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  • richardmitnick 1:20 pm on December 3, 2022 Permalink | Reply
    Tags: "DOE": diffractive optical element, "PAM": Photoacoustic microscopy, "Seeing More with a Needle-Shaped Laser", , , , , , , The California Institute of Technology   

    From The California Institute of Technology: “Seeing More with a Needle-Shaped Laser” 

    Caltech Logo

    From The California Institute of Technology

    12.1.22
    Emily Velasco
    (626) 372‑0067
    evelasco@caltech.edu

    Photoacoustic microscopy (PAM) is a relatively new imaging technique that uses laser light to induce ultrasonic vibrations in tissue. These ultrasonic vibrations, along with a computer that processes them, can then be used to create an image of the structures of the tissue in much the same way ultrasound imaging works.

    1
    Lihong Wang. Credit: Caltech.

    In the last few years, Lihong Wang, Caltech’s Bren Professor of Medical Engineering and Electrical Engineering, has developed PAM technologies that can image changing blood flow in the brain, detect cancerous tissue, and even identify individual cancer cells.

    However, one limitation of high-resolution (i.e., optical-resolution) PAM has been its narrow depth of field, meaning that it can only focus on a thin layer (approximately 30 micrometers, or about the length of one skin cell, with one to two micrometers of resolution) of tissue at a time. To see something above or below the plane that the device is viewing, it needs to refocus above or below that plane. For comparison, imagine a person putting on reading glasses to do a crossword puzzle.

    3
    Depth of field: At left, an image of a tree branch taken with a shallow depth of field. Only the foreground is in focus. At right, an image of the same branch taken with a deep depth of field. Both the foreground and background are in focus. Credit: NightWolf1223/Wikimedia Commons.

    In a new paper in the journal Nature Photonics [below], Wang and his research team show how they developed a new variant of PAM called needle-shaped beam photoacoustic microscopy, or NB-PAM, which that has a depth of field nearly 14 times greater than what was achievable before. This means NB-PAM can create 3-D imagery of samples without refocusing and better image samples with uneven surfaces.

    4
    An image of mouse liver tissue taken with traditional photoacoustic microscopy (left) compared to an image of mouse liver tissue taken with needle-shaped beam photoacoustic microscopy (right). In the image at the right, structures are in focus over a greater range of depth. Credit: Caltech.

    “Some applications, such as studying tissue samples without needing to use a microscope slide, require imaging of uneven surfaces at high spatial resolution,” says Rui Cao, lead author and postdoctoral scholar research associate in medical engineering. “Conventional PAM grapples with the trade-off between resolution and depth of field, which has been overcome by our new technology.”

    NB-PAM improves its depth of field over its related PAM technologies by using a beam of laser light that is longer and thinner, hence “needle shaped.” This change in the optical characteristics of the beam avoids some of the drawbacks associated with other attempts to increase the depth of field of PAM technology, such as working more slowly, or requiring more computer processing power.

    5
    Traditional photoacoustic microscopy (PAM) (left) compared to needle-shaped photoacoustic microscopy (NB-PAM) (right). In traditional PAM, only objects near the focal point of the laser are imaged sharply. In NB-PAM, the longer, narrower beam allows objects over a greater range of depth to be clearly imaged. Credit: Caltech.

    This needle-shaped beam is created using a specialized item known as a diffractive optical element (DOE). To the casual observer, a DOE looks like a tiny sheet of glass, but it is actually a piece of fused silica with precise patterns engraved on its surface. Those patterns reshape the beam of light that is used for imaging, so that it no longer focuses to a sharp point along the propagation axis but is instead drawn out into a long thin neck. Consequently, it is able to clearly image objects over a greater range of depths.

    That greater depth of field was demonstrated by the researchers in two ways: imaging fresh organ samples using an ultraviolet laser and imaging in vivo mouse brain vasculature using a blue laser.

    “This technology provides new opportunities for studying tissue samples during surgery, which would allow complete removal of cancer cells and maximal preservation of normal ones,” says Wang, who is also the Andrew and Peggy Cherng Medical Engineering Leadership Chair; Executive Officer for Medical Engineering. “Translation into the operating room is a natural future avenue of research.”

    6
    Rui Cao, lead author and postdoctoral scholar research associate in medical engineering. Credit: Rui Cao.

    Science paper:
    Nature Photonics

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 9:48 pm on November 30, 2022 Permalink | Reply
    Tags: "Einstein–Rosen bridges", "EPR": Einstein-Podolsky-Rosen, "ER = EPR" theory, "Physicists observe wormhole dynamics using a quantum computer", "SYK" model: Subir Sachdev- Jinwu Ye- Alexei Kitaev, , , , Juan Maldacena and Leonard Susskind in 2013 first proposed the notion that wormholes and quantum physics may have a connection., , , , Some theoretical wormhole ideas could be studied more deeply by doing experiments on quantum processors., The California Institute of Technology, The physicists [Juan Maldacena and Leonard Susskind] speculated that wormholes (or "ER") were equivalent to entanglement., The research is a step toward studying "quantum gravity" in the lab., The term "wormhole" itself was coined by physicist John Wheeler in the 1950s.   

    From The California Institute of Technology: “Physicists observe wormhole dynamics using a quantum computer” 

    Caltech Logo

    From The California Institute of Technology

    11.30.22
    Whitney Clavin
    (626) 395‑1944
    wclavin@caltech.edu

    1
    Artwork depicting a quantum experiment that studies traversable wormholes. Credit: inqnet/A. Mueller (Caltech)

    The research is a step toward studying “quantum gravity” in the lab.

    Scientists have, for the first time, developed a quantum experiment that allows them to study the dynamics, or behavior, of a special kind of theoretical wormhole. The experiment has not created an actual wormhole (a rupture in space and time), rather it allows researchers to probe connections between theoretical wormholes and quantum physics, a prediction of so-called quantum gravity. Quantum gravity refers to a set of theories that seek to connect gravity with quantum physics, two fundamental and well-studied descriptions of nature that appear inherently incompatible with each other.

    “We found a quantum system that exhibits key properties of a gravitational wormhole yet is sufficiently small to implement on today’s quantum hardware,” says Maria Spiropulu, the principal investigator of the U.S. Department of Energy Office of Science research program Quantum Communication Channels for Fundamental Physics (QCCFP) and the Shang-Yi Ch’en Professor of Physics at Caltech. “This work constitutes a step toward a larger program of testing quantum gravity physics using a quantum computer. It does not substitute for direct probes of quantum gravity in the same way as other planned experiments that might probe quantum gravity effects in the future using quantum sensing, but it does offer a powerful testbed to exercise ideas of quantum gravity.”

    The research will be published December 1 in the journal Nature [below]. The study’s first authors are Daniel Jafferis of Harvard University and Alexander Zlokapa (BS ’21), a former undergraduate student at Caltech who started on this project for his bachelor’s thesis with Spiropulu and has since moved on to graduate school at MIT.

    Wormholes are bridges between two remote regions in spacetime. They have not been observed experimentally, but scientists have theorized about their existence and properties for close to 100 years. In 1935, Albert Einstein and Nathan Rosen described wormholes as tunnels through the fabric of spacetime in accordance with Einstein’s General Theory of Relativity, which describes gravity as a curvature of spacetime. Researchers call wormholes “Einstein–Rosen bridges” after the two physicists who invoked them, while the term “wormhole” itself was coined by physicist John Wheeler in the 1950s.

