Natural Sciences
Showing 121-140 of 382 Results
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Peter Graham
Wells Family Director of the Stanford Institute for Theoretical Physics and Dr. William S. & Carol A. Davies Professor of Physics
Current Research and Scholarly InterestsWhat physics lies beyond the Standard Model and how can we discover it?
Professor Graham is broadly interested in theoretical physics beyond the Standard Model which often involves cosmology, astrophysics, general relativity, and even atomic physics. The Standard Model leaves many questions unanswered including the nature of dark matter and the origins of the weak scale, the cosmological constant, and the fundamental fermion masses. These clues are a guide to building new theories beyond the Standard Model. He recently proposed a new solution to the hierarchy problem which uses dynamical relaxation in the early universe instead of new physics at the weak scale.
Professor Graham is also interested in inventing novel experiments to discover such new physics, frequently using techniques from astrophysics, condensed matter, and atomic physics. He is a proposer and co-PI of the Cosmic Axion Spin Precession Experiment (CASPEr) and the DM Radio experiment. CASPEr uses nuclear magnetic resonance techniques to search for axion dark matter. DM Radio uses high precision magnetometry and electromagnetic resonators to search for hidden photon and axion dark matter. He has also proposed techniques for gravitational wave detection using atom interferometry.
Current areas of focus:
Theory beyond the Standard Model
Dark matter models and detection
Novel experimental proposals for discovering new physics such as axions and gravitational waves
Understanding results from experiments ranging from the LHC to early universe cosmology -
Giorgio Gratta
Ray Lyman Wilbur Professor
BioGiorgio Gratta is a Professor of Physics at Stanford university. Gratta is an experimentalist, with research interests in the broad area of the physics of fundamental particles and their interactions. While his career started with experiments at particle colliders, since at Stanford Gratta has tackled the study of neutrinos and gravity at the shortest distances.
With two landmark experiments using neutrinos produced by nuclear reactors, Gratta and collaborators investigated the phenomenon of neutrino flavor mixing, in one case reporting the first evidence for neutrino oscillations using artificial neutrinos. This established the finite nature of neutrino masses. The same experiment was also first to detect neutrinos from the interior of our planet, providing a new tool for the Earth sciences.
As a natural evolution from the discovery of neutrino oscillations, Gratta has led the development of liquid Xenon detectors in the search for the neutrinoless double beta decay, an exotic nuclear decay that, if observed, would change our understanding of the quantum nature of neutrinos and help explaining the asymmetry between matter and antimatter in the universe. Gratta is currently the scientific leader of one of the three very large experiments on the subject, world-wide.
In a rather different area of research, Gratta’s group is studying new long range interactions (or an anomalous behavior of gravity) at distances below 50 micrometers. This is achieved with an array of different techniques, from optical levitation of microscopic particles in vacuum, to the use of Mössbauer spectroscopy and, most recently, neutron scattering on nanostructured materials. -
Arthur Grossman
Visiting Professor (By courtesy), Biology
Professor (By Courtesy), BiologyCurrent Research and Scholarly InterestsHow photosynthetic organisms perceive and respond to their environment
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Elizabeth Hadly
Paul S. and Billie Achilles Professor of Environmental Biology and Professor of Earth System Science, Emerita
Current Research and Scholarly InterestsElizabeth Hadly and her lab probe how perturbations such as climatic change and human modification of the environment influence the evolution and ecology of animals.
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Philip C. Hanawalt
Dr. Morris Herzstein Professor in Biology, Emeritus
Current Research and Scholarly InterestsMy current interest includes two principal areas:
1. The molecular basis for diseases in which the pathway of transcription-coupled DNA repair is defective, including Cockyne syndrome (CS) and UV-sensitive syndrome (UVSS). Patients are severely sensitive to sunlight but get no cancers. See Hanawalt & Spivak, 2008, for review.
2. Transcription arrest by guanine-rich DNA sequences and non-canonical secondary structures. Transcription collisions with replication forks. -
Trevor Hastie
John A. Overdeck Professor, Professor of Statistics and of Biomedical Data Sciences, Emeritus
Current Research and Scholarly InterestsFlexible statistical modeling for prediction and representation of data arising in biology, medicine, science or industry. Statistical and machine learning tools have gained importance over the years. Part of Hastie's work has been to bridge the gap between traditional statistical methodology and the achievements made in machine learning.
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Patrick Hayden
Stanford Professor of Quantum Physics
BioProfessor Hayden is a leader in the exciting new field of quantum information science. He has contributed greatly to our understanding of the absolute limits that quantum mechanics places on information processing, and how to exploit quantum effects for computing and other aspects of communication. He has also made some key insights on the relationship between black holes and information theory.
