennsylvania School of Engineering and Applied Science (US): “Uncovering unexpected properties in a complex quantum material” 

    From Penn Today


    The University of Pennsylvania School of Engineering and Applied Science (US)


    U Penn bloc

    University of Pennsylvania

    February 16, 2022
    Erica K. Brockmeier

    A new study describes previously unexpected properties in a complex quantum material known as Ta2NiSe5. Using a novel technique developed at Penn, these findings have implications for developing future quantum devices and applications. This research, published in Science Advances, was conducted by graduate student Harshvardhan Jog and led by professor Ritesh Agarwal in collaboration with Penn’s Eugene Mele and Luminita Harnagea from the Indian Institute oF Science Education and Research Kolkata[भारतीय विज्ञान शिक्षा एवं अनुसंधान संस्थान कोलकाता](IN).

    A new study describes previously unexpected properties in a complex quantum material. Using a novel technique developed at Penn, these findings have implications for developing future quantum devices and applications.

    While the field of quantum information science has experienced progress in recent years, the widespread use of quantum computers is still limited. One challenge is the ability to only use a small number of “qubits,” the unit that performs calculations in a quantum computer, because current platforms are not designed to allow multiple qubits to “talk” to one another. In order to address this challenge, materials need to be efficient at quantum entanglement, which occurs when the states of qubits remain linked no matter their distance from one another, as well as coherence, or when a system can maintain this entanglement.

    In this study, Jog looked at Ta2NiSe5-a material system that has strong electronic correlation, making it attractive for quantum devices. Strong electronic correlation means that the material’s atomic structure is linked to its electronic properties and the strong interaction that occurs between electrons.

    To study Ta2NiSe5, Jog used a modification of a technique developed in the Agarwal lab known as the circular photogalvanic effect where light is engineered to carry an electric field and is able to probe different material properties. Developed and iterated in the past several years, this technique has revealed insights about materials such as silicon and Weyl semimetals in ways that are not possible with conventional physics and materials science experiments.

    But the challenge in this study, says Agarwal, is that this method has only been applied in materials without inversion symmetry, whereas Ta2NiSe5 does have inversion symmetry, Jog “wanted to see if this technique can be used to study materials which have inversion symmetry which, from a conventional sense, should not be producing this response,” says Agarwal.

    After connecting with Harnagea to obtain high-quality samples of Ta2NiSe5, Jog and Agarwal used a modified version of the circular photogalvanic effect and were surprised to see that there was a signal being produced. After conducting additional studies to ensure that this was not an error or an experimental artifact, they worked with Mele to develop a theory that could help explain these unexpected results.

    Mele says that the challenge with developing a theory was that what was hypothesized about the symmetry of Ta2NiSe5 did not align with the experimental results. Then, after finding a previous theory paper that suggested that the symmetry was lower than what was hypothesized, they were able to develop an explanation for these data. “We realized that, if there was a low temperature phase where the system would spontaneously shear, that would do it, suggesting that this material was deforming to this other structure,” says Mele.

    By combining their expertise from both experiment and theory, an essential component of the success of this project, the researchers found that this material had broken symmetry-a finding that has significant implications on using this and other materials in future devices. This is because symmetry plays a fundamental role in classifying phases of matter and ultimately in understanding what their downstream properties will be.

    These results also provide a platform for finding and describing similar properties in other types of materials. “Now, we have a tool that can probe very subtle symmetry breaking in crystalline materials. To understand any complex material, you have to think about symmetries because it has huge implications,” says Agarwal.

    While there remains a “long journey” before Ta2NiSe5 can be incorporated into quantum devices, the researchers are already making progress on evaluating this phenomenon further. In the laboratory, Jog and Agarwal are interested in studying additional energy levels within Ta2NiSe5, looking for potential topological properties and using the circular photogalvanic method to study other correlated systems to see if they might also have similar properties. On the theory side, Mele is studying how prevalent this phenomena might be in other material systems and is developing suggestions for other materials for experimentalists to study in the future.

    “What we’re seeing here is a response that shouldn’t occur but does under these circumstances,” says Mele. “Expanding the space of structures that you have, where you can turn on these effects that are nominally forbidden, is really important. It’s not the first time that’s ever happened in spectroscopy, but, whenever it does occur, it’s an interesting thing.”

    Along with presenting a new tool for studying complex crystals to the research community, this work also provides important insights into the types of materials that can provide two key features, entanglement and macroscopic coherence that are crucial for future quantum applications that range from medical diagnostics, low-power electronics, and sensors.

    “The long-term idea, and one of the biggest goals of condensed matter physics, is to be able to understand these highly entangled states of matter because these materials themselves can do a lot of complex simulation,” says Agarwal. “It could be that, if we can understand these types of systems, they can become natural platforms to do large-scale quantum simulation.”

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition


    The University of Pennsylvania School of Engineering and Applied Science is an undergraduate and graduate school of The University of Pennsylvania. The School offers programs that emphasize hands-on study of engineering fundamentals (with an offering of approximately 300 courses) while encouraging students to leverage the educational offerings of the broader University. Engineering students can also take advantage of research opportunities through interactions with Penn’s School of Medicine, School of Arts and Sciences and the Wharton School.

    Penn Engineering offers bachelors, masters and Ph.D. degree programs in contemporary fields of engineering study. The nationally ranked bioengineering department offers the School’s most popular undergraduate degree program. The Jerome Fisher Program in Management and Technology, offered in partnership with the Wharton School, allows students to simultaneously earn a Bachelor of Science degree in Economics as well as a Bachelor of Science degree in Engineering. SEAS also offers several masters programs, which include: Executive Master’s in Technology Management, Master of Biotechnology, Master of Computer and Information Technology, Master of Computer and Information Science and a Master of Science in Engineering in Telecommunications and Networking.


    The study of engineering at The University of Pennsylvania can be traced back to 1850 when the University trustees adopted a resolution providing for a professorship of “Chemistry as Applied to the Arts”. In 1852, the study of engineering was further formalized with the establishment of the School of Mines, Arts and Manufactures. The first Professor of Civil and Mining Engineering was appointed in 1852. The first graduate of the school received his Bachelor of Science degree in 1854. Since that time, the school has grown to six departments. In 1973, the school was renamed as the School of Engineering and Applied Science.

    The early growth of the school benefited from the generosity of two Philadelphians: John Henry Towne and Alfred Fitler Moore. Towne, a mechanical engineer and railroad developer, bequeathed the school a gift of $500,000 upon his death in 1875. The main administration building for the school still bears his name. Moore was a successful entrepreneur who made his fortune manufacturing telegraph cable. A 1923 gift from Moore established the Moore School of Electrical Engineering, which is the birthplace of the first electronic general-purpose Turing-complete digital computer, ENIAC, in 1946.

    During the latter half of the 20th century the school continued to break new ground. In 1958, Barbara G. Mandell became the first woman to enroll as an undergraduate in the School of Engineering. In 1965, the university acquired two sites that were formerly used as U.S. Army Nike Missile Base (PH 82L and PH 82R) and created the Valley Forge Research Center. In 1976, the Management and Technology Program was created. In 1990, a Bachelor of Applied Science in Biomedical Science and Bachelor of Applied Science in Environmental Science were first offered, followed by a master’s degree in Biotechnology in 1997.

    The school continues to expand with the addition of the Melvin and Claire Levine Hall for computer science in 2003, Skirkanich Hall for Bioengineering in 2006, and the Krishna P. Singh Center for Nanotechnology in 2013.


    Penn’s School of Engineering and Applied Science is organized into six departments:

    Chemical and Biomolecular Engineering
    Computer and Information Science
    Electrical and Systems Engineering
    Materials Science and Engineering
    Mechanical Engineering and Applied Mechanics

    The school’s Department of Bioengineering, originally named Biomedical Electronic Engineering, consistently garners a top-ten ranking at both the undergraduate and graduate level from U.S. News & World Report. The department also houses the George H. Stephenson Foundation Educational Laboratory & Bio-MakerSpace (aka Biomakerspace) for training undergraduate through PhD students. It is Philadelphia’s and Penn’s only Bio-MakerSpace and it is open to the Penn community, encouraging a free flow of ideas, creativity, and entrepreneurship between Bioengineering students and students throughout the university.

    Founded in 1893, the Department of Chemical and Biomolecular Engineering is “America’s oldest continuously operating degree-granting program in chemical engineering.”

    The Department of Electrical and Systems Engineering is recognized for its research in electroscience, systems science and network systems and telecommunications.

    Originally established in 1946 as the School of Metallurgical Engineering, the Materials Science and Engineering Department “includes cutting edge programs in nanoscience and nanotechnology, biomaterials, ceramics, polymers, and metals.”

    The Department of Mechanical Engineering and Applied Mechanics draws its roots from the Department of Mechanical and Electrical Engineering, which was established in 1876.

    Each department houses one or more degree programs. The Chemical and Biomolecular Engineering, Materials Science and Engineering, and Mechanical Engineering and Applied Mechanics departments each house a single degree program.

    Bioengineering houses two programs (both a Bachelor of Science in Engineering degree as well as a Bachelor of Applied Science degree). Electrical and Systems Engineering offers four Bachelor of Science in Engineering programs: Electrical Engineering, Systems Engineering, Computer Engineering, and the Networked & Social Systems Engineering, the latter two of which are co-housed with Computer and Information Science (CIS). The CIS department, like Bioengineering, offers Computer and Information Science programs under both bachelor programs. CIS also houses Digital Media Design, a program jointly operated with PennDesign.


    Penn’s School of Engineering and Applied Science is a research institution. SEAS research strives to advance science and engineering and to achieve a positive impact on society.