    The notion that wormholes and quantum physics, specifically entanglement (a phenomenon in which two particles can remain connected across vast distances), may have a connection was first proposed in theoretical research by Juan Maldacena and Leonard Susskind in 2013. The physicists speculated that wormholes (or “ER”) were equivalent to entanglement (also known as “EPR” after Albert Einstein, Boris Podolsky [PhD ’28], and Nathan Rosen, who first proposed the concept). In essence, this work established a new kind of theoretical link between the worlds of gravity and quantum physics. “It was a very daring and poetic idea,” says Spiropulu of the “ER = EPR” work.

    Later, in 2017, Jafferis, along with his colleagues Ping Gao and Aron Wall, extended the “ER = EPR” idea to not just wormholes but traversable wormholes. The scientists concocted a scenario in which negative repulsive energy holds a wormhole open long enough for something to pass through from one end to the other. The researchers showed that this gravitational description of a traversable wormhole is equivalent to a process known as quantum teleportation. In quantum teleportation, a protocol that has been experimentally demonstrated over long distances via optical fiber and over the air, information is transported across space using the principles of quantum entanglement.

    The present work explores the equivalence of wormholes with quantum teleportation. The Caltech-led team performed the first experiments that probe the idea that information traveling from one point in space to another can be described in either the language of gravity (the wormholes) or the language of quantum physics (quantum entanglement).

    A key finding that inspired possible experiments occurred in 2015, when Caltech’s Alexei Kitaev, the Ronald and Maxine Linde Professor of Theoretical Physics and Mathematics, showed that a simple quantum system could exhibit the same duality later described by Gao, Jafferis, and Wall, such that the model’s quantum dynamics are equivalent to quantum gravity effects. This Sachdev–Ye–Kitaev, or SYK model (named after Kitaev, and Subir Sachdev and Jinwu Ye, two other researchers who worked on its development previously) led researchers to suggest that some theoretical wormhole ideas could be studied more deeply by doing experiments on quantum processors.

    Furthering these ideas, in 2019, Jafferis and Gao showed that by entangling two “SYK” models, researchers should be able to perform wormhole teleportation and thus produce and measure the dynamical properties expected of traversable wormholes.

    In the new study, the team of physicists performed this type of experiment for the first time. They used a “baby” “SYK”-like model prepared to preserve gravitational properties, and they observed the wormhole dynamics on a quantum device at Google, namely the Sycamore quantum processor.

    To accomplish this, the team had to first reduce the “SYK” model to a simplified form, a feat they achieved using machine learning tools on conventional computers.

    “We employed learning techniques to find and prepare a simple “SYK”-like quantum system that could be encoded in the current quantum architectures and that would preserve the gravitational properties,” says Spiropulu. “In other words, we simplified the microscopic description of the “SYK’ quantum system and studied the resulting effective model that we found on the quantum processor. It is curious and surprising how the optimization on one characteristic of the model preserved the other metrics! We have plans for more tests to get better insights on the model itself.”

    In the experiment, the researchers inserted a qubit—the quantum equivalent of a bit in conventional silicon-based computers—into one of their “SYK”-like systems and observed the information emerge from the other system. The information traveled from one quantum system to the other via quantum teleportation—or, speaking in the complementary language of gravity, the quantum information passed through the traversable wormhole.

    “We performed a kind of quantum teleportation equivalent to a traversable wormhole in the gravity picture. To do this, we had to simplify the quantum system to the smallest example that preserves gravitational characteristics so we could implement it on the Sycamore quantum processor at Google,” says Zlokapa.

    Co-author Samantha Davis, a graduate student at Caltech, adds, “It took a really long time to arrive at the results, and we surprised ourselves with the outcome.”

    “The near-term significance of this type of experiment is that the gravitational perspective provides a simple way to understand an otherwise mysterious many-particle quantum phenomenon,” says John Preskill, the Richard P. Feynman Professor of Theoretical Physics at Caltech and director of the Institute for Quantum Information and Matter (IQIM). “What I found interesting about this new Google experiment is that, via machine learning, they were able to make the system simple enough to simulate on an existing quantum machine while retaining a reasonable caricature of what the gravitation picture predicts.”

    In the study, the physicists report wormhole behavior expected both from the perspectives of gravity and from quantum physics. For example, while quantum information can be transmitted across the device, or teleported, in a variety of ways, the experimental process was shown to be equivalent, at least in some ways, to what might happen if information traveled through a wormhole. To do this, the team attempted to “prop open the wormhole” using pulses of either negative repulsive energy pulse or the opposite, positive energy. They observed key signatures of a traversable wormhole only when the equivalent of negative energy was applied, which is consistent with how wormholes are expected to behave.

    “The high fidelity of the quantum processor we used was essential,” says Spiropulu. “If the error rates were higher by 50 percent, the signal would have been entirely obscured. If they were half we would have 10 times the signal!”

    In the future, the researchers hope to extend this work to more complex quantum circuits. Though bona fide quantum computers may still be years away, the team plans to continue to perform experiments of this nature on existing quantum computing platforms.

    “The relationship between quantum entanglement, spacetime, and quantum gravity is one of the most important questions in fundamental physics and an active area of theoretical research,” says Spiropulu. “We are excited to take this small step toward testing these ideas on quantum hardware and will keep going.”

    More information can be found at the Alliance for Quantum Technologies website: https://inqnet.caltech.edu/wormhole2022.

    Science paper:
    Nature

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 5:29 pm on November 30, 2022 Permalink | Reply
    Tags: "New theory explains magnetic trends in high-temperature superconductors", , For decades researchers have sought out superconductors that work at room temperature., , The California Institute of Technology, There are some materials that have no electrical resistance whatsoever. These are called superconductors., Unique properties are used in technologies ranging from magnetic resonance imaging (MRI) to levitating trains [Maglev].   

    From The California Institute of Technology: “New theory explains magnetic trends in high-temperature superconductors” 

    Caltech Logo

    From The California Institute of Technology

    11.30.22
    Emily Velasco
    (626) 372‑0067
    evelasco@caltech.edu

    1
    In just about any situation in which electricity is being used, whether it is lighting a bedroom at night, keeping frozen food cold, or powering a car that is taking a commuter to work, some of that electrical energy is lost as heat. This is called resistance. Materials with lower resistance are better at conducting electricity while materials with higher resistance are worse at it.

    Though nearly all conductors exhibit some resistance, there are some materials that have no electrical resistance whatsoever. These are called superconductors, and their unique properties are used in technologies ranging from magnetic resonance imaging (MRI) to levitating trains.

    However, most superconductors only superconduct when they are cold—really cold. Even so-called “high temperature” superconductors need to be cooled with liquid nitrogen to roughly -200 degrees Celsius to work.

    That need for intense cooling adds a big complication to the use of superconductors. For decades, researchers have sought out superconductors that work at room temperature. Currently, at normal atmospheric pressure, the class of high temperature superconductors known as the cuprates—compounds containing both copper and oxygen atoms—come the closest, with the best-performing cuprate able to superconduct at temperatures as “warm” as -140 degrees Celsius.

    Since -140 degrees Celsius is still quite cold, there is a long way to go before cuprates can be called room-temperature superconductors, and further advancement of these superconductors has been hampered by the fact that no one has figured out how cuprate superconductors work.

