Physics
Showing 21-30 of 80 Results
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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. -
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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Leo Hollberg
Professor (Research) of Physics and of Geophysics
BioHow can we make optimal use of quantum systems (atoms, lasers, and electronics) to test fundamental physics principles, enable precision measurements of space-time and when feasible, develop useful devices, sensors, and instruments?
Professor Hollberg’s research objectives include high precision tests of fundamental physics as well as applications of laser physics and technology. This experimental program in laser/atomic physics focuses on high-resolution spectroscopy of laser-cooled and -trapped atoms, non-linear optical coherence effects in atoms, optical frequency combs, optical/microwave atomic clocks, and high sensitivity trace gas detection. Frequently this involves the study of laser noise and methods to circumvent measurement limitations, up to, and beyond, quantum limited optical detection. Technologies and tools utilized include frequency-stabilized lasers and chip-scale atomic devices. Based in the Hansen Experimental Physics Laboratory (HEPL), this research program has strong, synergistic, collaborative connections to the Stanford Center on Position Navigation and Time (SCPNT). Research directions are inspired by experience that deeper understanding of fundamental science is critical and vital in addressing real-world problems, for example in the environment, energy, and navigation. Amazing new technologies and devices enable experiments that test fundamental principles with high precision and sometimes lead to the development of better instruments and sensors. Ultrasensitive optical detection of atoms, monitoring of trace gases, isotopes, and chemicals can impact many fields. Results from well-designed experiments teach us about the “realities” of nature, guide and inform, occasionally produce new discoveries, frequently surprise, and almost always generate new questions and perspectives. -
Kent Irwin
Director, Hansen Experimental Physics Laboratory (HEPL), Professor of Physics, of Particle Physics and Astrophysics and of Photon Science
BioIrwin Group web page:
https://irwinlab.stanford.edu/ -
Shamit Kachru
Professor of Physics and Director, Stanford Institute for Theoretical Physics, Emeritus
Current Research and Scholarly InterestsMy current research is focused in three directions:
— Mathematical aspects of string theory (with a focus on BPS state counts, black holes, and moonshine)
— Quantum field theory approaches to condensed matter physics (with a focus on physics of non-Fermi liquids)
— Theoretical biology, with a focus on evolution and ecology -
Renata Kallosh
Stanford W. Ascherman, MD Professor, Emerita
BioWhat is the mathematical structure of supergravity/string theory and its relation to cosmology?
Professor Kallosh works on the general structure of supergravity and string theory and their applications to cosmology. Her main interests are related to the models early universe inflation and dark energy in string theory. She develops string theory models explaining the origin of the universe and its current acceleration. With her collaborators, she has recently constructed de Sitter supergravity, which is most suitable for studies of inflation and dark energy and spontaneously broken supersymmetry.
She is analyzing possible consequences of the expected new data from current and future cosmological observations, including LiteBIRD satellite CMB data. These results may affect the relationship between superstring theory and supergravity, and the real world. Professor Kallosh works, in particular, on future tests of string theory by CMB data and effective supergravity models with flexible amplitude of gravitational waves produced during inflation.