    U Penn campus

    Academic life at University of Pennsylvania (US) is unparalleled, with 100 countries and every U.S. state represented in one of the Ivy League’s most diverse student bodies. Consistently ranked among the top 10 universities in the country, Penn enrolls 10,000 undergraduate students and welcomes an additional 10,000 students to our world-renowned graduate and professional schools.

    Penn’s award-winning educators and scholars encourage students to pursue inquiry and discovery, follow their passions, and address the world’s most challenging problems through an interdisciplinary approach.

    The University of Pennsylvania (US) is a private Ivy League research university in Philadelphia, Pennsylvania. The university claims a founding date of 1740 and is one of the nine colonial colleges chartered prior to the U.S. Declaration of Independence. Benjamin Franklin, Penn’s founder and first president, advocated an educational program that trained leaders in commerce, government, and public service, similar to a modern liberal arts curriculum.

    Penn has four undergraduate schools as well as twelve graduate and professional schools. Schools enrolling undergraduates include the College of Arts and Sciences; the School of Engineering and Applied Science; the Wharton School; and the School of Nursing. Penn’s “One University Policy” allows students to enroll in classes in any of Penn’s twelve schools. Among its highly ranked graduate and professional schools are a law school whose first professor wrote the first draft of the United States Constitution, the first school of medicine in North America (Perelman School of Medicine, 1765), and the first collegiate business school (Wharton School, 1881).

    Penn is also home to the first “student union” building and organization (Houston Hall, 1896), the first Catholic student club in North America (Newman Center, 1893), the first double-decker college football stadium (Franklin Field, 1924 when second deck was constructed), and Morris Arboretum, the official arboretum of the Commonwealth of Pennsylvania. The first general-purpose electronic computer (ENIAC) was developed at Penn and formally dedicated in 1946. In 2019, the university had an endowment of $14.65 billion, the sixth-largest endowment of all universities in the United States, as well as a research budget of $1.02 billion. The university’s athletics program, the Quakers, fields varsity teams in 33 sports as a member of the NCAA Division I Ivy League conference.

    As of 2018, distinguished alumni and/or Trustees include three U.S. Supreme Court justices; 32 U.S. senators; 46 U.S. governors; 163 members of the U.S. House of Representatives; eight signers of the Declaration of Independence and seven signers of the U.S. Constitution (four of whom signed both representing two-thirds of the six people who signed both); 24 members of the Continental Congress; 14 foreign heads of state and two presidents of the United States, including Donald Trump. As of October 2019, 36 Nobel laureates; 80 members of the American Academy of Arts and Sciences(US); 64 billionaires; 29 Rhodes Scholars; 15 Marshall Scholars and 16 Pulitzer Prize winners have been affiliated with the university.


    The University of Pennsylvania considers itself the fourth-oldest institution of higher education in the United States, though this is contested by Princeton University(US) and Columbia(US) Universities. The university also considers itself as the first university in the United States with both undergraduate and graduate studies.

    In 1740, a group of Philadelphians joined together to erect a great preaching hall for the traveling evangelist George Whitefield, who toured the American colonies delivering open-air sermons. The building was designed and built by Edmund Woolley and was the largest building in the city at the time, drawing thousands of people the first time it was preached in. It was initially planned to serve as a charity school as well, but a lack of funds forced plans for the chapel and school to be suspended. According to Franklin’s autobiography, it was in 1743 when he first had the idea to establish an academy, “thinking the Rev. Richard Peters a fit person to superintend such an institution”. However, Peters declined a casual inquiry from Franklin and nothing further was done for another six years. In the fall of 1749, now more eager to create a school to educate future generations, Benjamin Franklin circulated a pamphlet titled Proposals Relating to the Education of Youth in Pensilvania, his vision for what he called a “Public Academy of Philadelphia”. Unlike the other colonial colleges that existed in 1749—Harvard University(US), William & Mary(US), Yale Unversity(US), and The College of New Jersey(US)—Franklin’s new school would not focus merely on education for the clergy. He advocated an innovative concept of higher education, one which would teach both the ornamental knowledge of the arts and the practical skills necessary for making a living and doing public service. The proposed program of study could have become the nation’s first modern liberal arts curriculum, although it was never implemented because Anglican priest William Smith (1727-1803), who became the first provost, and other trustees strongly preferred the traditional curriculum.

    Franklin assembled a board of trustees from among the leading citizens of Philadelphia, the first such non-sectarian board in America. At the first meeting of the 24 members of the board of trustees on November 13, 1749, the issue of where to locate the school was a prime concern. Although a lot across Sixth Street from the old Pennsylvania State House (later renamed and famously known since 1776 as “Independence Hall”), was offered without cost by James Logan, its owner, the trustees realized that the building erected in 1740, which was still vacant, would be an even better site. The original sponsors of the dormant building still owed considerable construction debts and asked Franklin’s group to assume their debts and, accordingly, their inactive trusts. On February 1, 1750, the new board took over the building and trusts of the old board. On August 13, 1751, the “Academy of Philadelphia”, using the great hall at 4th and Arch Streets, took in its first secondary students. A charity school also was chartered on July 13, 1753 by the intentions of the original “New Building” donors, although it lasted only a few years. On June 16, 1755, the “College of Philadelphia” was chartered, paving the way for the addition of undergraduate instruction. All three schools shared the same board of trustees and were considered to be part of the same institution. The first commencement exercises were held on May 17, 1757.

    The institution of higher learning was known as the College of Philadelphia from 1755 to 1779. In 1779, not trusting then-provost the Reverend William Smith’s “Loyalist” tendencies, the revolutionary State Legislature created a University of the State of Pennsylvania. The result was a schism, with Smith continuing to operate an attenuated version of the College of Philadelphia. In 1791, the legislature issued a new charter, merging the two institutions into a new University of Pennsylvania with twelve men from each institution on the new board of trustees.

    Penn has three claims to being the first university in the United States, according to university archives director Mark Frazier Lloyd: the 1765 founding of the first medical school in America made Penn the first institution to offer both “undergraduate” and professional education; the 1779 charter made it the first American institution of higher learning to take the name of “University”; and existing colleges were established as seminaries (although, as detailed earlier, Penn adopted a traditional seminary curriculum as well).

    After being located in downtown Philadelphia for more than a century, the campus was moved across the Schuylkill River to property purchased from the Blockley Almshouse in West Philadelphia in 1872, where it has since remained in an area now known as University City. Although Penn began operating as an academy or secondary school in 1751 and obtained its collegiate charter in 1755, it initially designated 1750 as its founding date; this is the year that appears on the first iteration of the university seal. Sometime later in its early history, Penn began to consider 1749 as its founding date and this year was referenced for over a century, including at the centennial celebration in 1849. In 1899, the board of trustees voted to adjust the founding date earlier again, this time to 1740, the date of “the creation of the earliest of the many educational trusts the University has taken upon itself”. The board of trustees voted in response to a three-year campaign by Penn’s General Alumni Society to retroactively revise the university’s founding date to appear older than Princeton University, which had been chartered in 1746.

    Research, innovations and discoveries

    Penn is classified as an “R1” doctoral university: “Highest research activity.” Its economic impact on the Commonwealth of Pennsylvania for 2015 amounted to $14.3 billion. Penn’s research expenditures in the 2018 fiscal year were $1.442 billion, the fourth largest in the U.S. In fiscal year 2019 Penn received $582.3 million in funding from the National Institutes of Health(US).

    In line with its well-known interdisciplinary tradition, Penn’s research centers often span two or more disciplines. In the 2010–2011 academic year alone, five interdisciplinary research centers were created or substantially expanded; these include the Center for Health-care Financing; the Center for Global Women’s Health at the Nursing School; the $13 million Morris Arboretum’s Horticulture Center; the $15 million Jay H. Baker Retailing Center at Wharton; and the $13 million Translational Research Center at Penn Medicine. With these additions, Penn now counts 165 research centers hosting a research community of over 4,300 faculty and over 1,100 postdoctoral fellows, 5,500 academic support staff and graduate student trainees. To further assist the advancement of interdisciplinary research President Amy Gutmann established the “Penn Integrates Knowledge” title awarded to selected Penn professors “whose research and teaching exemplify the integration of knowledge”. These professors hold endowed professorships and joint appointments between Penn’s schools.

    Penn is also among the most prolific producers of doctoral students. With 487 PhDs awarded in 2009, Penn ranks third in the Ivy League, only behind Columbia University(US) and Cornell University(US) (Harvard University(US) did not report data). It also has one of the highest numbers of post-doctoral appointees (933 in number for 2004–2007), ranking third in the Ivy League (behind Harvard and Yale University(US)) and tenth nationally.

    In most disciplines Penn professors’ productivity is among the highest in the nation and first in the fields of epidemiology, business, communication studies, comparative literature, languages, information science, criminal justice and criminology, social sciences and sociology. According to the National Research Council nearly three-quarters of Penn’s 41 assessed programs were placed in ranges including the top 10 rankings in their fields, with more than half of these in ranges including the top five rankings in these fields.

    Penn’s research tradition has historically been complemented by innovations that shaped higher education. In addition to establishing the first medical school; the first university teaching hospital; the first business school; and the first student union Penn was also the cradle of other significant developments. In 1852, Penn Law was the first law school in the nation to publish a law journal still in existence (then called The American Law Register, now the Penn Law Review, one of the most cited law journals in the world). Under the deanship of William Draper Lewis, the law school was also one of the first schools to emphasize legal teaching by full-time professors instead of practitioners, a system that is still followed today. The Wharton School was home to several pioneering developments in business education. It established the first research center in a business school in 1921 and the first center for entrepreneurship center in 1973 and it regularly introduced novel curricula for which BusinessWeek wrote, “Wharton is on the crest of a wave of reinvention and change in management education”.