    2
    Garnet Chan, Bren Professor of Chemistry at Caltech. Credit: Caltech.

    But now, researchers in the group of Garnet Chan, Caltech’s Bren Professor of Chemistry, have developed a theory that explains some of the magnetic properties of cuprate superconductors. Cuprate superconducting materials exhibit a layer effect, where their magnetic and superconducting properties are enhanced as more layers of the constituent copper and oxygen atoms are brought together. In a paper published in the journal Science [below], Chan and his coauthors explain how the magnetic layer effect arises from fluctuations of the electrons between the copper and oxygen atoms and their surrounding atoms.

    “This is a first step toward understanding the governing principles behind the superconducting layer effect, and what controls the superconducting temperature in superconductors more generally,” says Zhihao Cui, chemistry graduate student and first author of the study.

    3
    Zhihao Cui. Credit: Caltech.

    Science paper:
    Science

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct.


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 1:52 pm on November 26, 2022 Permalink | Reply
    Tags: "Machine Learning Tools Automatically Classify 1000 Supernovae", Algorithm helps astronomers sift through discoveries from Zwicky Transient Facility, , , , , Fremling and colleagues are currently working to extend the capabilities of the algorithm to classify other types of supernovae in the near future., The California Institute of Technology, The team developed "SNIascore" for the task of classifying candidate supernovae.   

    From The California Institute of Technology: “Machine Learning Tools Automatically Classify 1000 Supernovae” 

    Caltech Logo

    From The California Institute of Technology

    1
    Credit: Caltech

    11.22.22
    Whitney Clavin
    (626) 395‑1944
    wclavin@caltech.edu

    Algorithm helps astronomers sift through discoveries from Zwicky Transient Facility

    Astronomers at Caltech have used a machine learning algorithm to classify 1,000 supernovae completely autonomously. The algorithm was applied to data captured by the Zwicky Transient Facility, or ZTF, a sky survey instrument based at Caltech’s Palomar Observatory.

    “We needed a helping hand, and we knew that once we trained our computers to do the job, they would take a big load off our backs,” says Christoffer Fremling, a staff astronomer at Caltech and the mastermind behind the new algorithm, dubbed SNIascore. “‘SNIascore’ classified its first supernova in April 2021, and, a year and a half later, we are hitting a nice milestone of 1,000 supernovae.”

    1
    Christoffer Fremling. Credit: Caltech.


    Machine Learning Tools Automatically Classify 1,000 Supernovae. 4.1.21
    The machine learning algorithm classified 1,000 supernovae completely autonomously using data captured by ZTF, which is based at Caltech’s Palomar Observatory near San Diego. The blank area in the video at bottom right represents regions in the southern skies that cannot be seen from Palomar Mountain.

    ZTF scans the night skies every night to look for changes called transient events. This includes everything from moving asteroids to black holes that have just eaten stars to exploding stars known as supernovae. ZTF sends out hundreds of thousands of alerts a night to astronomers around the world, notifying them of these transient events. The astronomers then use other telescopes to follow up and investigate the nature of the changing objects. So far, ZTF data have led to the discovery of thousands of supernovae.

    But with relentless amounts of data pouring in every night, members of the ZTF team cannot sort through all the data on their own.

    “The traditional notion of an astronomer sitting at the observatory and sieving through telescope images carries a lot of romanticism but is drifting away from reality,” says Matthew Graham, project scientist for ZTF and a research professor of astronomy at Caltech.

    2
    Matthew Graham. Credit: Caltech.

    Instead, the team has developed machine learning algorithms to aid in the searches. They developed “SNIascore” for the task of classifying candidate supernovae. Supernovae come in two broad classes: Type I and Type II. Supernovae of Type I are devoid of hydrogen, while supernovae of Type II are rich in hydrogen. The most common Type I supernova occurs when a massive star steals matter from a neighboring star, which triggers a thermonuclear explosion. A Type II supernova occurs when a massive star collapses under its own gravity.

    Currently, “SNIascore” can classify what are known as Type Ia supernovae, or the “standard candles” in the sky.

    These are dying stars that go bang with a thermonuclear explosion of a consistent strength. Type Ia supernovae allow astronomers to measure the expansion rate of the universe. Fremling and colleagues are currently working to extend the capabilities of the algorithm to classify other types of supernovae in the near future.

    Every night, after ZTF has captured flashes in the sky that could be supernovae, it sends the data to a spectrograph at Palomar that is housed in a dome just few hundred meters away, called the SEDM (Spectral Energy Distribution Machine). “SNIascore” works with SEDM to then classify which supernovae are likely Type Ia. The result is that the ZTF team is rapidly building a more reliable data set of supernovae for astronomers to further investigate and to ultimately learn about the physics of the powerful stellar explosions.

    “‘SNIascore’ is remarkably accurate. After 1,000 supernovae, we have seen how the algorithm performs in the real world,” Fremling says. “We have found no clearly misclassified events since launching back in April 2021, and we are now planning to implement the same algorithm with other observing facilities.”

    Ashish Mahabal, who leads machine learning activities for ZTF and serves as the lead computational and data scientist at Caltech’s Center for Data Driven Discovery, adds, “This work demonstrates well how machine learning applications are coming of age in near real-time astronomy.”

    4
    Ashish Mahabal. Credit: Caltech.

    To learn more about the new algorithm, read the full story at the ZTF website.

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct.


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 1:15 pm on November 26, 2022 Permalink | Reply
    Tags: "Pushing the Boundaries of Fluid Equations", 3D Euler singularity, , , , Navier–Stokes equations-the motion of fluids in nature, , The "Navier-Stokes Millennium Problem", The California Institute of Technology   

    From The California Institute of Technology: “Pushing the Boundaries of Fluid Equations” 

    Caltech Logo

    From The California Institute of Technology

    11.22.22

    Written by
    Ben Peltz

    Contact
    Emily Velasco
    (626) 372‑0067
    evelasco@caltech.edu

    1
    Credit: Caltech.

    The motion of fluids in nature, including the flow of water in our oceans, the formation of tornadoes in our atmosphere, and the flux of air surrounding airplanes, have long been described and simulated by what are known as the Navier–Stokes equations.

    Yet, mathematicians do not have a complete understanding of these equations. While they are a useful tool for predicting the flow of fluids, we still do not know if they accurately describe fluids in all possible scenarios. This led the Clay Mathematics Institute of New Hampshire to label the Navier–Stokes equations as one of its seven Millennium Problems: the seven most pressing unsolved problems in all of mathematics.

    The Navier–Stokes Equation Millennium Problem asks mathematicians to prove whether “smooth” solutions always exist for the Navier–Stokes equations. Put simply, smoothness refers to whether equations of this type behave in a predictable way that makes sense. Imagine a simulation in which a foot presses the gas pedal of a car, and the car accelerates to 10 miles per hour (mph), then to 20 mph, then to 30 mph, and then to 40 mph. However, if the foot presses the gas pedal and the car accelerates to 50 mph, then to 60 mph, then instantly to an infinite number of miles per hour, you would say there is something wrong with the simulation.

    This is what mathematicians hope to determine for the Navier–Stokes equations. Do they always simulate fluids in a way that makes sense, or are there some situations in which they break down?

    For an in-depth explanation of this topic, see the blog post “Why global regularity for Navier-Stokes is hard” by Australian mathematician Terence Tao.

