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  • richardmitnick 9:38 pm on May 10, 2018 Permalink | Reply
    Tags: "Primed for a quantum leap in research", , U Chicago   

    From University of Chicago: “Primed for a quantum leap in research” 

    U Chicago bloc

    From University of Chicago

    5.10.18
    Louise Lerner

    UChicago scientists and engineers at forefront of technology revolution.

    1
    Photo courtesy of Kevin Satzinger

    Since being proposed a half-century ago, quantum computing has been confined to science fiction and the daydreams of physicists.

    Then that all changed.

    “In the last decade, the field of quantum information science has rapidly expanded beyond fundamental research toward real-world applications,” said Prof. David Awschalom of the Institute for Molecular Engineering at the University of Chicago.

    Behind the scenes, a number of breakthroughs have made it possible for scientists to encode and manipulate information in quantum systems, which behave according to the strange laws of quantum mechanics. Today, university scientists like those at the IME are fleshing out the fundamental rules of controlling such systems, while Google, IBM, Microsoft and Intel are pouring millions of dollars in a race to build those concepts into working computers.


    Scientists at the University of Chicago’s Institute for Molecular Engineering are exploring a vast new field made possible by the ability to manipulate quantum systems.
    (Video by UChicago Creative)

    Quantum computers should be able to solve certain problems much faster than current computers. Because they naturally process multiple possibilities in parallel, it’s thought they could speed up searches for new pharmaceuticals, improve batteries and find greener ways to make chemicals. (They’re also of significant interest to governments because such computers might be able to factor the large numbers that currently encrypt the world’s financial, political and military secrets.)

    But computing isn’t the only way to tap quantum quirks. Scientists at UChicago are shaping a vast new field made possible by our growing ability to manipulate quantum systems. In fact, of the major quantum technologies, researchers see computers as the furthest out to achieve. Before then, there are possibilities for innately secure communication and precise navigation systems. Quantum sensors might find hidden underground oil pockets, improve earthquake monitoring, unravel the structure of single molecules or peek at the busy dance of proteins inside a cell.

    2
    A UChicago team accidentally discovered a new way of using light to draw and erase quantum circuits. (Artist’s rendition by Peter Allen)

    “The Institute for Molecular Engineering is looking 10 or 15 years down the line,” said Matthew Tirrell, the founding Pritzker Director and dean of the Institute for Molecular Engineering. “While Google and Intel are working to build prototype systems, we need to lay down a scientific foundation of understanding for these quantum technologies, and to do that, we are building an institute that brings together experts with deep knowledge in a variety of adjacent fields.”

    The right ingredients for discovery

    The IME is uniquely positioned to tackle the science from which quantum technologies will emerge. In addition to its state-of-the-art Pritzker Nanofabrication Facility, the institute works closely with UChicago’s two affiliated national laboratories, Argonne National Laboratory and Fermilab; in fact, last year, the IME formed a hub called the Chicago Quantum Exchange to coordinate research among the three institutions. The institute is also tied with UChicago’s Polsky Center for Entrepreneurship and Innovation to commercialize breakthroughs.

    The institute is set up to solve problems that span multiple scientific fields—encouraging researchers to leverage the wide range of expertise around them, which is key to quickly realizing the full potential of discoveries made in the lab.

    ___________________________________________________________

    “You need to lay down a scientific foundation of understanding for these quantum technologies, and to do that, you need a center that combines really deep knowledge in a variety of fields.”

    —Matt Tirrell, the founding Pritzker Director and dean of the Institute for Molecular Engineering

    “In the last decade, the field of quantum information science has rapidly expanded beyond fundamental research toward real-world applications.”

    —Prof. David Awschalom

    ___________________________________________________________

    For example: A few years ago, Awschalom’s research group discovered quantum behavior in a common material called silicon carbide. No one had expected to see it there; and no one could explain why it was happening. So they reached out to fellow researchers, including Giulia Galli, the Liew Family Professor of Electronic Structure and Simulations at the Institute for Molecular Engineering.

    “We met with Giulia, who is a theoretical physicist. Within a few months, she and her students came up with some clever modeling to explain the underlying behavior we observed,” Awschalom said. “Now we are collaborating with Andrew Cleland next door to start incorporating these quantum states into hybrid devices. There are now hundreds of potential ways to develop these materials into useful systems.”

    The result of all this is research that can more quickly spin up to become part of our lives. “Ultimately, we think quantum technologies will impact the world in many ways beyond computing,” said Awschalom.

    3
    Asst. Prof. Jonathan Simon makes “quantum Legos” out of photons to explore principles of quantum systems. (Photo by Jean Lachat)

    Leave your intuition at the door

    Quantum mechanics is how scientists describe the behavior of fundamental particles. The theory was built over the 20th century, and some of its central tenets were proposed by Einstein, though he was famously uneasy about their implications. Physicists originally began to test these theories by observing the behavior of particles, such as photons of light, which act both as waves and as particles. Pull on that thread, and you discover a universe that does not square with the world as we’re used to.

    “It’s very hard to develop a good intuition for quantum behavior,” Awschalom said, “because everything behaves so differently from the classical world we know.”

    According to quantum mechanics, objects can occupy different locations at the same time; they can go through walls; and they can be entangled with one another, acting as though they “know” what’s happening miles or even light-years away. And if you measure a quantum state, it can change. So scientists have to build systems that create, manipulate and move these particles, while studiously avoiding interacting with them more than strictly necessary.

    The property that sparked the idea for quantum computers is that particles can exist in two positions at the same time, a concept called “superposition.” You might be familiar with the binary language that underwrites all of today’s computers, which contains just two options: 0 and 1. A quantum computer could expand that language by encoding information that exists in more than one state at a time, which lets you attack questions very differently. Since nature behaves quantum-mechanically, at a certain point, we need a quantum computer to simulate those processes. Along with completely new computers comes a need for new algorithms: across the street from the IME, a $10 million NSF project headed by Fred Chong, the Seymour Goodman Professor in the Department of Computer Science, will design hardware and software to help realize the potential of quantum computing more rapidly.

    4
    IME scientists invented a configuration that can flip the state of a quantum bit, from ‘off’ to ‘on,’ 300 percent faster than conventional methods. (Artist’s rendition by Peter Allen)

    There are already some small systems of about five quantum bits (called qubits) that anyone can play with online. Within the year, some of the largest tech companies are expected to unveil working systems with 50 or more qubits.

    “Every time you add a qubit, you double the computer’s power, which gets you enormous power very quickly,” said Andrew Cleland, the John A. MacLean Sr. Professor for Molecular Engineering Innovation and Enterprise. “But it’s very hard to keep them all behaving the way you want.”