    Several major scientific discoveries have also taken place at Penn. The university is probably best known as the place where the first general-purpose electronic computer (ENIAC) was born in 1946 at the Moore School of Electrical Engineering.

    ENIAC UPenn

    It was here also where the world’s first spelling and grammar checkers were created, as well as the popular COBOL programming language. Penn can also boast some of the most important discoveries in the field of medicine. The dialysis machine used as an artificial replacement for lost kidney function was conceived and devised out of a pressure cooker by William Inouye while he was still a student at Penn Med; the Rubella and Hepatitis B vaccines were developed at Penn; the discovery of cancer’s link with genes; cognitive therapy; Retin-A (the cream used to treat acne), Resistin; the Philadelphia gene (linked to chronic myelogenous leukemia) and the technology behind PET Scans were all discovered by Penn Med researchers. More recent gene research has led to the discovery of the genes for fragile X syndrome, the most common form of inherited mental retardation; spinal and bulbar muscular atrophy, a disorder marked by progressive muscle wasting; and Charcot–Marie–Tooth disease, a progressive neurodegenerative disease that affects the hands, feet and limbs.

    Conductive polymer was also developed at Penn by Alan J. Heeger, Alan MacDiarmid and Hideki Shirakawa, an invention that earned them the Nobel Prize in Chemistry. On faculty since 1965, Ralph L. Brinster developed the scientific basis for in vitro fertilization and the transgenic mouse at Penn and was awarded the National Medal of Science in 2010. The theory of superconductivity was also partly developed at Penn, by then-faculty member John Robert Schrieffer (along with John Bardeen and Leon Cooper). The university has also contributed major advancements in the fields of economics and management. Among the many discoveries are conjoint analysis, widely used as a predictive tool especially in market research; Simon Kuznets’s method of measuring Gross National Product; the Penn effect (the observation that consumer price levels in richer countries are systematically higher than in poorer ones) and the “Wharton Model” developed by Nobel-laureate Lawrence Klein to measure and forecast economic activity. The idea behind Health Maintenance Organizations also belonged to Penn professor Robert Eilers, who put it into practice during then-President Nixon’s health reform in the 1970s.

    International partnerships

    Students can study abroad for a semester or a year at partner institutions such as the London School of Economics(UK), University of Barcelona [Universitat de Barcelona](ES), Paris Institute of Political Studies [Institut d’études politiques de Paris](FR), University of Queensland(AU), University College London(UK), King’s College London(UK), Hebrew University of Jerusalem(IL) and University of Warwick(UK).

  • richardmitnick 10:02 am on February 15, 2022 Permalink | Reply
    Tags: "The University of Hong Kong [香港大學](HK) physicists make a stride closer in the quest for quantum materials through better measurement of quantum entanglement", 2D Moire materials such as twisted bilayer graphene are having a far-reaching role in the research of novel quantum states such as superconductivity which suffers no electronic resistance., A new algorithm to measure entanglement entropy., A new and more efficient quantum algorithm of the Monte Carlo techniques adopted by scientists to measure the Renyi entanglement entropy of objects., , Deconfined quantum criticality, DQCP: Deconfined Quantum Critical Points, , Quantum entanglement, , Renyi entanglement entropy of objects, The University of Hong Kong [香港大學](HK)   

    From The University of Hong Kong [香港大學](HK): “The University of Hong Kong [香港大學](HK) physicists make a stride closer in the quest for quantum materials through better measurement of quantum entanglement” 

    From The University of Hong Kong [香港大學](HK)

    14 Feb 2022

    Ms Casey To,
    External Relations Officer
    (Tel: 3917-4948

    Ms Cindy Chan,
    Assistant Communications Director of Faculty of Science
    Tel: 3917-5286

    Mr Jiarui ZHAO, a PhD student from Department of Physics from HKU, came up with this new algorithm of computing the quantum entanglement on a trip in the subway. Credit: HKU.

    A research team from the Department of Physics, the University of Hong Kong (HKU) has developed a new algorithm to measure entanglement entropy, advancing the exploration of more comprehensive laws in quantum mechanics, a move closer towards actualisation of application of quantum materials.

    This pivotal research work has recently been published in one of the most prestigious journals in physics – Physical Review Letters.

    Quantum materials play a vital role in propelling human advancement. The search for more novel quantum materials with exceptional properties has been pressing among the scientific and technology community.

    2D Moire materials such as twisted bilayer graphene are having a far-reaching role in the research of novel quantum states such as superconductivity which suffers no electronic resistance. They also play a role in the development of “quantum computers” that vastly outperforming the best supercomputers in existence.

    But materials can only arrive at “quantum state” , i.e. when thermal effects can no longer hinder quantum fluctuations which trigger the quantum phase transitions between different quantum states or quantum phases, at extremely low temperatures (near Absolute Zero, -273.15°C) or under exceptional high pressure. Experiments testing when and how atoms and subatomic particles of different substances “communicate and interact with each other freely through entanglement” in quantum state are therefore prohibitively costly and difficult to execute.

    The study is further complicated by the failure of classical LGW (Landau, Ginzburg, Wilson) framework to describe certain quantum phase transitions, dubbed Deconfined Quantum Critical Points (DQCP). The question then arises whether DQCP realistic lattice models can be found to resolve the inconsistencies between DQCP and QCP. Dedicated exploration of the topic produces copious numerical and theoretical works with conflicting results, and a solution remains elusive.

    Mr Jiarui ZHAO, Dr Zheng YAN, and Dr Zi Yang MENG from the Department of Physics, HKU successfully made a momentous step towards resolving the issue through the study of quantum entanglement, which marks the fundamental difference between quantum and classical physics.

    The research team developed a new and more efficient quantum algorithm of the Monte Carlo techniques adopted by scientists to measure the Renyi entanglement entropy of objects. With this new tool, they measured the Rényi entanglement entropy at the DQCP and found the scaling behaviour of the entropy, i.e. how the entropy changes with the system sizes, is in sharp contrast with the description of conventional LGW types of phase transitions.

    “Our findings helped confirm a revolutionized understanding of phase transition theory by denying the possibility of a singular theory describing DQCP. The questions raised by our work will contribute to further breakthroughs in the search for a comprehensive understanding of uncharted territory,” said Dr Zheng Yan.

    “The finding has changed our understanding of the traditional phase transition theory and raises many intriguing questions about deconfined quantum criticality. This new tool developed by us will hopefully help the process of unlocking the enigma of quantum phase transitions that has perplexed the scientific community for two decades,” said Mr Zhao Jiarui, the first author of the journal paper and a PhD student who came up with the final fixes of the algorithm.

    “This discovery will lead to a more general characterisation of the critical behaviour of novel quantum materials, and is a move closer towards actualisation of application of quantum materials which play a vital role in propelling human advancement.” Dr Meng Zi Yang remarked.

    The models

    To test the efficiency and superior power of the algorithm and demonstrate the distinct difference between the entanglement entropy of normal QCP between DQCP, the research team chose two representative models —the J1-J2 model hosting normal O(3) QCP and the J-Q3 model hosting DQCP, as shown in Image 2.

    Nonequilibrium increment algorithm

    Based on previous methods, the research team created a highly paralleled increment algorithm. As illustrated in Image 3, to the main idea of the algorithm is to divide the whole simulation task into many smaller tasks and uses massive CPUs to parallelly execute the smaller tasks thus greatly decreasing the simulation time. This improved method helped the team to simulate the two models previously mentions with high efficiency and better data quality.


    With the nonequilibrium increment method, the research team successfully obtain the second Rényi entanglement entropy SA(2) at QCP and DQCP of the two models for different system sizes. The data is shown in Image 4, and one can find from the insets that when deducting the leading term(area law contribution from the entanglement boundary) the signs of the sub-leading term clearly distinguish the QCP (negative in J1-J2 model,) and DQCP (positive in J-Q3 model). This finding rules out the possibility of the description of DQCP based on a unitary assumption and raises several intriguing questions about the theory of DQC. This discovery is likely to lead to a more general characterisation of the critical behaviour of novel quantum materials.

    See the full article here.


    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of Hong Kong [香港大學](HK) is a public research university in Hong Kong. Founded in 1911, its origins trace back to the Hong Kong College of Medicine for Chinese, which was founded in 1887. It is the oldest tertiary institution in Hong Kong. HKU was also the first university established by the British in East Asia.

    As of 2020, HKU ranks third in Asia and 22nd internationally by QS, and fourth in Asia and 35th internationally by THE. It has been commonly regarded as one of the most internationalized universities in the world as well as one of the most prestigious universities in Asia. Today, HKU has ten academic faculties with English as the main language of instruction. HKU also ranks highly in the sciences, dentistry, biomedicine, architecture, education, humanities, law, economics, business administration, linguistics, political science, and the social work and social administration.

    The University of Hong Kong was also the first team in the world to successfully isolate the coronavirus SARS-CoV, the causative agent of SARS.


    The university is a founding member of Universitas 21, an international consortium of research-led universities, and a member of the Association for Pacific Rim Universities, The Association of Commonwealth Universities, Washington University in St. Louis’s McDonnell International Scholars Academy, and many others. HKU benefits from a large operating budget supplied by high levels of government funding compared to many Western countries. In 2018/19, the Research Grants Council (RGC) granted HKU a total research funding of HK$12,127 million (41.3% of overall RGC funding), which was the highest among all universities in Hong Kong. HKU professors were among the highest paid in the world as well, having salaries far exceeding those of their US counterparts in private universities. However, with the reduction of salaries in recent years, this is no longer the case.
    HKU research output, researchers, projects, patents and theses are profiled and made publicly available in the HKU Scholars Hub. 100 members of academic staff (>10% of professoriate staff) from HKU are ranked among the world’s top 1% of scientists by the Thomson Reuters’ Essential Science Indicators, by means of the citations recorded on their publications. The university has the largest number of research postgraduate students in Hong Kong, making up approximately 10% of the total student population. All ten faculties and departments provide teaching and supervision for research (MPhil and PhD) students with administration undertaken by the Graduate School.