    In a paper published on the preprint site arXiv [below] on October 19, Caltech’s Thomas Hou, the Charles Lee Powell Professor of Applied and Computational Mathematics, and Jiajie Chen (PhD ’22) of New York University’s Courant Institute, provide a proof that resolves a longstanding open problem for the so-called 3D Euler singularity. The 3D Euler equation is a simplification of the Navier–Stokes equations, and a singularity is the point where an equation starts to break down or “blow up,” meaning it can suddenly become chaotic without warning (like the simulated car accelerating to an infinite number of miles per hour). The proof is based on a scenario first proposed by Hou and his former postdoc, Guo Luo, in 2014.

    Hou’s computation with Luo in 2014 discovered a new scenario that showed the first convincing numerical evidence for a 3D Euler blowup, whereas previous attempts to discover a 3D Euler blowup were either inconclusive or not reproduceable.

    In the latest paper, Hou and Chen show definitive and irrefutable proof of Hou and Luo’s work involving 3D Euler equation blowup. “It starts from something that behaves nicely, but then somehow evolves in a way where it becomes catastrophic,” Hou says.

    “For the first ten years of my work, I believed there was no Euler blowup,” says Hou. After more than a decade of research since, Hou has not only proved his former self wrong, he’s settled a centuries-old mathematics mystery.

    “This breakthrough is a testament to Dr. Hou’s tenacity in addressing the Euler problem and the intellectual environment that Caltech nutures,” says Harry A. Atwater, Otis Booth Leadership Chair of the Division of Engineering and Applied Science, Howard Hughes Professor of Applied Physics and Materials Science, and director of the Liquid Sunlight Alliance. “Caltech empowers researchers to apply sustained creative effort on complex problems – even over decades – to achieve extraordinary results.”

    Hou and colleagues’ combined effort in proving the existence of blowup with the 3D Euler equation is a major breakthrough in its own right, but also represents a huge leap forward in tackling the “Navier-Stokes Millennium Problem”. If the Navier–Stokes equations could also blow up, it would mean something is awry with one of the most fundamental equations used to describe nature.

    “The whole framework that we set up for this analysis would be tremendously helpful for Navier–Stokes,” Hou says. “I have recently identified a promising blowup candidate for Navier-Stokes. We just need to find the right formulation to prove the blowup of the Navier-Stokes .”

    2
    Thomas Hou. Credit: Vicki Chiu/Caltech.

    3
    Jiajie Chen. Credit: Briana Ticehurst/Caltech.

    Science paper:
    arXiv
    See the science paper for instructive material with images.

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct.


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 4:37 pm on November 17, 2022 Permalink | Reply
    Tags: "Electronic/Photonic Chip Sandwich Pushes Boundaries of Computing and Data Transmission Efficiency", , , Data processing is done on electronic circuits while data transmission is most efficiently done using photonics., , Managing the load of thousands of terabytes of data going in and out every second., The California Institute of Technology, The new design could influence the future of data centers that manage very high volumes of data communication., The resulting optimized interface between the two chips allows them to transmit 100 gigabits of data per second while producing just 2.4 pico-Joules per transmitted bit.,   

    From The California Institute of Technology And The University of Southampton (UK) : “Electronic/Photonic Chip Sandwich Pushes Boundaries of Computing and Data Transmission Efficiency” 

    Caltech Logo

    From The California Institute of Technology

    And

    U Southampton bloc

    The University of Southampton (UK)

    11.17.22
    Robert Perkins
    (626) 395‑1862
    rperkins@caltech.edu

    1
    The chip sandwich: an electronics chip (the smaller chip on the top) integrated with a photonics chip, sitting atop a penny for scale. (Credit: Arian Hashemi Talkhooncheh)

    Engineers at Caltech and the University of Southampton in England have collaboratively designed an electronics chip integrated with a photonics chip (which uses light to transfer data)—creating a cohesive final product capable of transmitting information at ultrahigh speed while generating minimal heat.

    Though the two-chip sandwich is unlikely to find its way into your laptop, the new design could influence the future of data centers that manage very high volumes of data communication.

    “Every time you are on a video call, stream a movie, or play an online video game, you’re routing data back and forth through a data center to be processed,” says Caltech graduate student Arian Hashemi Talkhooncheh (MS ’16), lead author of a paper describing the two-chip innovation that was published in the IEEE Journal of Solid-State Circuits [below] on November 3. “There are more than 2,700 data centers in the U.S. and more than 8,000 worldwide, with towers of servers stacked on top of each other to manage the load of thousands of terabytes of data going in and out every second.”

    Just as your laptop heats up on your lap while you use it, the towers of servers in data centers that keep us all connected also heat up as they work, just at a much greater scale. Some data centers are even built underwater to cool whole facility more easily. The more efficient they can be made, the less heat they will generate, and ultimately, the greater the volume of information that they will be able to manage.

    Data processing is done on electronic circuits while data transmission is most efficiently done using photonics. Achieving ultrahigh speed in each domain is very challenging, but engineering the interface between them is even more difficult.

    “There is a continuous demand for increasing the speed of data communication between different chips not only in data centers but also in high-performance computers. As the computing power of the chips scale, the communication speed can become the bottleneck, especially under stringent energy constraints,” says Azita Emami, the Andrew and Peggy Cherng Professor of Electrical Engineering and Medical Engineering; executive officer for electrical engineering; and senior author of the paper.

    To address this challenge, the Caltech/Southampton team designed both an electronics chip and a photonics chip from the ground up and co-optimized them to work together. The process, from the initial idea to the final test in the lab, took four years to complete, with every design choice impacting both chips.

    “We had to optimize the entire system all at the same time, which enabled achieving a superior power efficiency,” Hashemi says. “These two chips are literally made for each other, integrated into one another in three dimensions.”

    The resulting optimized interface between the two chips allows them to transmit 100 gigabits of data per second while producing just 2.4 pico-Joules per transmitted bit. This improves the electro-optical power efficiency of the transmission by a factor of 3.6 compared to the current state-of-the-art. A picojoule is one-trillionth of a Joule, which is defined as the energy released in one second by a current of 1 ampere through a resistance of 1 ohm—or about 0.24 calories.

    “As the world becomes more and more connected, and every device generates more data, it is exciting to show that we can achieve such high data rates while burning a fraction of power compared to the traditional techniques,” says Emami.

    This research was funded by Rockley Photonics and the U.K. Engineering and Physical Sciences Research Council.

    Science paper:
    IEEE Journal of Solid-State Circuits

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    U Southampton campus

    The University of Southampton (UK) is a world-class university built on the quality and diversity of our community. Our staff place a high value on excellence and creativity, supporting independence of thought, and the freedom to challenge existing knowledge and beliefs through critical research and scholarship. Through our education and research we transform people’s lives and change the world for the better.

    Vision 2020 is the basis of our strategy.

    Since publication of the previous University Strategy in 2010 we have achieved much of what we set out to do against a backdrop of a major economic downturn and radical change in higher education in the UK.

    Vision 2020 builds on these foundations, describing our future ambition and priorities. It presents a vision of the University as a confident, growing, outwardly-focused institution that has global impact. It describes a connected institution equally committed to education and research, providing a distinctive educational experience for its students, and confident in its place as a leading international research university, achieving world-wide impact.