    The difficult bit

    Quantum systems are extremely sensitive. They get thrown out of alignment by the tiniest changes in temperature or magnetism, noise or someone walking by. “A major challenge in this field is to preserve the integrity of quantum signals in real-world devices,” Awschalom said.

    “Our really good systems now last for tens of microseconds,” said Asst. Prof. David Schuster. “But you can do a lot in that time.”

    5
    A quantum device known as the “0-Pi” circuit, the first of a new class of protected superconducting qubits being developed at the University of Chicago in the lab of Prof. David Schuster. (Courtesy of Nate Earnest and Abigail Shearrow)

    But quantum’s quirks are what make it interesting. While not being able to read your information without screwing everything up is frustrating, it makes it perfect for designing a hack-proof communication system: If someone eavesdrops, the information will be destroyed.

    Similarly, quantum systems’ tendency to respond to the least disturbances make them perfect sensors. “With quantum sensors, you are dealing with the absolute smallest amounts of energy, so you can sense things that other technologies cannot,” Cleland said.

    They could detect something as small as tiny shifts in gravity that indicate the ground is denser in one area than another—which could detect untapped pockets of oil or minerals or get us closer to predicting earthquakes. They could even potentially detect dark matter.

    Medicine is interested, too. Untangling the structure of proteins and cellular structures is central to making better pharmaceuticals, and it’s thought that quantum sensors could do this much faster and with better sensitivity. It could even one day peer inside the workings of our own cells. “Think of the possibilities for advancing biology and medicine if we can place nano-scale quantum sensors into living cells and observe their behavior in real time,” Awschalom said.

    Yet the applications will only come once scientists understand the underlying principles of how to properly control quantum systems. First they need to understand how to prevent magnetic fields from knocking such systems out quickly; how to make bigger systems hold together; and how to interface them with existing technology.

    “These are important questions for university scientists and engineers, because this underlying physics will ultimately determine the limits of quantum technologies,” Awschalom said. “To answer these questions, we need groups of computer scientists, engineers and physicists working together.”

    And as that science grows into full-fledged technology, the world will need a new generation of quantum engineers, Awschalom said. Another $1.5 million from NSF will fund an innovative program, headed by Awschalom and Harvard’s Evelyn Hu, that pairs graduate students to tackle specific problems along with mentors from both academia and industry.

    The field is exciting to work in, IME researchers said, especially for scientists who’ve seen the field evolving before their eyes. “When I was in grad school, this was all pretty pictures in textbooks, that you knew you couldn’t apply to anything in the real world,” Cleland said. “But the barriers started falling away, and now we’re not only actually doing those textbook examples, but going well beyond them.”

    See the full article here .

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    U Chicago Campus

    An intellectual destination

    One of the world’s premier academic and research institutions, the University of Chicago has driven new ways of thinking since our 1890 founding. Today, UChicago is an intellectual destination that draws inspired scholars to our Hyde Park and international campuses, keeping UChicago at the nexus of ideas that challenge and change the world.

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  • richardmitnick 2:59 pm on April 10, 2018 Permalink | Reply
    Tags: Computation Institute, U Chicago, UChicago Department of Computer Science, UChicago launches center for data science and computing research   

    From University of Chicago: “UChicago launches center for data science and computing research” 

    U Chicago bloc

    University of Chicago

    April 6, 2018
    Rob Mitchum

    1
    The new Center for Data and Applied Computing will be located in the renovated John Crerar Library. Illustration by Jennifer Fifield.

    The University of Chicago is launching the Center for Data and Applied Computing, a research center for developing new methods in computation and data analytics and applying them to ambitious projects across the full spectrum of science and scholarship.

    The Center for Data and Applied Computing, which opens this summer, will provide computationally focused, interdisciplinary projects at UChicago with resources, space and a network for collaboration on campus and around the world. The center will award seed funding to a select group of projects, house and provide administrative support to core projects with external funding, and organize workshops, talks and other gatherings that generate fresh ideas from UChicago faculty, researchers and students.

    “Building capacity for computation-based projects is essential to advance research, education and the impact of scholarly work in a wide range of fields,” said President Robert J. Zimmer. “Collaborative efforts using data science, artificial intelligence and other computing approaches are rapidly creating dramatic new opportunities for academic work as well as new entrepreneurial opportunities. The center will support and encourage transformative activities with these tools.”

    The center will work closely with the expanding UChicago Department of Computer Science, while sitting between departments and divisions, incubating data and compute-intensive applied research initiatives that cut across traditional boundaries. The center will be led by a faculty director and be located in the renovated John Crerar Library, which is scheduled to reopen in the fall.

    The new center builds on the successes of the Computation Institute, which will close later this year. The institute’s legacy is one of forward-looking projects, which built and managed technologies that enable global sharing of scientific data, applied high-performance computing to studies of the universe, genetics and climate change, and developed novel, data-driven tools for studying cities, public policy and the humanities. The institute was founded in 1999 to foster collaborative and applied computational research.

    “Over the last two decades, data and computing have transformed research, from traditionally data-intensive fields such as physics and astronomy to new territories such as the humanities and social sciences,” said Michael Franklin, the Liew Family Chair of Computer Science and senior adviser to the Provost on computation and data science. “The Computation Institute was essential in positioning the University of Chicago at the crest of this wave, creating new technologies and multidisciplinary strategies that accelerated discovery both here and around the world.”

    Upon its launch, the Center for Data and Applied Computing will host continuing research collaborations from the Computation Institute and other areas of campus. The inaugural group of projects will be selected by its faculty director and a steering committee made up of faculty members from across campus. The center also will provide opportunities for researchers from UChicago-affiliated laboratories such as Argonne National Laboratory, Fermilab and the Marine Biological Laboratory to participate in data science and computing collaborations with UChicago faculty.

    “As we expand computer and data science at the University, the center will be the primary interface for building new partnerships and projects that span departments and enable important discoveries,” Franklin said. “The center will help define the future of these cutting-edge approaches across the breadth of intellectual domains on campus.”

    See the full article here .

    Please help promote STEM in your local schools.

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    An intellectual destination

    One of the world’s premier academic and research institutions, the University of Chicago has driven new ways of thinking since our 1890 founding. Today, UChicago is an intellectual destination that draws inspired scholars to our Hyde Park and international campuses, keeping UChicago at the nexus of ideas that challenge and change the world.

