Natural Sciences
Showing 501-600 of 1,949 Results
-
David Goldhaber-Gordon
TG Wijaya Professor of Physics and Professor, by courtesy, of Applied Physics
Current Research and Scholarly InterestsHow do electrons organize themselves on the nanoscale?
We know that electrons are charged particles, and hence repel each other; yet in common metals like copper billions of electrons have plenty of room to maneuver and seem to move independently, taking no notice of each other. Professor Goldhaber-Gordon studies how electrons behave when they are instead confined to tiny structures, such as wires only tens of atoms wide. When constrained this way, electrons cannot easily avoid each other, and interactions strongly affect their organization and flow. The Goldhaber-Gordon group uses advanced fabrication techniques to confine electrons to semiconductor nanostructures, to extend our understanding of quantum mechanics to interacting particles, and to provide the basic science that will shape possible designs for future transistors and energy conversion technologies. The Goldhaber-Gordon group makes measurements using cryogenics, precision electrical measurements, and novel scanning probe techniques that allow direct spatial mapping of electron organization and flow. For some of their measurements of exotic quantum states, they cool electrons to a fiftieth of a degree above absolute zero, the world record for electrons in semiconductor nanostructures. -
Benjamin Good
Assistant Professor of Applied Physics and, by courtesy, of Biology
BioBenjamin Good is a theoretical biophysicist with a background in experimental evolution and population genetics. He is interested in the short-term evolutionary dynamics that emerge in rapidly evolving microbial populations like the gut microbiome. Technological advances are revolutionizing our ability to peer into these evolving ecosystems, providing us with an increasingly detailed catalog of their component species, genes, and pathways. Yet a vast gap still remains in understanding the population-level processes that control their emergent structure and function. Our group uses tools from statistical physics, population genetics, and computational biology to understand how microscopic growth processes and genome dynamics at the single cell level give rise to the collective behaviors that can be observed at the population level. Projects range from basic theoretical investigations of non-equilibrium processes in microbial evolution and ecology, to the development of new computational tools for measuring these processes in situ in both natural and experimental microbial communities. Through these specific examples, we seek to uncover unifying theoretical principles that could help us understand, forecast, and eventually control the ecological and evolutionary dynamics that take place in these diverse scenarios.
-
Deborah M Gordon
Paul S. and Billie Achilles Professor of Environmental Biology
Current Research and Scholarly InterestsProfessor Deborah M Gordon studies the evolutionary ecology of collective behavior. Ant colonies operate without central control, using local interactions to regulate colony behavior.
-
Or Gozani
Dr. Morris Herzstein Professor
Current Research and Scholarly InterestsWe study the molecular mechanisms by which chromatin-signaling networks effect nuclear and epigenetic programs, and how dysregulation of these pathways leads to disease. Our work centers on the biology of lysine methylation, a principal chromatin-regulatory mechanism that directs epigenetic processes. We study how lysine methylation events are generated, sensed, and transduced, and how these chemical marks integrate with other nuclear signaling systems to govern diverse cellular functions.
-
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
-
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.
-
Eunice Han
Student Svcs Offcr 1, Physics
Current Role at StanfordStudent Services Officer 1
-
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.