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 5:51 pm on November 10, 2022 Permalink | Reply
    Tags: "Keck Observatory's Newest Planet Hunter Puts Its Eye on the Sky", , , , , , Keck Planet Finder instrument on Keck I, KPF detects planets by looking for the periodic motions of their host stars caused by the planets as they orbit around and gravitationally "tug" on the stars-the so called Doppler shift., More than 5000 exoplanets-planets that orbit stars beyond our sun-have been spotted over the last 30 years., State-of-the-art instrument will find and study missing smaller planets., The California Institute of Technology, The Caltech-led Keck Planet Finder (KPF) instrument at W. M. Keck Observatory in Hawaiʻi is now primed and ready to search for and characterize hundreds-ultimately thousands-of exoplanets., The instrument achieved so-called first light on November 9 2022 which means it captured its first data from the sky-in this case from the planet Jupiter., The instrument will determine the compositions of thousands of known planets., The quest for small planets similar to Earth—those most promising in the search for alien life—has been limited due to the miniscule effects that these planets have on their host stars.   

    From The California Institute of Technology: “Keck Observatory’s Newest Planet Hunter Puts Its Eye on the Sky” 

    Caltech Logo

    From The California Institute of Technology

    11.10.22
    Whitney Clavin
    (626) 395‑1944
    wclavin@caltech.edu

    State-of-the-art instrument will find and study missing smaller planets.

    More than 5,000 exoplanets, or planets that orbit stars beyond our sun, have been spotted over the last 30 years, and discoveries from space and ground-based telescopes continue to roll in. The planets come in many sizes and compositions and include everything from molten lava worlds to gas giant planets larger than Jupiter. However, the quest for small planets similar to Earth—those most promising in the search for alien life—has been limited due to the miniscule effects that these planets have on their host stars.

    That will soon change as the Caltech-led Keck Planet Finder (KPF) instrument at W. M. Keck Observatory in Hawaiʻi is now primed and ready to search for and characterize hundreds, and ultimately, thousands of exoplanets, including the missing, smaller ones. The instrument, which uses the “wobble” or radial velocity method of planet hunting, achieved so-called first light on November 9, 2022, which means it captured its first data from the sky, in this case from the planet Jupiter.

    While KPF will routinely observe stars, the KPF team chose to celebrate KPF’s planet-finding capabilities by directly observing Jupiter in our own solar system.

    1
    First light spectrum of the planet Jupiter taken with the Keck Planet Finder. Credit: Guðmundur Stefánsson and the KPF team.

    2
    Spectrum of a star taken with the Keck Planet Finder during its first night of operation. The inset image depicts spectra of the star (Sci) and laser frequency comb calibration source (Cal). Credit: Guðmundur Stefánsson and the KPF team.

    “Seeing KPF’s first astronomical spectrum was a moving experience,” says Andrew Howard, the KPF principal investigator and a professor of astronomy at Caltech. “I’m excited to use the instrument to study the great diversity of exoplanets and to tease apart the mysteries of how they formed and evolved to their present states.”

    “The advent of KPF marks a major and exciting step forward in our ability to advance the quest to eventually find habitable earth-like planets around other stars,” says Hilton Lewis, director of Keck Observatory. “We have been awaiting the arrival of KPF for nearly a decade, and we are thrilled to be able to take our already very successful exoplanet discovery program to the next level.”

    KPF detects planets by looking for the periodic motions of their host stars caused by the planets as they orbit around and gravitationally “tug” on the stars. When the stars move back and forth, or wobble, their light is shifted in the same way that the sound of a siren changes in frequency depending on whether the noise is traveling away from or toward you, a so-called Doppler shift.

    KPF will detect planets by looking for this stellar wobble in the spectra of stars (a spectrum displays the different frequencies of light from a star). The less massive the planet, the smaller the wobble that is produced. The instrument’s state-of-the-art technology means that it can detect planets as small as Earth, and even smaller in some cases. It can also detect Earth-mass planets in the habitable zones of smaller, cooler stars, although it cannot yet see them in the habitable zones of sun-like stars. A habitable zone is the region around a star where temperatures are suited for liquid water, a necessary ingredient for life as we know it.

    “Stars that are cooler than our sun have habitable zones that are located closer to the star,” Howard explains. “Any Earth-like planets in this zone would be huddled close to their stars like it is a campfire. We will continue to tune and refine KPF to detect even fainter wobbles, with the goal of eventually having the sensitivity to detect Earth-mass planets that orbit stars like our sun, the true Earth analogs.”

    In addition to discovering new planets, the instrument will determine the compositions of up to thousands of known planets, and answer mysteries about the surprisingly diverse array of planetary systems identified so far. KPF will also discover nearby planets that make ideal candidates for future portraits by other telescopes, such as the planned Thirty Meter Telescope, which could take direct images of planets orbiting next to their stars.

    “KPF will be much more precise than our current tools, enabling richer science through better measurements of the masses, orbits, and compositions of the smaller planets,” Howard says. “It will also be faster, so we can measure planet masses in much less time than it took before. This means we can survey more planets.”

    Steady as a Rock

    The idea for KPF first came about in 2014 when astronomers were looking for ways to improve planet-hunting instruments that use the radial velocity method. These instruments had already been enormously successful, having uncovered hundreds of exoplanets, but the scientists wanted to push the technology to find smaller and smaller planets. For example, the main planet-hunting instrument at Keck Observatory before KPF, known as the High Resolution Echelle Spectrometer (HIRES), can spot stars moving back and forth, or wobbling, at a speed of 200 centimeters/second.

    KPF, once it is fully up and running by spring 2023, should be able to detect stellar motions of only 30 centimeters/second. That’s significantly slower and translates to smaller planets with a weaker tug on their host stars.

    “We’re measuring a motion that is slower than a human walking. And the stars are light-years away and 100 times larger than the entire Earth,” Howard says.

    The project began at UC Berkeley, where its founding designer Steve Gibson began coming up with ideas for the instrument with Howard and others (Howard moved from Berkeley to the University of Hawaiʻi and then to Caltech in 2016; Gibson became a Caltech affiliate in 2021). A key innovation they developed was to use a special kind of ceramic-glass hybrid material called Zerodur that is used for the base of the instrument and main optical components such as mirrors.

    4
    Andrew Howard with a block of Zerodur. Credit: Caltech.

    6
    Engineers guide KPF’s Zerodur bench to a support in the basement at Keck Observatory. Credit: W. M. Keck Observatory.

    Made by the company Schott AG, Zerodur is used in semiconductor manufacturing as well as cookware and telescope mirrors, including those of Keck Observatory. The amber-hued material is highly thermally stable; basically, if you heat or cool the material, it only slightly expands or contracts (it has about 10,000 times less thermal movement than steel).

    This thermal stability is key to KPF because any movement in the instrument can lead to false signals that appear to be Doppler shifts from stars. By reducing thermal movements, the team can make KPF even more precise.

    “This is the first spectrometer to integrate Zerodur into its design,” Howard says. “The material, which comes in giant slabs, is fragile and hard to work with, but it is what makes KPF so sensitive to smaller planets.”

    “Light bounces between mirrors inside the instrument,” explains Ryan Rubenzahl (MS ’21), a Caltech graduate student working on KPF in Howard’s group. “If the base of the spectrograph expands, then the distance between the mirrors changes and this leads to light landing in the wrong place. It may look like stellar light has Doppler shifted because of orbiting planets, but in fact the instrument itself has shifted.”