     
  • richardmitnick 11:27 am on April 4, 2018 Permalink | Reply
    Tags: , , , , , Scientists confirm water trapped inside diamonds deep below Earth’s surface, U Chicago   

    From University of Chicago: “Scientists confirm water trapped inside diamonds deep below Earth’s surface” 

    U Chicago bloc

    University of Chicago

    March 30, 2018
    Karen Mellen

    1
    Researchers working at Argonne National Laboratory have identified a form of water trapped within diamonds that crystallized deep in the Earth’s mantle. (Pictured: Rough diamond in kimberlite.) Copyright Getty Images.

    Water occurs naturally as far as at least 250 miles below the Earth’s surface, according to a study published in Science last week by researchers from the University of Chicago and others. The discovery, which relies on extremely bright X-ray beams from the Advanced Photon Source at Argonne National Laboratory, could change our understanding of how water circulates deep in the Earth’s mantle and how heat escapes from the lower regions of our planet.


    ANL/APS

    The researchers identified a form of water known as Ice-VII, which was trapped within diamonds that crystallized deep in the Earth’s mantle. This is the first time Ice-VII has been discovered in a natural sample, making the compound a new mineral accepted by the International Mineralogical Association.

    The study is the latest in a long line of research projects at the Advanced Photon Source, a massive X-ray facility used by thousands of researchers every year, which have shed light on the composition and makeup of the deep Earth. Humans cannot explore these regions directly, so the Advanced Photon Source lets them use high-powered X-ray beams to analyze inclusions in diamonds formed in the deep Earth.

    2
    UChicago researchers involved in the work at Argonne’s Advanced Photon Source included (from left): Vitali Prakapenka, Tony Lanzirotti, Matt Newville, Eran Greenberg and Dongzhou Zhang. (Photo by Rick Fenner / Argonne National Laboratory).

    “We are interested in those inclusions because they tell us about the chemical composition and conditions in the deep Earth when the diamond was formed,” said Antonio Lanzirotti, a UChicago research associate professor and co-author on the study.

    In this case, researchers analyzed rough, uncut diamonds mined from regions in China and Africa. Using an optical microscope, mineralogists first identified inclusions, or impurities, which must have formed when the diamond crystallized. But to positively identify the composition of these inclusions, mineralogists needed a stronger instrument: the University of Chicago’s GeoSoilEnviroCARS’s beam lines at the Advanced Photon Source.

    Thanks to the very high brightness of the X-rays, which are a billion times more intense than typical X-ray machines, scientists can determine the molecular or atomic makeup of specimens that are only micrometers across. When the beam of X-rays hits the molecules of the specimen, they scatter into unique patterns that reveal their molecular makeup.

    What the team identified was surprising: water, in the form of ice.

    The composition of the water is the same as the water that we drink and use every day, but in a cubic crystalline form—the result of the extremely high pressure of the diamond.

    This form of water, Ice-VII, was created in the lab decades ago, but this study was the first to confirm that it also forms naturally. Because of the pressure required for diamonds to form, the scientists know that these specimens formed between 410 and 660 kilometers (250 to 410 miles) below the Earth’s surface.

    The researchers said the significance of the study is profound because it shows that flowing water is present much deeper below the Earth’s surface than originally thought. Going forward, the results raise a number of important questions about how water is recycled in the Earth and how heat is circulated. Oliver Tschauner, the lead author on the study and a mineralogist at University of Nevada in Las Vegas, said the discovery can help scientists create new, more accurate models of what’s going on inside the Earth, specifically how and where heat is generated under the Earth’s crust. This may help scientists better understand one of the driving mechanisms for plate tectonics.

    ___________________________________________________________
    “[T]hanks to the amazing technical capabilities of the Advanced Photon Source, this team of researchers was able to pinpoint and study the exact area on the diamonds that trapped the water”
    Stephen Streiffer, associate laboratory director for photon sciences
    ___________________________________________________________

    “This wasn’t easy to find,” said Vitali Prakapenka, a UChicago research professor and a co-author of the study. “People have been searching for this kind of inclusion for a long time.”

    For now, the team is wondering whether the mineral Ice-VII will be renamed, now that it is officially a mineral. This is not the first mineral to be identified thanks to research done at the Advanced Photon Source GSECARS beamlines: Bridgmanite, the Earth’s most abundant mineral and a high-density form of magnesium iron silicate, was researched extensively there before it was named. Tschauner was a lead author on that study, too.

    “In this study, thanks to the amazing technical capabilities of the Advanced Photon Source, this team of researchers was able to pinpoint and study the exact area on the diamonds that trapped the water,” said Stephen Streiffer, Argonne associate laboratory director for photon sciences and director of the Advanced Photon Source. “That area was just a few microns wide. To put that in context, a human hair is about 75 microns wide.

    “This research, enabled by partners from the University of Chicago and the University of Nevada, Las Vegas, among other institutions, is just the latest example of how the APS is a vital tool for researchers across scientific disciplines,” he said.

    Other GSECARS co-authors are Eran Greenberg, Dongzhou Zhang and Matt Newville.

    In addition to the University of Chicago and UNLV, other institutions cited in the study include the California Institute of Technology, China University of Geosciences, the University of Hawaii at Manoa and the Royal Ontario Museum, Toronto. Data also was collected at Carnegie Institute of Washington’s High Pressure Collaborative Access Team at the Advanced Photon Source and the Advanced Light Source at Lawrence Berkeley National Lab.

    LBNL/ALS

    LBNL Advanced Light Source storage ring

    See the full article here .

    Please help promote STEM in your local schools.

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    U Chicago Campus

    An intellectual destination

    One of the world’s premier academic and research institutions, the University of Chicago has driven new ways of thinking since our 1890 founding. Today, UChicago is an intellectual destination that draws inspired scholars to our Hyde Park and international campuses, keeping UChicago at the nexus of ideas that challenge and change the world.

     
  • richardmitnick 2:49 pm on March 27, 2018 Permalink | Reply
    Tags: , , , , , Quantum systems, U Chicago   

    From University of Chicago: “UChicago scientists build trap to make tiny packages of light ‘collide’” 

    U Chicago bloc

    University of Chicago

    March 27, 2018
    Louise Lerner

    Study examines how to manipulate photons for quantum engineering.

    1
    Asst. Prof. Jonathan Simon with the photon collider—the blue light is reflected by a precisely arranged set of mirrors to manipulate individual photons so that they ‘collide’ with one another. Photo by Jean Lachat.

    The universe is illuminated via photons, the tiny individual particles that make up light, but they don’t interact with each other. To make them see the light, a team of University of Chicago physicists built a trap to help photons bounce off each other.