  • richardmitnick 11:41 am on January 26, 2022 Permalink | Reply
    Tags: "What is a quantum network?", , , Cloud supercomputing with quantum networks harnessing the power of multiple quantum computers., Connecting optical telescopes allowing multiple observatories to function as a single giant scope—an optical interferometer., Entanglement allows two qubits to become inextricably interlinked no matter how much space separates them., It may be decades before the average person has contact with a quantum network. But their applications in science may be a lot more imminent., , Quantum entanglement, , Quantum networks are like the classical networks we use in everyday life to transmit and share digital information., Quantum networks don’t exist—and many scientists in the field will tell you they’re a long way off., Quantum networks use quantum bits-or qubits-which encode information in a way that is utterly foreign to the classical way of thinking., , , Qubits use tricks from the weird world of quantum mechanics and are fundamentally different from classical computing bits., , , When quantum networks arrive they could revolutionize everyday life making unhackable communications secured for banking; medicine; navigation and more.   

    From Symmetry: “What is a quantum network?” 

    Symmetry Mag

    From Symmetry

    Mara Johnson-Groh

    Illustration by Sandbox Studio, Chicago with Ana Kova.

    As we step into the quantum age, here are four things to know about quantum networks.

    Four years, four months, and twelve days ago, a photon—a particle of light—left Proxima Centauri, the closest star to us. Just now, it finally arrived at Earth.

    Centauris Alpha, Beta, Proxima, 27 February 2012. Skatebiker.

    This photon, and others that have come with it, could reveal incredible secrets about the planets that orbit the red dwarf star—such as if they’re habitable, or even inhabited. However, with current instruments, we’re not able to tease out this information.

    That could one day change with technology called quantum networks.

    Quantum networks are like the classical networks we use in everyday life to transmit and share digital information. However, quantum networks use quantum bits-or qubits-which encode information in a way that is utterly foreign to the classical way of thinking. Qubits use tricks from the weird world of quantum mechanics and are fundamentally different from classical computing bits. And when employed on quantum networks, they are radically more powerful.

    Quantum networks don’t exist—and many scientists in the field will tell you they’re a long way off. But when they arrive, they could revolutionize everyday life, making unhackable communications secured for banking, medicine, navigation and more. We might not be there yet, but already scientists are testing the building blocks and putting together prototype systems.

    “There are breakthroughs happening all the time,” says Sophia Economou, a physics professor and quantum information expert at The Virginia Polytechnic Institute and State University (US).

    Already, basic quantum communications called quantum key distributions are helping secure transmissions made over short distances. But before quantum networks become commonplace, they’ll likely make their more public debut in scientific settings.

    As we step into the quantum age, here are four things to know about quantum networks.

    1. Quantum networks are possible because of the weird world of quantum mechanics.

    Understanding quantum networks boils down to grasping a few fundamental quantum phenomena with sci-fi sounding names: superposition, entanglement and teleportation.

    Understanding these phenomena requires stepping out of your daily experience of how the world works.

    For example, classical computer bits are either 1 or 0—like a coin flipped heads or tails or a computer’s electrical signal switched on or off. The quantum realm, though, isn’t so decisive. Qubits, which are typically photons or electrons, can be 1 or 0. But they can also simultaneously be a 1 and 0. They’re more like spinning coins, which are undecidedly both heads and tails. Only once qubits are measured do they snap into a 1 or a 0 state. This duality is called superposition, and it allows for faster completion of some computing processes.

    Furthermore, computing with qubits is more secure than with classical bits, thanks to a phenomenon known as entanglement. As described by Panagiotis Spentzouris, a scientist at The DOE’s Fermi National Accelerator Laboratory (US), “entanglement is one of the coolest and most intriguing aspects of quantum physics.”

    Entanglement allows two qubits to become inextricably interlinked no matter how much space separates them. Once entangled, two qubits can mirror one another, each fully correlated with the measurement of the other. If one qubit is switched to a 0, so will its correlated partner.

    This quirk is used to pass quantum information securely—a process known as teleportation. While this teleportation doesn’t involve moving physical objects, it does move information.

    Imagine you wanted to send a secure message to a friend connected via a quantum network.

    With a quantum network, you could send an entangled qubit to them and keep the other one for yourself. Measuring the state of the qubit would provide a key that you could use to encrypt a message sent through a non-quantum channel. Your friend’s qubit, entangled with and thus fully correlated to your qubit, would function as the key to unencrypting the received message.

    An unread quantum state can’t be copied. If a spy intercepted the qubit to steal the encryption, the qubit’s state would be interrupted, leaving a clue someone was eavesdropping.

    These types of quantum-encoded messages are already being sent. Quantum key distribution has been used for bank transfers and secure ballot result transmissions. However, this type of communication is currently practical only at short, city-scale distances.

    That’s because quantum information is delicate. Qubits are typically sent as photons using the same standard fiber-optic cables that carry the bulk of the internet. The slightest bump against the wall of a fiber optic cable, a passing photon of sunlight, and even a tiny mismatch in distances traveled can all lead to two qubits falling out of entanglement.

    2. Extended quantum networks will need special repeaters to go the distance.

    Sending information halfway around the world is much harder with quantum networks than with classical networks. In classical networks, amplifiers placed periodically along the line reemit signals, splitting a marathon into a relay race. Quantum networks can’t use amplifiers, though, because reading and reemitting qubits would disrupt their entanglement, ruining the transmission.

    Researchers are instead working on building quantum repeaters, which would be able to pass along the information without having to read the qubits. To do this, quantum repeaters would create multiple entangled pairs of qubits that would link together to form a giant entangled chain—something known as entanglement swapping. Instead of a relay race, this is more like a game of “Simon Says”, where each qubit mirrors its neighbor. The system retains its security because, just as with entanglement, if an outsider tried to copy the information, the qubits’ state would be interrupted, revealing the snooper.

    While conceptually simple, it is incredibly hard to implement.

    “Some people have demonstrated designs that would in principle be a quantum repeater, but there aren’t any deployed in a real network,” says Emilio Nanni, an assistant professor at Stanford University (US) and The DOE’s SLAC National Accelerator Laboratory (US).

    Right now, researchers are largely focusing on developing metropolitan-scale networks, which are small enough to avoid needing quantum repeaters. Spentzouris is one such researcher. He’s creating a Chicago-wide network to test network infrastructure, like entanglement swapping, which can already be done with nodes that do not use quantum repeaters. He hopes such steps will help quantum networks be ready to expand when repeaters are available.

    Other groups around the world, such as those at The Delft University of Technology [Technische Universiteit Delft](NL) and The University of Science and Technology [中国科学技术大学](CN) at Chinese Academy of Sciences [中国科学院](CN), have demonstrated longer network-like connections, including linking multiple quantum devices, entanglement over a dozen or more qubits, and using quantum teleportation over a thousand kilometers with satellite links, which suffer less loss than fiber optic cables. Though impressive, such demonstrations are still a long way from being true quantum networks.

    3. Quantum networks will work with existing networks.

    Quantum networks will ultimately need to be highly reliable and should seamlessly integrate into our lives. As such, it’s likely quantum networks will work off of a backbone of fiber optic cables, alongside our current networks and internet. To merge with our current infrastructure, quantum networks will need interfaces that can connect non-quantum systems—like your smartphone—with quantum processors and nodes.

    In his lab, Nanni and his collaborators are working to create a computer chip that could connect classical computers to a quantum network. Such chips and other classical-quantum bridges could one day allow us to send bank transfers or information effortlessly and securely via quantum networking without needing personal quantum computers.

    As researchers work toward more reliable networks, new prototypes and designs are being developed, with breakthroughs coming almost monthly. Most areas of research have designed multiple options with no clear winners.

    For example, qubits can be encoded in a multitude of ways—using their polarization states, spin states, times of arrival, the motions of trapped ions and atoms, and the states of superconductors. Some designs work incredibly well but only at supercooled temperatures, while others are compatible at room temperatures but are less reliable. Likely, future quantum networks will exist as a mash-up of such options, with different designs specialized for different applications.

    “A key challenge for quantum networks is being able to interface between many different types of quantum systems and whatever you choose to be the network,” Nanni says. “I strongly suspect that in the long run we will not really settle on just one type of device because different types of platforms have different inherent advantages.”

    4. Quantum networks will be important in scientific sensing first.
    It may be decades before the average person has contact with a quantum network. But their applications in science may be a lot more imminent.

    Early networks will likely be used for things like cloud supercomputing with quantum networks harnessing the power of multiple quantum computers. Quantum networks will also enable more precise scientific sensing, which can improve atomic clocks and make GPS more reliable.

    Astronomers are also looking to leverage quantum networks by connecting optical telescopes allowing multiple observatories to function as a single giant scope—an optical interferometer.

    Scientists already achieved something similar, in 2019, when they used the Event Horizon Telescope to create the first-ever image of a black hole.

    EHT map.

    Messier 87*, The first image of the event horizon of a black hole. This is the supermassive black hole at the center of the galaxy Messier 87. Image via The Event Horizon Telescope Collaboration released on 10 April 2019 via National Science Foundation(US).

    The EHT was not a single telescope, but rather a network of radio telescopes located around the world. Similarly, the GRAVITY instrument on ESO’s Very Large Telescope Interferometer, which consists of telescopes spread along a small hilltop, used optical interferometry to image a planet around another star in the same year.

    ESO VLTI GRAVITY instrument.

    European Southern Observatory(EU) VLTI Interferometer image at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).

    The next step is to combine optical telescopes spaced even farther apart, which would improve image resolution further. This could lead to ground-breaking discoveries about the habitability of nearby planets, dark matter and the expansion of the universe.