    KPF uses other innovations to limit spurious signals as well. For instance, the team developed specialized fiber-optic cables with cross sections shaped like octagons instead of circles. The octagon shape evens out the flow of light in the cables, reducing the chance of false signals that look like stellar Doppler shifts. At Keck Observatory, fiber-optic cables carry light from the Keck I telescope to the KPF instrument, which resides in a basement below the observatory.

    “KPF was designed from the ground up to track the spectral fingerprints of stars to better than 1 part per billion precision,” says Sam Halverson, the KPF instrument scientist and an astronomer and optical engineer at Jet Propulsion Laboratory (JPL), which is managed by Caltech for NASA. “This scale of measurement represents a significant technological challenge, and required that every layer of the KPF system, from the all-Zerodur spectrometer, to the fiber delivery system, to the data analysis software, be carefully optimized to maximize performance.”

    Another device that will improve the scientists’ understanding of false signals is called the Solar Calibrator, or SoCal for short. The small device sits in an enclosure on the roof of Keck Observatory and tracks our sun. Because a star’s turbulence and sunspots can also give off anomalous Doppler shift signals, the KPF team is tracking the sun to better understand the noise and correct for it in their data.

    “The sun has answers,” says Rubenzahl, whose PhD thesis will focus in part on SoCal. “It’s the only star in the universe for which we know every single one of its orbiting planets, and we know where every sunspot is and what the sun’s magnetic field is doing at all times. So if we track the sun with KPF, we can subtract the planet signals and look at what’s left to study how sunspots and other features of the sun create false Doppler shifts.”

    Planets Galore

    After KPF finishes its commissioning phase in the spring, it will be ready to hunt for planets. One of the projects that Howard is most excited about is to search for the so-called ultra-short period planets. These are rocky planets about the size of Earth that whip around their stars in less than a day.

    “The planets are blowtorched by their stars,” Howard says. “Investigating these unusual planets will demonstrate that KPF can see smaller planets on the scientific frontier. This project will allow KPF to flex its muscles and show what it can do.”

    Howard and his colleagues would also like to search the 50 closest to Earth for missing smaller planets. “We want to take a census of our nearest stars and find the smaller planets we haven’t been able to see until now. We want to know the names, addresses, and characteristics of planets that are neighbors of our Earth.”

    Other planned KPF projects include a study of planets already discovered by NASA’s Kepler Space Telescope, which operated from 2009 to 2018.

    Kepler used the transit method of planet hunting, in which planets are detected as they pass in front of their stars and block the light.

    Whereas Kepler measures the actual size of planets, KPF probes planet masses (the more massive a planet, the larger the wobble detected). By combining the datasets, researchers can learn about the compositions of around 1,000 of the Kepler planets.

    KPF will also be ideally suited to study planets with unusual orbits. “We are really interested in learning about planets with weird orbits, such as those that go around the poles of the star rather than the equator or even stars that have backward orbits,” Rubenzahl says.

    The researchers say that the power of KPF lies not just in its advanced technology but in its home at the W. M. Keck Observatory, whose twin telescopes atop Mauna Kea are among the largest in the world with diameters of 10 meters each. The size of the Keck Observatory telescopes lets KPF study fainter stars and observe them more quickly.

    “Achieving first light is a momentous occasion for the dozens of KPF scientists, engineers, and software specialists who have worked for years to develop a complete, cutting-edge exoplanet discovery system,” Halverson says.

    The design and construction of KPF has been supported by the National Science Foundation, Heising-Simons Foundation, W. M. Keck Foundation, Simons Foundation; Mt. Cuba Foundation, JPL, private donors, Keck Observatory; Caltech; University of California; and University of Hawaiʻi.

    See the full article here .

    See also the article from Keck Observatory here.


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 10:00 am on October 14, 2022 Permalink | Reply
    Tags: "DOM": dissolved organic matter, "New insights into the ocean's oldest carbon", , , , The California Institute of Technology   

    From The California Institute of Technology: “New insights into the ocean’s oldest carbon” 

    Caltech Logo

    From The California Institute of Technology

    10.13.22
    Robert Perkins
    (626) 395‑1862
    rperkins@caltech.edu

    1
    Using a newly developed technique, researchers have ruled out a potential source of ancient dissolved organic matter (DOM) in the world’s oceans.

    “DOM”-dissolved organic matter is organic material—mostly carbon, but also some nitrogen, sulfur, oxygen, and other elements—that is smaller than approximately 0.7 micrometers in size (tinier than a bacterium) and is dissolved in seawater. Because DOM is a major reservoir of carbon, this finding has implications for the sequestration of carbon in the deep ocean (generally defined as the area where light cannot penetrate, a depth of around 200 meters). DOM can exist in the deep ocean for hundreds to thousands of years, though no one is sure why it persists for so long.

    The new research suggests that the accumulation of DOM in the deep ocean occurs with negligible input from organic sulfur compounds found in ocean sediments, and thus rejects one leading hypotheses for why it persists for so long.

    “Our paper helped address a lingering question in carbon sequestration, rejecting a theory of where some old carbon was coming from,” says Alexandra Phillips (PhD ’21), lead author of a paper on the research that was published in PNAS [below] on October 7. Phillips is a postdoctoral scholar at UC Santa Barbara, but conducted the research while a graduate student at Caltech with Alex Sessions, professor of geobiology.

    The ocean has about as much carbon in the form of DOM as there is carbon dioxide in the atmosphere. DOM is thought to be important for climate regulation because it essentially traps carbon for extended periods.

    Phillips tested the hypothesis that extremely long-lived DOM exists due to reactions with hydrogen sulfide in porewaters (the water that flows through sediments on the ocean floor), creating molecules that then leech from sediments into the ocean. Such reactions are known to make molecules more resistant to microbial degradation, and scientists have previously linked the creation of “sulfurized” organic matter in sediments to cooling events in Earth’s history.

    Phillips, Sessions, and their colleagues at Caltech, Scripps Institution of Oceanography, and the University of Oldenburg in Germany, used sulfur isotopes to test if these sulfurization reactions were also responsible for a significant portion of the deep ocean’s old carbon.

    Phillips spent her time in graduate school at Caltech improving techniques for sulfur isotope measurement. The abundance of stable isotopes in a given sample often yields clues about its source. For example, sulfur most commonly occurs in two forms: sulfur-32 and sulfur-34 isotopes (with the heavier sulfur-34 isotope containing two more neutrons than sulfur-32). Analyzing the relative abundance of each isotope in a sample can tell you a bit about the sample’s origins. For example, microbes in areas without oxygen use sulfate (a molecule of sulfur and oxygen) for energy and create sulfide (a negatively charged sulfur ion) as a byproduct. This reaction is faster with the lighter sulfur-32 isotope, which in turn causes the resulting sulfide to have more sulfur-32.

    However, for sulfur, the large sample sizes needed to accurately measure the isotope ratio made it an impractical way to study DOM. That is, until Phillips and her colleagues developed a way to analyze sulfur isotopes at very low levels, which in turn decreases the samples sizes needed from about 10 milligrams of DOM (yielding about 100 micrograms of sulfur) to about 0.1 milligrams of DOM (yielding about 1 microgram of sulfur).

    In practical terms, it is the difference between filtering only 10 liters of seawater per sample instead of 1,000 liters.