    Their photon collider, described in the March 19 edition of Nature Physics, is the latest effort to make photons behave like other particles such as electrons—a step toward greater understanding and control of quantum systems, which may one day manifest as technology with new properties.

    Quantum systems behave according to the strange laws that govern the smallest particles in the universe, like electrons. Scientists are increasingly interested in exploring new ways to harness the particles’ odd behaviors, like being in two states at once, and then choosing one only when measured.

    Jonathan Simon, the Neubauer Family Assistant Professor of Physics and the James Franck Institute, is interested in how walls dividing matter and light begin to break down at this scale. Most electronic systems use electrons as the moving parts, but photons can display quantum properties just as easily as electrons—and photons’ quirks could both offer advantages as technologies and serve as models to understand the more slippery electrons. So his team wants to manipulate and stack photons to build matter out of light.

    3
    (From left): Asst. Prof. Jonathan Simon, graduate student Ningyuan Jia and postdoctoral scholar Logan Clark with the photon collider. (Photo by Jean Lachat).

    “Essentially we want to make photon systems into a kind of quantum Legos—blown-up materials that you can more easily study and tease out basic quantum design principles,” said Simon, who is also a fellow of the Institute for Molecular Engineering.

    But because photons have no mass, no charge and no chill—they always want to travel at the speed of light—making them behave like other particles takes some delicate finagling.

    Two years ago, Simon’s lab figured out a way to make photons behave as though they were in a magnetic field. The next challenge was to make photons react to each others’ presence, which light normally doesn’t.

    In their lab, the scientists shine a weak laser to send a photon into a trap: a series of mirrors that keep it continuously bouncing around inside. The photon interacts with a cloud of rubidium atoms that are prepared so that once any atom in the cloud absorbs a photon, no other atom can. This repels other incoming photons behind them—as though they were “colliding.”

    This offers a new way to understand some of the more poorly understood quantum properties, like entanglement—the state in which two particles become linked and share the same state even at great distances.

    4
    Scientists use a weak laser to send a photon into a series of mirrors, which keeps the photon continuously bouncing around inside. (Photo by Jean Lachat).

    “We don’t have much intuition about what kinds of entanglement lead to which properties,” Simon said, “so if we can understand an analogous system, that could give us some insight.”

    There’s also interest in using photon systems for ultra-secure communications and to make computers. The team’s next step, Simon said, is to combine this setup with their previous one, to produce a set of photons that both interact with each other and with magnetic fields.

    The first author on the study was UChicago graduate student Ningyuan Jia. Other co-authors were graduate students Albert Ryou (now at the University of Washington), Nathan Schine and Alexandros Georgakopoulos, as well as postdoctoral scholars Ariel Sommer (now at Lehigh University) and Logan Clark.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

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    U Chicago Campus

    An intellectual destination

    One of the world’s premier academic and research institutions, the University of Chicago has driven new ways of thinking since our 1890 founding. Today, UChicago is an intellectual destination that draws inspired scholars to our Hyde Park and international campuses, keeping UChicago at the nexus of ideas that challenge and change the world.

     
  • richardmitnick 8:52 am on March 1, 2018 Permalink | Reply
    Tags: , , U Chicago   

    From University of Chicago: “UChicago scientists to lead $10 million NSF ‘expedition’ for practical quantum computing” 

    U Chicago bloc

    University of Chicago

    February 27, 2018
    Rob Mitchum

    1
    A multimode resonator used to store large numbers of qubits, the fundamental component of a quantum computer. Photo by Nate Earnest/David Schuster Laboratory

    2
    To operate, quantum computers require temperatures near absolute zero, conditions created by a dilution refrigerator. Photo by Nate Earnest/David Schuster Laboratory.

    University of Chicago computer scientists will lead a $10 million “expedition” into the burgeoning field of quantum computing, bringing applications of the nascent technology for computer science, physics, chemistry and other fields at least a decade closer to practical use.

    Quantum computers harness the unique properties of quantum physics in machines that scientists hope will eventually perform complex calculations that are prohibitively slow or even impossible for today’s computers. In recent months, companies such as IBM, Intel and Google have unveiled new quantum computing prototypes approaching 50 quantum bits—or “qubits”—a new milestone in the race for machines capable of producing unprecedented discoveries.

    Yet despite these advances, there remains a wide gap between the quantum designs currently in use and the algorithms necessary to make full use of their power. The new, multi-institutional Enabling Practical-Scale Quantum Computing project, funded by the National Science Foundation’s Expeditions in Computing program, will bridge this gap through the co-design of hardware and software that helps scientists realize the potential of quantum computing more rapidly. Expeditions are the largest single-project investments made by the NSF and represent the most visionary and high-impact research in computer science.

    “We want to close the gap enough that we can do something promising with these machines,” said Fred Chong, the Seymour Goodman Professor in the Department of Computer Science at the University of Chicago and lead investigator on the project. “What we aim to do is to make quantum algorithms and machines meet, in a useful way, 10 or more years earlier than they would otherwise—five years from now instead of 15 years from now.”

    Uniting experts in algorithms, software, computer architecture and education from UChicago, MIT, Princeton, Georgia Tech and the University of California, Santa Barbara, EPiQC will develop these elements in tandem to take full advantage of new quantum machines. The collaboration will also establish a community of academic and industry partners and create new educational programs for students from elementary school to graduate school, training the next generation of quantum computer scientists.

    “Without a coordinated effort such as EPiQC, what’s going to happen is these computers will come out and no one will be able to program them, and they’ll need a much larger machine in order to do the computation that they want to do,” said Diana Franklin, director of computer science education at UChicago STEM Education and a research associate professor at UChicago. “It makes it so that practical quantum computers can be released so much earlier than they would be otherwise.”

    Missing pieces in quantum computing

    The promise of quantum computing lies in the ability of qubits to occupy a “superposition” of states, rather than the binary 1 or 0 of classical computing bits. Due to this difference, each additional qubit doubles the computing power of a machine, producing exponential gains that could eventually push quantum computers past the capabilities of today’s largest supercomputers. Scientists could then use these machines to run simulations and solve equations too complex for classical computers, leading to new discoveries in drug and material design, agriculture, cryptography and transportation optimization.

    However, many of the algorithms designed thus far to exploit these quantum advantages require the use of much more powerful machines than will be available in the near future. Scientists also lack the software needed to adapt these algorithms for practical use on actual machines, as well as the infrastructure tools necessary for programming these new technologies.

    “The big missing piece in quantum computing is what can we do with it that’s useful,” Chong said. “We want to think about it in very practical terms. What happens when you have a small number of devices, you can only run them for a short amount of time, and you have noise and errors—will the algorithms work then, and how can we change them to make them work better? And how can we change the machine to make the algorithms work better?”