    “Such a resolution [that could be achieved with optical interferometers] is enough to see an area like New York City on a planet in the closest star system,” says Emil Khabiboulline, a PhD student at Harvard University (US), who published a paper [Physical Review A] describing one possible way to connect telescopes with quantum networks.

    Increasing the distance between optical telescopes, however, is a big challenge. Photons are inevitably lost during the journey to a central hub where they’re recombined, and longer distances mean more data lost.

    Quantum networks offer one solution to this problem. If the photons’ quantum information can be recorded at each telescope and passed in a network, it could massively reduce data loss. But the huge number of photons possibly amassed by an optical telescope would overwhelm the bandwidth of quantum networks as they’re now envisioned.

    One workaround is a quantum approach, proposed by Khabiboulline and others, that could compress and store the photons’ quantum information before sending it over a quantum network using a smaller number of qubits. Other groups, like researchers at The University of Sydney (AU), have proposed using quantum hard drives, devices that would store the quantum information of photons arriving at separate telescopes until they could be physically brought together and recombined.

    Regardless of the final approach, the advances first designed by astronomers and other scientists will likely trickle down into the quantum networks the public may someday use.

    “I think with a level of enthusiasm that is present in the scientific community now, over the next decade, we’re going to really make a big impact,” Nanni says.

    See the full article here .


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    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.

  • richardmitnick 9:19 pm on January 25, 2022 Permalink | Reply
    Tags: "A new language for quantum computing", , Discarding one qubit without being mindful of its entanglement with another qubit can destroy the data stored in the other jeopardizing the correctness of the program., Quantum entanglement, , Qubits: When two qubits are entangled actions on one qubit can change the value of the other even when they are physically separated - Albert Einstein’s “spooky action at a distance”., Scientists from MIT’s CSAIL aimed to do some unraveling by creating their own programming language for quantum computing called Twist., , Time crystals. Microwaves. Diamonds. What do these three disparate things have in common? Quantum computing., Twist can describe and verify which pieces of data are entangled in a quantum program through a language a classical programmer can understand.   

    From The Massachusetts Institute of Technology (US): “A new language for quantum computing” 

    MIT News

    From The Massachusetts Institute of Technology (US)

    January 24, 2022
    Rachel Gordon,MIT CSAIL-Computer Science & Artificial Intelligence Lab(US)

    While the nascent field of quantum computing can feel flashy and futuristic, quantum computers have the potential for computational breakthroughs in classically unsolvable tasks, like cryptographic and communication protocols, search, and computational physics and chemistry. Photo: Graham Carlow/IBM Corp.

    Time crystals. Microwaves. Diamonds. What do these three disparate things have in common?

    Quantum computing. Unlike traditional computers that use bits, quantum computers use qubits to encode information as zeros or ones, or both at the same time. Coupled with a cocktail of forces from quantum physics, these refrigerator-sized machines can process a whole lot of information — but they’re far from flawless. Just like our regular computers, we need to have the right programming languages to properly compute on quantum computers.

    Programming quantum computers requires awareness of something called “entanglement,” a computational multiplier for qubits of sorts, which translates to a lot of power. When two qubits are entangled actions on one qubit can change the value of the other even when they are physically separated, giving rise to Einstein’s characterization of “spooky action at a distance.” But that potency is equal parts a source of weakness. When programming, discarding one qubit without being mindful of its entanglement with another qubit can destroy the data stored in the other jeopardizing the correctness of the program.

    Scientists from MIT’s Computer Science and Artificial Intelligence (CSAIL) aimed to do some unraveling by creating their own programming language for quantum computing called Twist. Twist can describe and verify which pieces of data are entangled in a quantum program through a language a classical programmer can understand. The language uses a concept called purity, which enforces the absence of entanglement and results in more intuitive programs, with ideally fewer bugs. For example, a programmer can use Twist to say that the temporary data generated as garbage by a program is not entangled with the program’s answer, making it safe to throw away.

    While the nascent field can feel a little flashy and futuristic, with images of mammoth wiry gold machines coming to mind, quantum computers have potential for computational breakthroughs in classically unsolvable tasks, like cryptographic and communication protocols, search, and computational physics and chemistry. One of the key challenges in computational sciences is dealing with the complexity of the problem and the amount of computation needed. Whereas a classical digital computer would need a very large exponential number of bits to be able to process such a simulation, a quantum computer could do it, potentially, using a very small number of qubits — if the right programs are there.

    “Our language Twist allows a developer to write safer quantum programs by explicitly stating when a qubit must not be entangled with another,” says Charles Yuan, an MIT PhD student in electrical engineering and computer science and the lead author on a new paper [POPL 2022] about Twist. “Because understanding quantum programs requires understanding entanglement, we hope that Twist paves the way to languages that make the unique challenges of quantum computing more accessible to programmers.”

    Yuan wrote the paper alongside Chris McNally, a PhD student in electrical engineering and computer science who is affiliated with the MIT Research Laboratory of Electronics, as well as MIT Assistant Professor Michael Carbin. They presented the research at last week’s 2022 Symposium on Principles of Programming conference in Philadelphia.

    Untangling quantum entanglement

    Imagine a wooden box that has a thousand cables protruding out from one side. You can pull any cable all the way out of the box, or push it all the way in.

    After you do this for a while, the cables form a pattern of bits — zeros and ones — depending on whether they’re in or out. This box represents the memory of a classical computer. A program for this computer is a sequence of instructions for when and how to pull on the cables.

    Now imagine a second, identical-looking box. This time, you tug on a cable, and see that as it emerges, a couple of other cables are pulled back inside. Clearly, inside the box, these cables are somehow entangled with each other.

    The second box is an analogy for a quantum computer, and understanding the meaning of a quantum program requires understanding the entanglement present in its data. But detecting entanglement is not straightforward. You can’t see into the wooden box, so the best you can do is try pulling on cables and carefully reason about which are entangled. In the same way, quantum programmers today have to reason about entanglement by hand. This is where the design of Twist helps massage some of those interlaced pieces.

    The scientists designed Twist to be expressive enough to write out programs for well-known quantum algorithms and identify bugs in their implementations. To evaluate Twist’s design, they modified the programs to introduce some kind of bug that would be relatively subtle for a human programmer to detect, and showed that Twist could automatically identify the bugs and reject the programs.

    They also measured how well the programs performed in practice in terms of runtime, which had less than 4 percent overhead over existing quantum programming techniques.

    For those wary of quantum’s “seedy” reputation in its potential to break encryption systems, Yuan says it’s still not very well known to what extent quantum computers will actually be able to reach their performance promises in practice. “There’s a lot of research that’s going on in post-quantum cryptography, which exists because even quantum computing is not all-powerful. So far, there’s a very specific set of applications in which people have developed algorithms and techniques where a quantum computer can outperform classical computers.”

    An important next step is using Twist to create higher-level quantum programming languages. Most quantum programming languages today still resemble assembly language, stringing together low-level operations, without mindfulness towards things like data types and functions, and what’s typical in classical software engineering.

    “Quantum computers are error-prone and difficult to program. By introducing and reasoning about the ‘purity’ of program code, Twist takes a big step towards making quantum programming easier by guaranteeing that the quantum bits in a pure piece of code cannot be altered by bits not in that code,” says Fred Chong, the Seymour Goodman Professor of Computer Science at the University of Chicago and chief scientist at Super.tech.

    The work was supported, in part, by the MIT-IBM Watson AI Lab, the National Science Foundation, and the Office of Naval Research.

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

    MIT Seal

    USPS “Forever” postage stamps celebrating Innovation at MIT.

    MIT Campus

    The Massachusetts Institute of Technology (US) is a private land-grant research university in Cambridge, Massachusetts. The institute has an urban campus that extends more than a mile (1.6 km) alongside the Charles River. The institute also encompasses a number of major off-campus facilities such as the MIT Lincoln Laboratory (US), the MIT Bates Research and Engineering Center (US), and the Haystack Observatory (US), as well as affiliated laboratories such as the Broad Institute of MIT and Harvard(US) and Whitehead Institute (US).

    Massachusettes Institute of Technology-Haystack Observatory(US) Westford, Massachusetts, USA, Altitude 131 m (430 ft).

    Founded in 1861 in response to the increasing industrialization of the United States, Massachusetts Institute of Technology (US) adopted a European polytechnic university model and stressed laboratory instruction in applied science and engineering. It has since played a key role in the development of many aspects of modern science, engineering, mathematics, and technology, and is widely known for its innovation and academic strength. It is frequently regarded as one of the most prestigious universities in the world.

    As of December 2020, 97 Nobel laureates, 26 Turing Award winners, and 8 Fields Medalists have been affiliated with MIT as alumni, faculty members, or researchers. In addition, 58 National Medal of Science recipients, 29 National Medals of Technology and Innovation recipients, 50 MacArthur Fellows, 80 Marshall Scholars, 3 Mitchell Scholars, 22 Schwarzman Scholars, 41 astronauts, and 16 Chief Scientists of the U.S. Air Force have been affiliated with The Massachusetts Institute of Technology (US) . The university also has a strong entrepreneurial culture and MIT alumni have founded or co-founded many notable companies. Massachusetts Institute of Technology (US) is a member of the Association of American Universities (AAU).

    Foundation and vision

    In 1859, a proposal was submitted to the Massachusetts General Court to use newly filled lands in Back Bay, Boston for a “Conservatory of Art and Science”, but the proposal failed. A charter for the incorporation of the Massachusetts Institute of Technology, proposed by William Barton Rogers, was signed by John Albion Andrew, the governor of Massachusetts, on April 10, 1861.