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Tony Heinz
Director, Edward L. Ginzton Laboratory, Professor of Applied Physics, of Photon Science, and, by courtesy, of Electrical Engineering
Current Research and Scholarly InterestsElectronic properties and dynamics of nanoscale materials, ultrafast lasers and spectroscopy.
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H. Craig Heller
Lorry I. Lokey/Business Wire Professor
Current Research and Scholarly InterestsNeurobiology of sleep, circadian rhythms, regulation of body temperature, mammalian hibernation, and human exercise physiology. Currently applying background in sleep and circadian neurobiology the understanding and correcting the learning disability of Down Syndrome.
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Luis Hernandez-Nunez
Assistant Professor of Biology
BioLuis Hernandez-Nunez is a tenure-track professor of biology, a Warren Alpert Distinguished Scholar, a Branco Weiss faculty fellow, and a Burroughs Wellcome Career Award faculty fellow at Stanford University, where he leads the Hernandez-Nunez Lab. Luis’ research focuses on the circuit mechanisms underlying heart-brain interactions and on organismal circuits that implement multiorgan coordination and feedback control. Luis did his postdoctoral training with Florian Engert supported by an LSRF fellowship. Luis obtained his Ph.D. in Systems, Synthetic, and Quantitative Biology from Harvard in 2020. He conducted his doctoral research in Aravinthan Samuel’s lab, where he identified molecules, cells, and circuits that mediate thermal homeostasis in larval Drosophila. Before graduate school, Luis was an undergraduate and then a postbac researcher at Thierry Emonet’s lab at Yale University. Before moving to the U.S., Luis studied mechatronics engineering at the National University of Engineering in Peru.
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Lambertus Hesselink
Professor of Electrical Engineering and, by courtesy of Applied Physics
BioHesselink's research encompasses nano-photonics, ultra high density optical data storage, nonlinear optics, optical super-resolution, materials science, three-dimensional image processing and graphics, and Internet technologies.
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Keith Hodgson
David Mulvane Ehrsam and Edward Curtis Franklin Professor of Chemistry and Professor of Photon Science
BioCombining inorganic, biophysical and structural chemistry, Professor Keith Hodgson investigates how structure at molecular and macromolecular levels relates to function. Studies in the Hodgson lab have pioneered the use of synchrotron x-radiation to probe the electronic and structural environment of biomolecules. Recent efforts focus on the applications of x-ray diffraction, scattering and absorption spectroscopy to examine metalloproteins that are important in Earth’s biosphere, such as those that convert nitrogen to ammonia or methane to methanol.
Keith O. Hodgson was born in Virginia in 1947. He studied chemistry at the University of Virginia (B.S. 1969) and University of California, Berkeley (Ph.D. 1972), with a postdoctoral year at the ETH in Zurich. He joined the Stanford Chemistry Department faculty in 1973, starting up a program of fundamental research into the use of x-rays to study chemical and biological structure that made use of the unique capabilities of the Stanford Synchrotron Radiation Lightsource (SSRL). His lab carried out pioneering x-ray absorption and x-ray crystallographic studies of proteins, laying the foundation for a new field now in broad use worldwide. In the early eighties, he began development of one of the world's first synchrotron-based structural molecular biology research and user programs, centered at SSRL. He served as SSRL Director from 1998 to 2005, and SLAC National Accelerator Laboratory (SLAC) Deputy Director (2005-2007) and Associate Laboratory Director for Photon Science (2007-2011).
Today the Hodgson research group investigates how molecular structure at different organizational levels relates to biological and chemical function, using a variety of x-ray absorption, diffraction and scattering techniques. Typical of these molecular structural studies are investigations of metal ions as active sites of biomolecules. His research group develops and utilizes techniques such as x-ray absorption and emission spectroscopy (XAS and XES) to study the electronic and metrical details of a given metal ion in the biomolecule under a variety of natural conditions.
A major area of focus over many years, the active site of the enzyme nitrogenase is responsible for conversion of atmospheric di-nitrogen to ammonia. Using XAS studies at the S, Fe and Mo edge, the Hodgson group has worked to understand the electronic structure as a function of redox in this cluster. They have developed new methods to study long distances in the cluster within and outside the protein. Studies are ongoing to learn how this cluster functions during catalysis and interacts with substrates and inhibitors. Other components of the protein are also under active study.
Additional projects include the study of iron in dioxygen activation and oxidation within the binuclear iron-containing enzyme methane monooxygenase and in cytochrome oxidase. Lab members are also investigating the role of copper in electron transport and in dioxygen activation. Other studies include the electronic structure of iron-sulfur clusters in models and enzymes.
The research group is also focusing on using the next generation of x-ray light sources, the free electron laser. Such a light source, called the LCLS, is also located at SLAC. They are also developing new approaches using x-ray free electron laser radiation to image noncrystalline biomolecules and study chemical reactivity on ultrafast time scales.