    The project’s education and outreach efforts will focus on exposing students of all ages to quantum concepts and principles, preparing them for the new approaches needed to program and use quantum computers. The collaboration also will engage partners from industry and other universities to form a consortium that can share research ideas and new tools as they are developed.

    “EPiQC will play an essential role in researching efficient co-design of algorithms, software and devices, as well as creating tools to put quantum in front of a wider audience for even greater quantum programming creativity, and eventual breakthrough quantum applications,” said Jay Gambetta, manager of quantum information and computation at IBM Research. “EPiQC will also develop curricula to help train a much-needed workforce to drive quantum computing forward.”

    The EPiQC project will leverage substantial investments by the University of Chicago in computer science, including a major faculty hiring initiative and new facilities for computer and data science. The project also will coordinate with UChicago STEM Education and the Chicago Quantum Exchange, a partnership of UChicago, Argonne National Laboratory and Fermi National Laboratory for advancing academic and industrial efforts in the science and engineering of quantum information. Additional UChicago faculty on the project include John Reppy, professor in the Department of Computer Science; and David Schuster, assistant professor in the Department of Physics.

    “Part of what we want to do is not only produce tools and educate people and help the community grow, but also help people appreciate that there are some really important problems to be solved here, and inspire people to work on them,” Chong said. “It’s really one of our core missions to build a research community with enough critical mass to spur innovation and realize the potential of this incredibly promising computing technology.”

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    U Chicago Campus

    An intellectual destination

    One of the world’s premier academic and research institutions, the University of Chicago has driven new ways of thinking since our 1890 founding. Today, UChicago is an intellectual destination that draws inspired scholars to our Hyde Park and international campuses, keeping UChicago at the nexus of ideas that challenge and change the world.

     
  • richardmitnick 2:02 pm on February 9, 2018 Permalink | Reply
    Tags: ANL MIRA supercomputer, , Astrophysicists settle century-old cosmic debate on magnetism of planets and stars, , , , OMEGA Laser Facility in Rochester N.Y, U Chicago   

    From University of Chicago: “Astrophysicists settle century-old cosmic debate on magnetism of planets and stars” 

    U Chicago bloc

    University of Chicago

    February 9, 2018
    Rob Mitchum

    Laser experiments verify ‘turbulent dynamo’ theory of how cosmic magnetic fields are created

    1
    Three-dimensional FLASH simulation of the experimental platform, performed on the Mira supercomputer. Shown are renderings of the simulated magnetic fields before the flows collide. Courtesy of the Flash Center for Computational Science.

    The universe is highly magnetic, with everything from stars to planets to galaxies producing their own magnetic fields. Astrophysicists have long puzzled over these surprisingly strong and long-lived fields, with theories and simulations seeking a mechanism that explains their generation.

    Using one of the world’s most powerful laser facilities, a team led by University of Chicago scientists experimentally confirmed one of the most popular theories for cosmic magnetic field generation: the turbulent dynamo. By creating a hot turbulent plasma the size of a penny, which lasts a few billionths of a second, the researchers recorded how the turbulent motions can amplify a weak magnetic field to the strengths of those observed in our sun, distant stars and galaxies.

    The paper, published this week in Nature Communications, is the first laboratory demonstration of a theory explaining the magnetic field of numerous cosmic bodies, which has been debated by physicists for nearly a century. Using the FLASH physics simulation code, developed by the Flash Center for Computational Science at UChicago, the researchers designed an experiment conducted at the OMEGA Laser Facility in Rochester, N.Y. to recreate turbulent dynamo conditions.

    U Rochester Omega Laser

    Confirming decades of numerical simulations, the experiment revealed that turbulent plasma could dramatically boost a weak magnetic field up to the magnitude observed by astronomers in stars and galaxies.

    “We now know for sure that turbulent dynamo exists, and that it’s one of the mechanisms that can actually explain magnetization of the universe,” said Petros Tzeferacos, research assistant professor of astronomy and astrophysics at the University of Chicago and associate director of the Flash Center. “This is something that we hoped we knew, but now we do.”

    A mechanical dynamo produces an electric current by rotating coils through a magnetic field. In astrophysics, dynamo theory proposes the reverse: the motion of electrically-conducting fluid creates and maintains a magnetic field. In the early 20th century, physicist Joseph Larmor proposed that such a mechanism could explain the magnetism of the Earth and sun, inspiring decades of scientific debate and inquiry.

    While numerical simulations demonstrated that turbulent plasma can generate magnetic fields at the scale of those observed in stars, planets and galaxies, creating a turbulent dynamo in the laboratory was far more difficult. Confirming the theory requires producing plasma at an extremely high temperature and volatility to produce the sufficient turbulence to fold, stretch and amplify the magnetic field.

    To design an experiment that creates those conditions, Tzeferacos and colleagues at UChicago and the University of Oxford ran hundreds of two- and three-dimensional simulations with FLASH on the Mira supercomputer at Argonne National Laboratory.

    MIRA IBM Blue Gene Q supercomputer at the Argonne Leadership Computing Facility

    The final setup involved blasting two penny-sized pieces of foil with powerful lasers, propelling two jets of plasma through grids and into collision with each other, creating turbulent fluid motion.

    3

    “People have dreamed of doing this experiment with lasers for a long time, but it really took the ingenuity of this team to make this happen,” said Donald Lamb, the Robert A. Millikan Distinguished Service Professor Emeritus in Astronomy and Astrophysics and director of the Flash Center. “This is a huge breakthrough.”

    The team also used FLASH simulations to develop two independent methods for measuring the magnetic field produced by the plasma: proton radiography, the subject of a recent paper [AIP]from the FLASH group, and polarized light, based on how astronomers measure the magnetic fields of distant objects. Both measurements tracked the growth in mere nanoseconds of the magnetic field from its weak initial state to over 100 kiloGauss—stronger than a high-resolution MRI scanner and a million times stronger than the magnetic field of the Earth.

    “This work opens up the opportunity to experimentally verify ideas and concepts about the origin of magnetic fields in the universe that have been proposed and studied theoretically over the better part of a century,” said Fausto Cattaneo, professor of astronomy and astrophysics at the University of Chicago and a co-author of the paper.

    Now that a turbulent dynamo can be created in a laboratory, scientists can explore deeper questions about its function: How quickly does the magnetic field increase in strength? How strong can the field get? How does the magnetic field alter the turbulence that amplified it?