    “This is a classic example of how fundamental research into improving measurement techniques can pay dividends in terms of new science,” Sessions says. “With Alex’s thesis work helping to lower detection limits for organic sulfur isotopes by two orders of magnitude, the analysis of marine DOM suddenly became quite practical.”

    Their measurement relied on burning small amounts of isolated DOM samples and precisely analyzing the resulting gas mixture using mass spectrometry. This allowed the team to measure the isotope ratios of each gas that emerges in fine detail. The Sessions Lab at Caltech has been refining similar techniques for years—but this was the first field test of these new sulfur isotope methods.

    “It was like we were a hammer searching for nails,” Phillips says. “We spent time developing this awesome method and were eager to apply it to answer a big question. This method really opened the floodgates for possible measurements of organic sulfur.”

    The team found sulfur isotope signals that did not match a sedimentary source. The samples, collected from deep in the Pacific and Atlantic oceans, had much more sulfur-34 than would be expected if the material originated from sulfurized organic matter. The researchers also noted that as the relative abundance of sulfur-34 decreased in their samples, the samples also showed an overall loss of sulfur relative to carbon. This further disproved the hypothesis that sulfurized organic matter was the missing source of the ocean’s oldest dissolved carbon.

    Instead, the sulfur isotope ratios were nearly identical to those found in phytoplankton, the microscopic photosynthesizing organisms that comprise the base of the marine food web. The findings offer direct evidence that phytoplankton is the origin of the sulfur, and indirect evidence for the origin of DOM in general. However, it should be noted that sulfur-containing compounds comprise less than 10 percent of typical DOM.

    “Most people who study sulfur use it just as a window into carbon cycling, but I think this result shows that biology is also the starting point for sulfur,” Phillips says. “Marine organic sulfur is a lot more dynamic than we were expecting.”

    Caltech coauthors include Fenfang Wu, laboratory manager; Frank J. Pavia, Stanback Postdoctoral Scholar Research Associate in Environmental Science and Engineering; and former graduate student Preston C. Kemeny (MS ’18, PhD ’22), who is now a postdoctoral fellow at the University of Chicago. Other coauthors include Margot E. White and Lihini I. Aluwihare of Scripps Institution of Oceanography in San Diego; Audrey C. Ma of USC; and Michael Seidel and Thorsten Dittmar of the University of Oldenburg in Germany. Funding for this work came from the National Science Foundation, the German Research Foundation (DFG), and the Fannie and John Hertz Foundation.

    Science paper:
    PNAS

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 3:32 pm on October 11, 2022 Permalink | Reply
    Tags: "Graphene Boosts Flexible and Wearable Electronics", , At 200 times stronger than steel graphene has been hailed as a super material of the future since its discovery in 2004., Gold coated in graphene could better withstand the sweat of a person's body., Graphene can greatly improve electrical circuits required for wearable and flexible electronics., Graphene is an incredibly strong electrical and thermal conductor making it a perfect ingredient to enhance semiconductor chips found in many electrical devices., Graphene slows down the rate at which the gold is corroded., Graphene-coated copper structures could be folded 200000 times without damage., , The California Institute of Technology, The scientists figured out a better and more cost-effective and environmentally friendly way to grow graphene on materials.   

    From The California Institute of Technology: “Graphene Boosts Flexible and Wearable Electronics” 

    Caltech Logo

    From The California Institute of Technology

    10.11.22

    Whitney Clavin
    (626) 395‑1944
    wclavin@caltech.edu

    1
    Credit: Nai-Chang Yeh and Chen-Hsuan (Steve) Lu.

    At 200 times stronger than steel, graphene has been hailed as a super material of the future since its discovery in 2004. The ultrathin carbon material is an incredibly strong electrical and thermal conductor making it a perfect ingredient to enhance semiconductor chips found in many electrical devices.

    But while graphene-based research has been fast-tracked, the nanomaterial has hit roadblocks: in particular, manufacturers have not been able to create large, industrially relevant amounts of the material. New research from the laboratory of Nai-Chang Yeh, the Thomas W. Hogan Professor of Physics, is reinvigorating the graphene craze.

    In 2015, Yeh and her colleagues, including senior research scientist David Boyd, announced that they had figured out a better, more cost-effective, and environmentally friendly way to grow graphene on materials. Called plasma-enhanced chemical vapor deposition, the method can be used to grow high-quality graphene sheets, only one atom thick, at room temperature in about 15 minutes. This is in contrast to other methods that require much higher temperatures, harsh chemicals, and take several hours to complete.

    In two new studies, the researchers demonstrate that graphene can greatly improve electrical circuits required for wearable and flexible electronics such as smart health patches, bendable smartphones, helmets, large folding display screens, and more.

    In one study, published in ACS Applied Materials & Interfaces [below], the researchers grew graphene directly onto thin two-dimensional copper lines commonly used in electronics. The results showed that the graphene not only improved the lines’ conducting properties but also protected the copper-based structures from usual wear and tear. For instance, they showed that graphene-coated copper structures could be folded 200,000 times without damage, as compared to the original copper structures, which started cracking after 20,000 folds. The results demonstrate that graphene can help create flexible electronics with longer lifetimes.

    The second study, published in ACS Applied Nano Materials [below], demonstrated that gold coated in graphene could better withstand the sweat of a person’s body, and thus would make better implantable biosensors. Gold is a common ingredient used in the development of implantable biosensors, or smart patches—nanoscale devices for monitoring various health conditions. Graphene slows down the rate at which the gold is corroded.

    The two studies, in addition to a third study in ACS Applied Materials & Interfaces [below] showing that graphene can protect electrical circuits produced via inkjet printers, used the Yeh group’s unique method for growing graphene.

    “Flexible and wearable electronics can be made of soft materials like polymers that can’t sustain high temperatures,” says Chen-Hsuan (Steve) Lu (MS ’20), a Caltech graduate student and lead author of the three studies. “Our method allows us to grow graphene directly on the substrates at a low temperature, preventing any damage to sensitive materials.”

    Yeh adds that their graphene-growth method, which can be scaled up for industrial needs, is compatible with a host of other applications in addition to flexible and wearable electronics.

    “Our method is highly compatible with all kinds of substrates, ranging from tiny, nanostructure metals, to semiconducting materials, to even plastics. Because we don’t require high temperatures, this method can be used on different substrates for many applications,” she says.

    Pink Plasma

    The group’s method for growing sheets of graphene is performed in their basement laboratory. A ray of plasma, which glows pink, is used to activate a gas of hydrogen and methane molecules and break them down into smaller fragments. The sample, such as a two-dimensional copper line, is then immersed in the plasma, and the carbon from the gas gets deposited onto the surface in thin sheets that are one atom thick. The final surface with the graphene will appear shinier.

    2
    A ray of plasma, which glows pink, is used to activate a gas of hydrogen and methane molecules and break them down into smaller fragments. The sample to be coated, such as a two-dimensional copper line, is then immersed in the plasma, and carbon from the gas gets deposited onto the surface as thin sheets of graphene. Credit: Caltech.

    “Because the sample is immersed in the plasma without the need of active heating up to about 1,000 degrees Celsius by a hot furnace, which is the case with other methods, much lower-temperature growth becomes feasible,” Lu says.