    Rogers, a professor from the University of Virginia (US), wanted to establish an institution to address rapid scientific and technological advances. He did not wish to found a professional school, but a combination with elements of both professional and liberal education, proposing that:

    “The true and only practicable object of a polytechnic school is, as I conceive, the teaching, not of the minute details and manipulations of the arts, which can be done only in the workshop, but the inculcation of those scientific principles which form the basis and explanation of them, and along with this, a full and methodical review of all their leading processes and operations in connection with physical laws.”

    The Rogers Plan reflected the German research university model, emphasizing an independent faculty engaged in research, as well as instruction oriented around seminars and laboratories.

    Early developments

    Two days after Massachusetts Institute of Technology (US) was chartered, the first battle of the Civil War broke out. After a long delay through the war years, MIT’s first classes were held in the Mercantile Building in Boston in 1865. The new institute was founded as part of the Morrill Land-Grant Colleges Act to fund institutions “to promote the liberal and practical education of the industrial classes” and was a land-grant school. In 1863 under the same act, the Commonwealth of Massachusetts founded the Massachusetts Agricultural College, which developed as the University of Massachusetts Amherst (US)). In 1866, the proceeds from land sales went toward new buildings in the Back Bay.

    Massachusetts Institute of Technology (US) was informally called “Boston Tech”. The institute adopted the European polytechnic university model and emphasized laboratory instruction from an early date. Despite chronic financial problems, the institute saw growth in the last two decades of the 19th century under President Francis Amasa Walker. Programs in electrical, chemical, marine, and sanitary engineering were introduced, new buildings were built, and the size of the student body increased to more than one thousand.

    The curriculum drifted to a vocational emphasis, with less focus on theoretical science. The fledgling school still suffered from chronic financial shortages which diverted the attention of the MIT leadership. During these “Boston Tech” years, Massachusetts Institute of Technology (US) faculty and alumni rebuffed Harvard University (US) president (and former MIT faculty) Charles W. Eliot’s repeated attempts to merge MIT with Harvard College’s Lawrence Scientific School. There would be at least six attempts to absorb MIT into Harvard. In its cramped Back Bay location, MIT could not afford to expand its overcrowded facilities, driving a desperate search for a new campus and funding. Eventually, the MIT Corporation approved a formal agreement to merge with Harvard, over the vehement objections of MIT faculty, students, and alumni. However, a 1917 decision by the Massachusetts Supreme Judicial Court effectively put an end to the merger scheme.

    In 1916, the Massachusetts Institute of Technology (US) administration and the MIT charter crossed the Charles River on the ceremonial barge Bucentaur built for the occasion, to signify MIT’s move to a spacious new campus largely consisting of filled land on a one-mile-long (1.6 km) tract along the Cambridge side of the Charles River. The neoclassical “New Technology” campus was designed by William W. Bosworth and had been funded largely by anonymous donations from a mysterious “Mr. Smith”, starting in 1912. In January 1920, the donor was revealed to be the industrialist George Eastman of Rochester, New York, who had invented methods of film production and processing, and founded Eastman Kodak. Between 1912 and 1920, Eastman donated $20 million ($236.6 million in 2015 dollars) in cash and Kodak stock to MIT.

    Curricular reforms

    In the 1930s, President Karl Taylor Compton and Vice-President (effectively Provost) Vannevar Bush emphasized the importance of pure sciences like physics and chemistry and reduced the vocational practice required in shops and drafting studios. The Compton reforms “renewed confidence in the ability of the Institute to develop leadership in science as well as in engineering”. Unlike Ivy League schools, Massachusetts Institute of Technology (US) catered more to middle-class families, and depended more on tuition than on endowments or grants for its funding. The school was elected to the Association of American Universities (US)in 1934.

    Still, as late as 1949, the Lewis Committee lamented in its report on the state of education at Massachusetts Institute of Technology (US) that “the Institute is widely conceived as basically a vocational school”, a “partly unjustified” perception the committee sought to change. The report comprehensively reviewed the undergraduate curriculum, recommended offering a broader education, and warned against letting engineering and government-sponsored research detract from the sciences and humanities. The School of Humanities, Arts, and Social Sciences and the MIT Sloan School of Management were formed in 1950 to compete with the powerful Schools of Science and Engineering. Previously marginalized faculties in the areas of economics, management, political science, and linguistics emerged into cohesive and assertive departments by attracting respected professors and launching competitive graduate programs. The School of Humanities, Arts, and Social Sciences continued to develop under the successive terms of the more humanistically oriented presidents Howard W. Johnson and Jerome Wiesner between 1966 and 1980.

    Massachusetts Institute of Technology (US)‘s involvement in military science surged during World War II. In 1941, Vannevar Bush was appointed head of the federal Office of Scientific Research and Development and directed funding to only a select group of universities, including MIT. Engineers and scientists from across the country gathered at Massachusetts Institute of Technology (US)’s Radiation Laboratory, established in 1940 to assist the British military in developing microwave radar. The work done there significantly affected both the war and subsequent research in the area. Other defense projects included gyroscope-based and other complex control systems for gunsight, bombsight, and inertial navigation under Charles Stark Draper’s Instrumentation Laboratory; the development of a digital computer for flight simulations under Project Whirlwind; and high-speed and high-altitude photography under Harold Edgerton. By the end of the war, Massachusetts Institute of Technology (US) became the nation’s largest wartime R&D contractor (attracting some criticism of Bush), employing nearly 4000 in the Radiation Laboratory alone and receiving in excess of $100 million ($1.2 billion in 2015 dollars) before 1946. Work on defense projects continued even after then. Post-war government-sponsored research at MIT included SAGE and guidance systems for ballistic missiles and Project Apollo.

    These activities affected Massachusetts Institute of Technology (US) profoundly. A 1949 report noted the lack of “any great slackening in the pace of life at the Institute” to match the return to peacetime, remembering the “academic tranquility of the prewar years”, though acknowledging the significant contributions of military research to the increased emphasis on graduate education and rapid growth of personnel and facilities. The faculty doubled and the graduate student body quintupled during the terms of Karl Taylor Compton, president of Massachusetts Institute of Technology (US) between 1930 and 1948; James Rhyne Killian, president from 1948 to 1957; and Julius Adams Stratton, chancellor from 1952 to 1957, whose institution-building strategies shaped the expanding university. By the 1950s, Massachusetts Institute of Technology (US) no longer simply benefited the industries with which it had worked for three decades, and it had developed closer working relationships with new patrons, philanthropic foundations and the federal government.

    In late 1960s and early 1970s, student and faculty activists protested against the Vietnam War and Massachusetts Institute of Technology (US)’s defense research. In this period Massachusetts Institute of Technology (US)’s various departments were researching helicopters, smart bombs and counterinsurgency techniques for the war in Vietnam as well as guidance systems for nuclear missiles. The Union of Concerned Scientists was founded on March 4, 1969 during a meeting of faculty members and students seeking to shift the emphasis on military research toward environmental and social problems. Massachusetts Institute of Technology (US) ultimately divested itself from the Instrumentation Laboratory and moved all classified research off-campus to the MIT (US) Lincoln Laboratory facility in 1973 in response to the protests. The student body, faculty, and administration remained comparatively unpolarized during what was a tumultuous time for many other universities. Johnson was seen to be highly successful in leading his institution to “greater strength and unity” after these times of turmoil. However six Massachusetts Institute of Technology (US) students were sentenced to prison terms at this time and some former student leaders, such as Michael Albert and George Katsiaficas, are still indignant about MIT’s role in military research and its suppression of these protests. (Richard Leacock’s film, November Actions, records some of these tumultuous events.)

    In the 1980s, there was more controversy at Massachusetts Institute of Technology (US) over its involvement in SDI (space weaponry) and CBW (chemical and biological warfare) research. More recently, Massachusetts Institute of Technology (US)’s research for the military has included work on robots, drones and ‘battle suits’.

    Recent history

    Massachusetts Institute of Technology (US) has kept pace with and helped to advance the digital age. In addition to developing the predecessors to modern computing and networking technologies, students, staff, and faculty members at Project MAC, the Artificial Intelligence Laboratory, and the Tech Model Railroad Club wrote some of the earliest interactive computer video games like Spacewar! and created much of modern hacker slang and culture. Several major computer-related organizations have originated at MIT since the 1980s: Richard Stallman’s GNU Project and the subsequent Free Software Foundation were founded in the mid-1980s at the AI Lab; the MIT Media Lab was founded in 1985 by Nicholas Negroponte and Jerome Wiesner to promote research into novel uses of computer technology; the World Wide Web Consortium standards organization was founded at the Laboratory for Computer Science in 1994 by Tim Berners-Lee; the MIT OpenCourseWare project has made course materials for over 2,000 Massachusetts Institute of Technology (US) classes available online free of charge since 2002; and the One Laptop per Child initiative to expand computer education and connectivity to children worldwide was launched in 2005.

    Massachusetts Institute of Technology (US) was named a sea-grant college in 1976 to support its programs in oceanography and marine sciences and was named a space-grant college in 1989 to support its aeronautics and astronautics programs. Despite diminishing government financial support over the past quarter century, MIT launched several successful development campaigns to significantly expand the campus: new dormitories and athletics buildings on west campus; the Tang Center for Management Education; several buildings in the northeast corner of campus supporting research into biology, brain and cognitive sciences, genomics, biotechnology, and cancer research; and a number of new “backlot” buildings on Vassar Street including the Stata Center. Construction on campus in the 2000s included expansions of the Media Lab, the Sloan School’s eastern campus, and graduate residences in the northwest. In 2006, President Hockfield launched the MIT Energy Research Council to investigate the interdisciplinary challenges posed by increasing global energy consumption.