    “It’s one thing to have well-developed theories, but it’s another thing to really demonstrate it in a controlled laboratory setting where you can make all these kinds of measurements about what’s going on,” Lamb said. “Now that we can do it, we can poke it and probe it.”

    In addition to Tzeferacos and Lamb, UChicago co-authors on the paper include Carlo Graziani and Gianluca Gregori, who is also professor of physics at the University of Oxford. The research was funded by the European Research Council and the U.S. Department of Energy.

    See the full article here .

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  • richardmitnick 10:31 am on January 5, 2018 Permalink | Reply
    Tags: , , Computational astrophysics team uncloaks magnetic fields of cosmic events, Flash Center for Computational Science, , , OMEGA Laser Facility U Rochester, , U Chicago   

    From U Chicago: “Computational astrophysics team uncloaks magnetic fields of cosmic events” 

    U Chicago bloc

    University of Chicago

    January 4, 2018
    Rob Mitchum

    New method enhances study of stars, black holes in laboratory settings.

    1
    Computational astrophysicists describe a new method for acquiring information on experiments using laser beams to reproduce cosmic conditions. Courtesy of
    Lawrence Livermore National Laboratory

    The development of ultra-intense lasers delivering the same power as the entire U.S. power grid has enabled the study of cosmic phenomena such as supernovae and black holes in earthbound laboratories. Now, a new method developed by computational astrophysicists at the University of Chicago allows scientists to analyze a key characteristic of these events: their powerful and complex magnetic fields.

    In the field of high-energy density physics, or HEDP, scientists study a wide range of astrophysical objects—stars, supermassive black holes at the center of galaxies and galaxy clusters—with laboratory experiments as small as a penny and lasting only a few billionths of a second. By focusing powerful lasers on a carefully designed target, researchers can produce plasmas that reproduce conditions observed by astronomers in our sun and distant galaxies.

    Planning these complex and expensive experiments requires large-scale, high-fidelity computer simulation beforehand. Since 2012, the Flash Center for Computational Science of the Department of Astronomy & Astrophysics at UChicago has provided the leading open computer code, called FLASH, for these HEDP simulations, enabling researchers to fine-tune experiments and develop analysis methods before execution at sites such as the National Ignition Facility at Lawrence Livermore National Laboratory or the OMEGA Laser Facility in Rochester, N.Y.


    LLNL/NIF

    2
    OMEGA Laser Facility, U Rochester

    “As soon as FLASH became available, there was kind of a stampede to use it to design experiments,” said Petros Tzeferacos, research assistant professor of astronomy and astrophysics and associate director of the Flash Center.

    During these experiments, laser probe beams can provide researchers with information about the density and temperature of the plasma. But a key measurement, the magnetic field, has remained elusive. To try and tease out magnetic field measurements from extreme plasma conditions, scientists at MIT developed an experimental diagnostic technique that uses charged particles instead, called proton radiography.

    In a new paper for the journal Review of Scientific Instruments, Flash Center scientists Carlo Graziani, Donald Lamb and Tzeferacos, with MIT’s Chikang Li, describe a new method for acquiring quantitative, high-resolution information about these magnetic fields. Their discovery, refined using FLASH simulations and real experimental results, opens new doors for understanding cosmic phenomena.

    “We chose to go after experiments motivated by astrophysics where magnetic fields were important,” said Lamb, the Robert A. Millikan Distinguished Service Professor Emeritus in Astronomy & Astrophysics and director of the Flash Center. “The creation of the code plus the need to try to figure out how to understand what magnetic fields are created caused us to build this software, that can for the first time quantitatively reconstruct the shape and strength of the magnetic field.”

    Skyrocketing experiments

    In proton radiography, energetic protons are shot through the magnetized plasma towards a detector on the other side. As the protons pass through the magnetic field, they are deflected from their path, forming a complex pattern on the detector. These patterns were difficult to interpret, and previous methods could only make general statements about the field’s properties.

    “Magnetic fields play important roles in essentially almost every astrophysical phenomena. If you aren’t able to actually look at what’s happening, or study them, you’re missing a key part of almost every astrophysical object or process that you’re interested in,” said Tzeferacos.

    By conducting simulated experiments with known magnetic fields, the Flash Center team constructed an algorithm that can reconstruct the field from the proton radiograph pattern. Once calibrated computationally, the method was applied to experimental data collected at laser facilities, revealing new insights about astrophysical events.

    The combination of the FLASH code, the development of the proton radiography diagnostic, and the ability to reconstruct magnetic fields from the experimental data, are revolutionizing laboratory plasma astrophysics and HEDP. “The availability of these tools has caused the number of HEDP experiments that study magnetic fields to skyrocket,” said Lamb.

    The new software for magnetic field reconstruction, called PRaLine, will be shared with the community both as part of the next FLASH code release and as a separate component available on GitHub. Lamb and Tzeferacos said they expect it to be used for studying many astrophysics topics, such as the annihilation of magnetic fields in the solar corona; astrophysical jets produced by young stellar objects, the Crab Nebula pulsar, and the supermassive black holes at the center of galaxies; and the amplification of magnetic fields and acceleration of cosmic rays by shocks in supernova remnants.

    “The types of experiments HEDP scientists perform now are very diverse,” said Tzeferacos. “FLASH contributed to this diversity, because it enables you to think outside the box, try different simulations of different configurations, and see what plasma conditions you are able to achieve.”

    The work was funded by grants from the U.S. Department of Energy and the National Science Foundation.

    See the full article here .

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  • richardmitnick 2:45 pm on January 3, 2018 Permalink | Reply
    Tags: "Scientists dig deep in soil for data to improve agriculture, , , , pollution, Soil sensors, Thoreau sensor network, U Chicago   

    From U Chicago: “Scientists dig deep in soil for data to improve agriculture, pollution” 

    U Chicago bloc

    University of Chicago

    January 2, 2018
    Louise Lerner

    1
    UChicago Facilities Services staff Todd Fechner (left) and Kyle Cherry bury a sensor at Stagg Field.

    For as long as humans have been farming, they’ve been trying to figure out what’s going on below ground. Soil is incredibly complex—full of organisms, microbes and chemicals that move and change constantly—and it all feeds into crop health and the Earth’s nutrient cycles in ways that aren’t fully understood. But getting data was a problem, since this generally required taking soil samples and then analyzing them in the lab, which is slow and often expensive.

    Recent advances in wireless data communications and the growing revolution of portable, cheap sensors have made it possible for UChicago scientists, including Profs. Monisha Ghosh and Supratik Guha, both affiliated with the Institute for Molecular Engineering, to start a pilot program to take real-time soil measurements—and they started in their own campus.