    For the study that tested graphene’s ability to enhance the flexibility of electronics, the team partnered with the Materials and Chemical Research Laboratories at the Taiwanese organization called Industrial Technology Research Institute (ITRI). The Caltech team created graphene-coated copper structures that mimic what would be used in flexible electronics and then had their partners at ITRI fold them; the company has the equipment necessary to repeatedly fold the structures hundreds of thousands of times. “I tried and was not able to stand there and fold the materials this long myself,” Lu jokes.

    “The ITRI has been playing an important role in bridging laboratory research to industrial productions in Taiwan over decades. The most well-known example among many spin-off companies from ITRI is the Taiwan Semiconductor Manufacturing Company (TSMC), currently the world’s largest and leading semiconductor foundry,” says Yeh, who recently traveled to Taiwan to visit her collaborators at ITRI (both Yeh and Lu are originally from Taiwan).

    In this same study, the researchers also showed that graphene could improve the copper structures’ chemical stability and electrical conductivity, in addition to its structural flexibility. “We put just two atomic layers of graphene on top of these thin copper lines and saw that they were beautifully unchanged after several months,” Yeh says.

    The second study tested whether graphene could protect the durability of gold structures used in implantable biosensors. The researchers grew graphene on gold and then exposed the material to saline solutions that mimic sweat. The results showed that the graphene-coated structure remained intact under conditions equivalent to approximately one month at normal human body temperatures, much longer than what is possible with gold alone.

    “I wasn’t aware of graphene’s full potential when I first started working with it,” Lu says. “But then I realized how it can be used in tandem with other materials for so many applications. My roommate [co-author Kuang Ming (Allen) Shang] and I were having a boba tea when we realized we could test whether graphene might protect gold from the corrosive effects of sweat.” (Lu says that his favorite Taiwanese drink, boba tea, helps to inspire him with new ideas.)

    What is Next for Graphene?

    While graphene has taken more time to make its way into electronics than first anticipated, its future appears bright. In addition to the use of graphene in wearable and flexible electronics, Yeh is examining graphene’s potential in everything from energy research and optical communications to environmentally friendly batteries and more.

    Graphene is also key, she says, to the growing field of nanoelectronics, which aims to create smaller versions of the electronics widely used today. Graphene can be used in combination with silicon to shrink devices down to smaller and smaller sizes.

    “Graphene, when combined with other materials, can make our nanotechnologies smaller and faster. It leads to lower heat dissipation and energy consumption. In our lab, we use graphene for so many things. It’s exciting,” she says.

    Science papers:
    Nature Communications 2015
    ACS Applied Materials & Interfaces
    ACS Applied Nano Materials
    ACS Applied Materials & Interfaces

    See the science papers for detailed material with images.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 10:34 am on October 9, 2022 Permalink | Reply
    Tags: "Diff-CUP": differentially enhanced compressed ultrafast photography, "High-speed camera captures signals traveling through nerve cells", , , , The California Institute of Technology   

    From The California Institute of Technology: “High-speed camera captures signals traveling through nerve cells” 

    Caltech Logo

    From The California Institute of Technology

    10.6.22
    Emily Velasco
    (626) 372‑0067
    evelasco@caltech.edu

    1
    Caltech scientists have developed a new ultrafast camera that can record footage of signal impulses as they travel through nerve cells. Credit: Caltech.

    Reach out right now and touch anything around you. Whether it was a key on your keyboard, the wood of your desk, or the fur of your dog, you felt it the instant your finger contacted it.

    Or did you?

    In actuality, it does take a bit of time for your brain to register the sensation from your fingertip, but it does still happen pretty darn fast, with the touch signal traveling through your nerves at over 100 miles per hour. Some nerve signals are even faster, approaching speeds of 300 miles per hour.

    Now, scientists at Caltech have developed a new ultrafast camera that can record footage of these impulses as they travel through nerve cells. The camera can also capture video of other ultrafast phenomena, like the propagation of electromagnetic pulses in electronics.

    The camera technology, known as differentially enhanced compressed ultrafast photography (Diff-CUP), was developed in the lab of Lihong Wang, Bren Professor of Medical Engineering and Electrical Engineering, Andrew and Peggy Cherng Medical Engineering Leadership Chair, and executive officer for medical engineering.

    Diff-CUP operates similarly to Wang’s other CUP systems, which have been shown capable of recording video at 70 trillion frames per second and capturing images of laser pulses as they travel at the speed of light.

    Diff-CUP takes the same high-speed camera technology found in the other CUP systems and combines it with a device called a Mach–Zehnder interferometer. The interferometer images objects and materials by first splitting a beam of laser light in two, passing only one of the split beams through an object, and then recombining the beams. Because light waves are affected by the objects they pass through, with different materials affecting them in varying ways, the beam passing through the material being imaged will have its waves set out of sync with the waves of the other beam. When the beams are recombined, the out-of-sync waves interfere with each other (hence “interferometer”) in patterns that reveal information about the object being imaged.

    Though you cannot see an electrical pulse traveling through a nerve cell with your own eyes, or even a conventional light microscope, this type of interferometry can detect it. (Incidentally, this same basic technique is used by LIGO to detect gravitational waves.) So, the Mach–Zehnder interferometer allows the imaging of these pulses, and the CUP camera captures the images at incredibly high frame rates.

    2
    Electrical pulses can be seen traveling at different speeds through different neurons. Credit: Caltech.

    “Seeing nerve signals is fundamental to our scientific understanding but has not yet been achieved owing to the lack of speed and sensitivity provided by existing imaging methods,” Wang says.

    Wang’s research team also captured photos of the propagation of electromagnetic pulses (EMP), which, in some materials, can travel at nearly the speed of light. In this case, they passed the electromagnetic pulses through a crystal of lithium niobate, a salt that has unique optical and electrical properties. Despite the extremely high speed at which an EMP passes through this material, the camera was able to clearly image it.

    “Imaging propagating signals in peripheral nerves is the first step,” Wang says. “It’d be important to image live traffic in a central nervous system, which would shed light on how the brain works.”

    The paper describing their findings appeared in the journal Nature Communications [below] on September 6. Co-authors are Yide Zhang, postdoctoral scholar research associate in medical engineering; Binglin Shen, visitor from Shenzhen University; Tong Wu, visitor from Nanjing University of Aeronautics and Astronautics; Jerry Zhao, former graduate student of the USC–Caltech MD-PhD program; Joseph C. Jing, formerly of Caltech and currently at Cepton; Peng Wang, senior postdoctoral scholar research associate in medical engineering; Kanomi Sasaki-Capela, former research technician at Caltech; William G. Dunphy, Grace C. Steele Professor of Biology; David Garrett, graduate student in medical engineering; Konstantin Maslov, former staff scientist at Caltech; and Weiwei Wang of University of Texas Southwestern Medical Center.

    Funding for the research was provided by the National Institutes of Health.

    Science paper:
    Nature Communications
    See the science paper for detailed material with images

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The California Institute of Technology is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration ‘s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute as well as National Aeronautics and Space Administration. According to a 2015 Pomona College study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration; National Science Foundation; Department of Health and Human Services; Department of Defense, and Department of Energy.

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech , The California Institute of Technology also operates the Caltech Palomar Observatory; the Owens Valley Radio Observatory;the Caltech Submillimeter Observatory; the W. M. Keck Observatory at the Mauna Kea Observatory; the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Hanford, Washington; and Kerckhoff Marine Laboratory in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center, part of the Infrared Processing and Analysis Center located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
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