    In 2001, inspired by the open source and open access movements, Massachusetts Institute of Technology (US) launched OpenCourseWare to make the lecture notes, problem sets, syllabi, exams, and lectures from the great majority of its courses available online for no charge, though without any formal accreditation for coursework completed. While the cost of supporting and hosting the project is high, OCW expanded in 2005 to include other universities as a part of the OpenCourseWare Consortium, which currently includes more than 250 academic institutions with content available in at least six languages. In 2011, Massachusetts Institute of Technology (US) announced it would offer formal certification (but not credits or degrees) to online participants completing coursework in its “MITx” program, for a modest fee. The “edX” online platform supporting MITx was initially developed in partnership with Harvard and its analogous “Harvardx” initiative. The courseware platform is open source, and other universities have already joined and added their own course content. In March 2009 the Massachusetts Institute of Technology (US) faculty adopted an open-access policy to make its scholarship publicly accessible online.

    Massachusetts Institute of Technology (US) has its own police force. Three days after the Boston Marathon bombing of April 2013, MIT Police patrol officer Sean Collier was fatally shot by the suspects Dzhokhar and Tamerlan Tsarnaev, setting off a violent manhunt that shut down the campus and much of the Boston metropolitan area for a day. One week later, Collier’s memorial service was attended by more than 10,000 people, in a ceremony hosted by the Massachusetts Institute of Technology (US) community with thousands of police officers from the New England region and Canada. On November 25, 2013, Massachusetts Institute of Technology (US) announced the creation of the Collier Medal, to be awarded annually to “an individual or group that embodies the character and qualities that Officer Collier exhibited as a member of the Massachusetts Institute of Technology (US) community and in all aspects of his life”. The announcement further stated that “Future recipients of the award will include those whose contributions exceed the boundaries of their profession, those who have contributed to building bridges across the community, and those who consistently and selflessly perform acts of kindness”.

    In September 2017, the school announced the creation of an artificial intelligence research lab called the MIT-IBM Watson AI Lab. IBM will spend $240 million over the next decade, and the lab will be staffed by MIT and IBM scientists. In October 2018 MIT announced that it would open a new Schwarzman College of Computing dedicated to the study of artificial intelligence, named after lead donor and The Blackstone Group CEO Stephen Schwarzman. The focus of the new college is to study not just AI, but interdisciplinary AI education, and how AI can be used in fields as diverse as history and biology. The cost of buildings and new faculty for the new college is expected to be $1 billion upon completion.

    The Caltech/MIT Advanced aLIGO (US) was designed and constructed by a team of scientists from California Institute of Technology (US), Massachusetts Institute of Technology (US), and industrial contractors, and funded by the National Science Foundation (US) .

    Caltech /MIT Advanced aLigo

    It was designed to open the field of gravitational-wave astronomy through the detection of gravitational waves predicted by general relativity. Gravitational waves were detected for the first time by the LIGO detector in 2015. For contributions to the LIGO detector and the observation of gravitational waves, two Caltech physicists, Kip Thorne and Barry Barish, and Massachusetts Institute of Technology (US) physicist Rainer Weiss won the Nobel Prize in physics in 2017. Weiss, who is also an Massachusetts Institute of Technology (US) graduate, designed the laser interferometric technique, which served as the essential blueprint for the LIGO.

    The mission of Massachusetts Institute of Technology (US) is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of The Massachusetts Institute of Technology community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

  • richardmitnick 5:59 pm on January 24, 2022 Permalink | Reply
    Tags: "Complex" numbers, "Complex" numbers are widely exploited in classical and relativistic physics., "Physics(US)", "Quantum Mechanics Must Be Complex", A basic starting point for quantum theory is to represent a particle state by a vector in a "complex"-valued space called a Hilbert space., , Early on the pioneers of quantum mechanics abandoned the attempt to develop a quantum theory based on real numbers because they thought it impractical., Polarization-entangled photons generated by parametric down-conversion and detected in superconducting nanowire single-photon detectors., Quantum entanglement, , , Recent theoretical results suggested that a real-valued quantum theory could describe an unexpectedly broad range of quantum systems., Superconducting quantum processors in which the qubits have individual control and readout., The lack of a general proof left open some paths for refuting the equivalence between “complex” and “real” quantum theories., The possibility of using real numbers was never formally ruled out., This real-number approach has now been squashed by two independent experiments., Two teams show that within a standard formulation of quantum mechanics "complex" numbers are indispensable for describing experiments carried out on simple quantum networks.   

    From Physics(US): “Quantum Mechanics Must Be Complex” 

    About Physics

    From Physics(US)

    January 24, 2022

    Alessio Avella, The National Institute of Metrological Research [Istituto Nazionale di Ricerca Metrologica](IT)

    Two independent studies demonstrate that a formulation of quantum mechanics involving “complex” rather than real numbers is necessary to reproduce experimental results.

    Credit: Carin Cain/American Physical Society(US)
    Figure 1: Conceptual sketch of the three-party game used by [Chen and colleagues] and [Li and colleagues] to demonstrate that a real quantum theory cannot describe certain measurements on small quantum networks. The game involves two sources distributing entangled qubits to three observers, who calculate a “score” from measurements performed on the qubits. In both experiments, the obtained score isn’t compatible with a real-valued, traditional formulation of quantum mechanics.

    “Complex” numbers are widely exploited in classical and relativistic physics. In electromagnetism, for instance, they tremendously simplify the description of wave-like phenomena. However, in these physical theories, “complex” numbers aren’t strictly needed, as all meaningful observables can be expressed in terms of real numbers. Thus, “complex” analysis is just a powerful computational tool. But are “complex” numbers essential in quantum physics—where the mathematics (the Schrödinger equation, the Hilbert space, etc.) is intrinsically “complex”-valued? This simple question has accompanied the development of quantum mechanics since its origins, when Schrödinger, Lorentz, and Planck debated it in their correspondence [1]. But early on, the pioneers of quantum mechanics abandoned the attempt to develop a quantum theory based on real numbers because they thought it impractical. However, the possibility of using real numbers was never formally ruled out, and recent theoretical results suggested that a real-valued quantum theory could describe an unexpectedly broad range of quantum systems [2]. But this real-number approach has now been squashed by two independent experiments, performed by Ming-Cheng Chen of The University of Science and Technology [中国科学技术大学](CN) at Chinese Academy of Sciences [中国科学院](CN) [3] and by Zheng-Da Li of The Southern University of Science and Technology[南方科技大學](CN) [4]. The two teams show that within a standard formulation of quantum mechanics “complex” numbers are indispensable for describing experiments carried out on simple quantum networks.

    A basic starting point for quantum theory is to represent a particle state by a vector in a “complex”-valued space called a Hilbert space. However, for a single, isolated quantum system, finding a description based purely on real numbers is straightforward: It can simply be obtained by doubling the dimension of the Hilbert space, as the space of complex numbers is equivalent, or “isomorphic,” to a two-dimensional, real plane, with the two dimensions representing the real and imaginary part of “complex” numbers, respectively. The problem becomes less trivial when we consider the unique quantum correlations, such as entanglement, that arise in quantum mechanics. These correlations can violate the principle of local realism, as proven by so-called Bell inequality tests [5]. Violations of Bell tests may appear to require “complex” values for their description [6]. But in 2009, a theoretical work demonstrated that, using real numbers, it is possible to reproduce the statistics of any standard Bell experiment, even those involving multiple quantum systems [2]. The result reinforced the conjecture that “complex” numbers aren’t necessary, but the lack of a general proof left open some paths for refuting the equivalence between “complex” and “real” quantum theories.

    One such path was identified in 2021 through the brilliant theoretical work of Marc-Olivier Renou of the The Institute of Photonic Sciences [Instituto de Ciencias Fotónicas](ES)and co-workers [7]. The researchers considered two theories that are both based on the postulates of quantum mechanics, but one uses a “complex” Hilbert space, as in the traditional formulation, while the other uses a real space. They then devised Bell-like experiments that could prove the inadequacy of the real theory. In their theorized experiments, two independent sources distribute entangled qubits in a quantum network configuration, while causally independent measurements on the nodes can reveal quantum correlations that do not admit any real quantum representation.

    Chen and colleagues and Li and colleagues now provide the experimental demonstration of Renou and co-workers’ proposal in two different physical platforms. The experiments are conceptually based on a “game” in which three parties (Alice, Bob, and Charlie) perform a Bell-like experiment (Fig. 1). In this game, two sources distribute entangled qubits between Alice and Bob and between Bob and Charlie, respectively. Each party independently chooses, from a set of possibilities, the measurements to perform on their qubit(s). Since the sources are independent, the qubits sent to Alice and Charlie are originally uncorrelated. Bob receives a qubit from both sources and, by performing a Bell-state measurement, he generates entanglement between Alice’s and Charlie’s qubits even though these qubits never interacted (a procedure called “entanglement swapping” [8]). Finally, a “score” is calculated from the statistical distribution of measurement outcomes. As demonstrated by Renou and co-workers, a “complex” quantum theory can produce a larger score than the one produced by a real quantum theory.

    The two groups follow different approaches to implement the quantum game. Chen and colleagues use a superconducting quantum processor in which the qubits have individual control and readout. The main challenge of this approach is making the qubits, which sit on the same circuit, truly independent and decoupled—a stringent requirement for the Bell-like tests. Li and colleagues instead choose a photonic implementation that more easily achieves this independence. Specifically, they use polarization-entangled photons generated by parametric down-conversion and detected in superconducting nanowire single-photon detectors. The optical implementation comes, however, with a different challenge: The protocol proposed by Renou and co-workers requires a complete Bell-state measurement, which can be directly implemented using superconducting qubits but is not achievable exploiting linear optical phenomena. Therefore, Li and colleagues had to rely on a so-called “partial” Bell-state measurement.