    Their project, called the Thoreau sensor network, buried more than 30 sensing boxes in a variety of different locations around the UChicago campus.

    5
    The sensor boxes are buried with the tip of the antenna six to eight inches underground, with sensors extending farther down. Photo by William Kent.

    Each one is a cube about five inches square, containing four sensors that measure the soil’s water content, salt, temperature and water potential, the measure of how readily the soil holds or drains moisture. Twice an hour, a tiny radio transmitter and antenna—fully buried underground—sends a burst of data to the receiver, located atop the William Eckhardt Research Center.

    For the hardware, they used commercial sensors that already exist. But there were a lot of questions about how the sensors might behave underground: Can the signals make it to the receivers above ground? Does the battery die faster? What happens to the machinery during freeze-thaw cycles?

    “This test run provides us extremely helpful real-world data on how one could actually run a sensor network like this,” Ghosh said. “For example, the Chicago winter gave us some very helpful information.” (A few of the sensors didn’t survive last winter.)

    There were also questions about whether the radio signals would be able to be transmitted from below the ground. The research team found that they could successfully transmit over distances of one and a half miles, even though the antennas were buried six to eight inches below the surface of the ground.

    Wet soil appears to inhibit the signal, they said, but the biggest issue so far is battery life. The group of undergraduate students working on the project have been a big help, Ghosh said. “They’ve come up with some really excellent ideas for saving battery life,” including a low-power timer that puts the sensor to sleep in between its 30-minute wake-up calls.

    Seasons of change

    2
    Arturo Ortiz of UChicago Facilities Services buries a sensor in another location; flowerbeds offer a different soil structure and composition from other soil. Photo by William Kent.

    The land that is now the University of Chicago campus was once sand, marsh and prairie at the edge of Lake Michigan. Now it’s home to a network of streets, century-old buildings, quadrangles, athletic fields, flowerbeds and libraries. Each use has different impacts on the soil below—and these differences show up in the data.

    The study is just underway, but Ghosh said they’ve seen some interesting trends and questions in their data. “For example, we believe we’re seeing patterns in how water leaves different types of soil after a rainfall,” she said, as well as moisture differences in the growing season versus the winter.

    As a materials scientist, Guha is interested in the sensor hardware. He heads the Center for Nanoscale Materials at Argonne National Laboratory, where research on developing new capabilities for sensors is underway.

    “For example, what we would really love to do is to make a sensor that can measure soil nitrates,” he said. This would provide a way to measure how much of the fertilizer that farmers apply to their soil gets to the plants. It’s thought that less than half of the nitrogen goes to plants; the rest of it likely washes off and pollutes rivers, lakes and oceans.

    “There’s a lot we’d like to do,” Ghosh said. “Can we hook sprinklers up to receive input from our sensors? How far down is the right depth for the best data? How much can we extend the range of how far a sensor can be from the receiver? Can we boost the signal to reach from beneath paved areas or sidewalks?”

    A complementary project is ongoing in India, testing the water quality of the Godavari River in southern India and how it reacts to weather, pollution, fishing and general use. In this case, a boat carries a mobile sensing platform equipped with GPS along the river every few days, enabling scientists to map the river chemistry.

    “Those results have been spectacular,” Guha said. “We’re seeing that dynamic mapping of river water quality can accurately help pinpoint and assess pollution sources.”

    Students get hands-on experience

    4
    Summer interns Cayla Hamann (background) and Cheng Chang (foreground) help install a water sensor on UChicago campus. Photo by Xufeng Zhang.

    The researchers discussed the results at a Nov. 1-2 workshop at UChicago for the emerging field of soil sensing, funded by the National Science Foundation. The goal was to share knowledge on the pursuit of better subterranean sensing networks by gathering experts from fields including microelectronics, machine learning and modeling, together with those who study the microbes and physics of soil directly.

    The UChicago students who have worked on the Thoreau project said they were getting hands-on experience with sensors as well as programming.

    Undergraduate students William Kent and Jacob Gold worked on the site’s website, including different ways for users to download the data. “We were given a ton of freedom and flexibility to plan out how we would convey that data,” said Gold, a third-year computer science major.

    Kent, a second-year and molecular engineering major, agreed. “They tell us the user needs to be able to do this, and we figure out how to make it work. I don’t think a lot of our peers really get that creative license in their research projects,” he said. “I feel like we’re really creating something.”

    Undergraduate student Arseniy Andreyev also designed and built much of the initial hardware, working with postdoctoral scientist Xufeng Zhang, Guha said.

    See the full article here .

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    One of the world’s premier academic and research institutions, the University of Chicago has driven new ways of thinking since our 1890 founding. Today, UChicago is an intellectual destination that draws inspired scholars to our Hyde Park and international campuses, keeping UChicago at the nexus of ideas that challenge and change the world.

     
  • richardmitnick 2:02 pm on January 2, 2018 Permalink | Reply
    Tags: , , , , Scientists describe how solar system could have formed in bubble around giant star, U Chicago   

    From U Chicago: “Scientists describe how solar system could have formed in bubble around giant star” 

    U Chicago bloc

    University of Chicago

    December 22, 2017
    Louise Lerner

    1
    This simulation shows how bubbles form over the course of 4.7 million years from the intense stellar winds off a massive star. UChicago scientists postulated how our own solar system could have formed in the dense shell of such a bubble. Courtesy of V. Dwarkadas & D. Rosenberg.

    Despite the many impressive discoveries humans have made about the universe, scientists are still unsure about the birth story of our solar system.

    Scientists with the University of Chicago have laid out a comprehensive theory for how our solar system could have formed in the wind-blown bubbles around a giant, long-dead star. Published Dec. 22 in The Astrophysical Journal, the study addresses a nagging cosmic mystery about the abundance of two elements in our solar system compared to the rest of the galaxy.

    The general prevailing theory is that our solar system formed billions of years ago near a supernova. But the new scenario instead begins with a giant type of star called a Wolf-Rayet star, which is more than 40 to 50 times the size of our own sun. They burn the hottest of all stars, producing tons of elements which are flung off the surface in an intense stellar wind. As the Wolf-Rayet star sheds its mass, the stellar wind plows through the material that was around it, forming a bubble structure with a dense shell.

    “The shell of such a bubble is a good place to produce stars,” because dust and gas become trapped inside where they can condense into stars, said coauthor Nicolas Dauphas, professor in the Department of Geophysical Sciences. The authors estimate that 1 percent to 16 percent of all sun-like stars could be formed in such stellar nurseries.

    This setup differs from the supernova hypothesis in order to make sense of two isotopes that occur in strange proportions in the early solar system, compared to the rest of the galaxy. Meteorites left over from the early solar system tell us there was a lot of aluminium-26. In addition, studies, including a 2015 one by Dauphas [The Astrophysical Journal] and a former student, increasingly suggest we had less of the isotope iron-60.

    This brings scientists up short, because supernovae produce both isotopes. “It begs the question of why one was injected into the solar system and the other was not,” said coauthor Vikram Dwarkadas, a research associate professor in Astronomy and Astrophysics.

    This brought them to Wolf-Rayet stars, which release lots of aluminium-26, but no iron-60.

    “The idea is that aluminum-26 flung from the Wolf-Rayet star is carried outwards on grains of dust formed around the star. These grains have enough momentum to punch through one side of the shell, where they are mostly destroyed—trapping the aluminum inside the shell,” Dwarkadas said. Eventually, part of the shell collapses inward due to gravity, forming our solar system.

    3
    Slices of a simulation showing how bubbles around a massive star evolve over the course of millions of years (moving clockwise from top left). Courtesy of V. Dwarkadas & D. Rosenberg

    As for the fate of the giant Wolf-Rayet star that sheltered us: Its life ended long ago, likely in a supernova explosion or a direct collapse to a black hole. A direct collapse to a black hole would produce little iron-60; if it was a supernova, the iron-60 created in the explosion may not have penetrated the bubble walls, or was distributed unequally.

    Other authors on the paper included UChicago undergraduate student Peter Boyajian and Michael Bojazi and Brad Meyer of Clemson University.

    Funding: NASA

    See the full article here .

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  • richardmitnick 1:35 pm on September 22, 2017 Permalink | Reply
    Tags: Dauphas and his team looked at titanium in the shales over time, , Geologists often look at a particular kind of rock called shales, , If you fertilize the ocean with phosphorus life will bloom, Plate techtonics is believed to be needed to create felsic rock, Study suggests significant tectonic action was already taking place 3.5 billion years ago—about half a billion years earlier than currently thought, The flood of oxygen came from a surge of photosynthetic microorganisms - cyanobacteria, The titanium timeline suggests that the primary trigger of the surge of phosphorus was the change in the makeup of mafic rock over time, Tracing the path of metallic element titanium through the Earth’s crust across time, U Chicago   

    From U Chicago: “Study suggests tectonic plates began moving half a billion years earlier than thought” 

    U Chicago bloc

    University of Chicago

    September 21, 2017
    Louise Lerner

    1
    While previous studies had argued that Earth’s crust 3.5 billion years ago looked like these Hawaiian lavas, a new study led by UChicago scientists suggests by then much of it had already been transformed into lighter-colored felsic rock by plate tectonics.
    Photo by Basil Greber

    The Earth’s history is written in its elements, but as the tectonic plates slip and slide over and under each other over time, they muddy that evidence—and with it the secrets of why Earth can sustain life.

    A new study led by UChicago geochemists rearranges the picture of the early Earth by tracing the path of metallic element titanium through the Earth’s crust across time. The research, published Sept. 22 in Science, suggests significant tectonic action was already taking place 3.5 billion years ago—about half a billion years earlier than currently thought.

    The crust was once made of uniformly dark, magnesium- and iron-rich mafic minerals. But today the crust looks very different between land and ocean: The crust on land is now a lighter-colored felsic, rich in silicon and aluminum. The point at which these two diverged is important, since the composition of minerals affects the flow of nutrients available to the fledgling life struggling to survive on Earth.

    “This question has been discussed since geologists first started thinking about rocks,” said lead author Nicolas Dauphas, the Louis Block Professor and head of the Origins Laboratory in the Department of the Geophysical Sciences and the Enrico Fermi Institute. “This result is a surprise and certainly an upheaval in that discussion.”

    To reconstruct the crust changing over time, geologists often look at a particular kind of rock called shales, made up of tiny bits of other rocks and minerals that are carried by water into mud deposits and compressed into rock. The only problem is that scientists have to adjust the numbers to account for different rates of weathering and transport. “There are many things that can foul you up,” Dauphas said.

    To avoid this issue, Dauphas and his team looked at titanium in the shales over time. This element doesn’t dissolve in water and isn’t taken up by plants in nutrient cycles, so they thought the data would have fewer biases with which to contend.

    They crushed samples of shale rocks of different ages from around the world and checked in what form its titanium appeared. The proportions of titanium isotopes present should shift as the rock changes from mafic to felsic. Instead, they saw little change over three and a half billion years, suggesting that the transition must have occurred before then.

    2
    These granite peaks are an example of felsic rock, created via plate tectonics. Photo by Basil Greber

    This also would mark the beginning of plate tectonics, since that process is believed to be needed to create felsic rock.

    “With a null response like that, seeing no change, it’s difficult to imagine an alternate explanation,” said Matouš Ptáček, a UChicago graduate student who co-authored the study.

    “Our results can also be used to track the average composition of the continental crust through time, allowing us to investigate the supply of nutrients to the oceans going back 3.5 billion years ago,” said Nicolas Greber, the first author of the paper, then a postdoctoral researcher at UChicago and now with the University of Geneva.

    Phosphorous leads to life

    The question about nutrients is important for our understanding of the circumstances around a mysterious but crucial turning point called the great oxygenation event. This is when oxygen started to emerge as an important constituent of Earth’s atmosphere, wreaking a massive change on the planet—and making it possible for multi-celled beings to evolve.

    The flood of oxygen came from a surge of photosynthetic microorganisms; and in turn their work was fostered by a surge of nutrients to the oceans, particularly phosphorus. “Phosphorus is the most important limiting nutrient in the modern ocean. If you fertilize the ocean with phosphorus, life will bloom,” Dauphas said.

    The titanium timeline suggests that the primary trigger of the surge of phosphorus was the change in the makeup of mafic rock over time. As the Earth cooled, the mafic rock coming out of volcanoes and underground melts became richer in phosphorus.

    “We’ve known for a long time that mafic rock changed over time, but what we didn’t know was that their contribution to the crust has stayed rather consistent,” Ptáček said.

    Other institutions on the study were the University of California-Riverside, University of Oregon-Eugene and the University of Johannesburg.

    See the full article here .

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    An intellectual destination

    One of the world’s premier academic and research institutions, the University of Chicago has driven new ways of thinking since our 1890 founding. Today, UChicago is an intellectual destination that draws inspired scholars to our Hyde Park and international campuses, keeping UChicago at the nexus of ideas that challenge and change the world.

     
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