    Despite the difficulties inherent in each implementation, both experiments deliver compelling results. Impressively, they beat the score of real theory by many standard deviations (by 43 σ and 4.5 σ for Chen’s and Li’s experiments, respectively), providing convincing proof that complex numbers are needed to describe the experiments.

    Interestingly, both experiments are based on a minimal quantum network scheme (two sources and three nodes), which is a promising building block for a future quantum internet. The results thus offer one more demonstration that the availability of new quantum technologies is closely linked to the possibility of testing foundational aspects of quantum mechanics. Conversely, these new fundamental insights on quantum mechanics could have unexpected implications on the development of new quantum information technologies.

    We must be careful, however, in assessing the implications of these results. One might be tempted to conclude that “complex” numbers are indispensable to describe the physical reality of the Universe. However, this conclusion is true only if we accept the standard framework of quantum mechanics, which is based on several postulates. As Renou and his co-workers point out, these results would not be applicable to alternative formulations of quantum mechanics, such as Bohmian mechanics, which are based on different postulates. Therefore, these results could stimulate attempts to go beyond the standard formalism of quantum mechanics, which, despite great successes in predicting experimental results, is often considered inadequate from an interpretative point of view [9].


    C. N. Yang, “Square root of minus one, complex phases and Erwin Schrödinger,” Selected Papers II with Commentary (World Scientific, Hackensack, 2013)[Amazon][WorldCat].
    M. McKague et al., “Simulating quantum systems using real Hilbert spaces,” Phys. Rev. Lett. 102, 020505 (2009).
    M.-C. Chen et al., “Ruling out real-valued standard formalism of quantum theory,” Phys. Rev. Lett. 128, 040403 (2022).
    Z.-D. Li et al., “Testing real quantum theory in an optical quantum network,” Phys. Rev. Lett. 128, 040402 (2022).
    A. Aspect, “Closing the door on Einstein and Bohr’s quantum debate,” Physics 8, 123 (2015).
    N. Gisin, “Bell Inequalities: Many Questions, a Few Answers,” in Quantum Reality, Relativistic Causality, and Closing the Epistemic Circle, edited by W. C. Myrvold et al. The Western Ontario Series in Philosophy of Science, Vol. 73 (Springer, Dordrecht, 2009)[Amazon][WorldCat].
    M.-O. Renou et al., “Quantum theory based on real numbers can be experimentally falsified,” Nature 600, 625 (2021).
    J.-W. Pan et al., “Experimental entanglement swapping: Entangling photons that never interacted,” Phys. Rev. Lett. 80, 3891 (1998).
    T. Norsen, Foundations of Quantum Mechanics – An Exploration of the Physical Meaning of Quantum Theory, Undergraduate Lecture Notes in Physics (Springer, Cham, 2017)[Amazon][WorldCat].

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Physicists are drowning in a flood of research papers in their own fields and coping with an even larger deluge in other areas of physics. How can an active researcher stay informed about the most important developments in physics? Physics (US) highlights a selection of papers from the Physical Review journals. In consultation with expert scientists, the editors choose these papers for their importance and/or intrinsic interest. To highlight these papers, Physics features three kinds of articles: Viewpoints are commentaries written by active researchers, who are asked to explain the results to physicists in other subfields. Focus stories are written by professional science writers in a journalistic style and are intended to be accessible to students and non-experts. Synopses are brief editor-written summaries. Physics provides a much-needed guide to the best in physics, and we welcome your comments.

  • richardmitnick 11:15 am on January 18, 2022 Permalink | Reply
    Tags: "What is quantum information?", A classical bit is definitely a 0 or a 1 but a quantum bit- called a qubit- can be a bit of both., , , Classical information follows a set of rules. Quantum information breaks those rules., Classical information is discrete: A bit is always either a 0 or a 1 and nothing in between., In a classical computer information travels in the form of a string of bits-a pattern of 1s and 0s., Quantum entanglement, Quantum information allows a qubit to carry a different kind of information: continuous information about the relative balance of 0 and 1 within the qubit., Quantum information breaks the rules of classical information in a way that could allow us to answer questions that a classical computer cannot., Quantum information has to be carefully protected from its environment lest it become entangled with that environment and effectively lost., Quantum information is not discrete. A classical bit is definitely a 0 or a 1, , , The way we process and interact with quantum information is fundamentally different.   

    From Symmetry: “What is quantum information?” 

    Symmetry Mag

    From Symmetry

    Nathan Collins

    Illustration by Sandbox Studio, Chicago with Ana Kova.

    Quantum information breaks the rules of classical information in a way that could allow us to answer questions that a classical computer cannot.

    Imagine mailing a letter. You, as the person sending the letter, know what the letter says. But the situation is different for the person you’re mailing the letter to. Until they read it, they generally won’t know what it says.

    This is the way scientists think about information, at least in the classical sense.

    A computer stores information, sends and receives information, and processes information. In a classical computer, the information travels in the form of a string of bits—a pattern of 1s and 0s. As each bit arrives, the recipient doesn’t know what value it will have; from their point of view, it is just as likely to be a 0 as it is to be a 1. To be sure, it will definitely be one or the other, but which it is will be revealed only once it arrives.

    In this sense, upon its arrival each bit resolves a certain amount of uncertainty.

    Now, it could be that knowing the start of a message gives clues about the rest of it. If a message starts, “O Romeo, Romeo,” it’s a good bet the message will conclude, “wherefore art thou Romeo?”

    Still, knowing the first part of the message does not determine—perhaps more to the point, it does not affect—the next part of the message. It could be that the rest of the message is “could you get me a sandwich?”

    All of this makes sense because classical information follows a set of rules.

    Quantum information breaks those rules, making it at once a powerful basis for computing and an exquisitely fragile beast.

    The quantum difference

    The rules of classical information are so intuitive that they are easy to take for granted.

    First, classical information is discrete: A bit is always either a 0 or a 1 and nothing in between. Second, bits are deterministic. That is, to the extent there is uncertainty in a bit, that uncertainty exists in the mind of someone who has not yet received a message (or in the possibility that an error might change the value of the bit). Finally, classical information is local—as in the Shakespeare example, a bit may suggest what’s coming, but observing that bit doesn’t actually affect any other bits.

    Quantum information, on the other hand, is not discrete. A classical bit is definitely a 0 or a 1, but a quantum bit, called a qubit, can be a bit of both.

    This feature allows a qubit to carry a different kind of information: continuous information about the relative balance of 0 and 1 within the qubit. Quantum algorithms can sometimes use this fact to run more efficiently than their classical counterparts.

    Quantum information is also not deterministic. When someone takes a look at a classical bit, it simply is a 0 or a 1, as it was beforehand and as it will be afterward, apart from the possibility of error. Not so with qubits, which are affected by the measurement.

    Although the qubit can be in any mix of 0 and 1, measuring it—as one would need to do to read the output of a calculation—forces it to be either 0 or 1. In general, there is some chance the answer will come out 0 and some complementary chance it will come out 1. This is not an error, and it is not the same as a message recipient simply not yet knowing the bit’s value—it is a fundamental feature of quantum physics.

    Importantly, this feature also means that reading the output of a quantum computer—a kind of measurement—destroys most of the information it stores. Where once there was a superposition, measurement makes it so that all that’s left is a 0 or a 1.

    Finally, quantum information is not local. While each classical bit is independent of every other bit, a qubit is typically not independent of other qubits.

    For instance, engineers can prepare a pair of qubits in a state such that if we measured one qubit as a 0, the other would have to be a 1, and vice versa. In theory, engineers can build up systems with as many qubits as they want, where each qubit’s state depends on many other qubits’ states, and all are part of a complex entangled system.

    This observation has a curious consequence: Where classical bits store information locally and independently of each other, quantum information is typically stored in the relationships between individual qubits.

    The upside of quantum information

    Quantum superposition, measurement and entanglement introduce certain difficulties. For instance, there are more ways for errors to creep into the system. And quantum information has to be carefully protected from its environment, lest it become entangled with that environment and effectively lost. Quantum error correction is in turn more challenging, since a problem that affects one qubit can end up corrupting the entire system.

    But quantum information brings with it some remarkable advantages as well, and these advantages are big enough to make it worth solving the challenges that arise.

    One early argument for quantum computing goes something like this: Classical computers are deterministic things—that is, when they perform a calculation, they produce only one answer. Nature, on the other hand, is not perfectly predictable. Since some aspects of it are fundamentally quantum mechanical, nature can produce more than one answer. That means a classical computer is going to have a hard time simulating quantum behavior.

    Imagine using a classical computer to simulate a single qubit. At a bare minimum, a classical computer would need many bits to describe what state the qubit was in, since the qubit could be in any combination of the 0 and 1 states. A classical computer would need still more bits to encode how qubits are entangled with each other, and even more to simulate what happens when someone performs a quantum algorithm and measures the output.

    In other words, it takes a lot more than 10 classical bits to simulate 10 quantum bits, suggesting that one might be able to do a lot more with 10 quantum bits than one could with 10 classical bits.

    But even that thought experiment doesn’t fully capture the distinction. There isn’t simply more information in a quantum bit—quantum superposition, measurement and entanglement also mean that the way we process and interact with quantum information is fundamentally different.

    One consequence is that quantum computers could be better than classical computers even when it comes to solving some deterministic problems. A now-classic example is factoring, or finding the prime numbers that multiply together to make another number. While there is only one way to factor any number, factoring large numbers is a very hard problem on classical computers. On a quantum computer, it’s relatively easy.

    These distinctions don’t mean that quantum computers are better than classical computers at everything. The main point is that they are different and therefore suited to solving different kinds of problems, and indeed researchers are working hard to understand which computational problems quantum computers would be best suited to. What’s clear is that quantum information opens up new possibilities, and the future is still unwritten.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Symmetry is a joint Fermilab/SLAC publication.

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