Department of Physics

Faculty Description


Contact
  • Office Location:  
    Physics Professor: MHA 5641
    Phone: 858-534-6329
    Fax: 858-534-0173
    MC 0424

    CASS Director: SERF 409
    Phone: 858-534-9085
    Fax: 858-534-0177

  • Email:  gfuller@physics.ucsd.edu
  • Administrative Contact:  Dana Johnson
Research Statement
  • Theoretical Astrophysics. Theoretical Nuclear and Elementary Particle Physics. Nuclear and Particle Astrophysics. General relativity, especially as regards instability in massive objects. Physics of the early universe; gravitational collapse and supernovae, compact objects; nuclear and quark matter; the origin of nuclei, especially the light elements in the Big Bang and the heavy elements in supernovae; the weak interaction and neutrinos. A common theme running through much of Professor Fullers work is the interplay of the weak interaction, nuclei, and gravitation.
Awards & News
  • Stepwise spectral swapping with three neutrino flavors
  • We develop a framework for studying collective three-flavor neutrino oscillations based on the density matrix formalism. We show how techniques proven useful for collective two-flavor neutrino oscillations such as corotating frames can be applied readily to three-flavor mixing. Applying two simple assumptions and the conservation of two "lepton numbers," we use this framework to demonstrate how the adiabatic/precession solution emerges. We illustrate with a numerical example how two stepwise spectral swaps appear naturally if the flavor evolution of the neutrino gas can be described by such a solution. For the special case where mu and tau flavor neutrinos are equally mixed and are produced with identical energy spectra and total numbers, we find that one of the spectral swaps in the three-flavor scenario agrees with that in the two-flavor scenario when appropriate mixing parameters are used. Using the corotating-frame technique we show how the adiabatic/precession solution can obtain even in the presence of a dominant ordinary matter background. With this solution we can explain why neutrino spectral swapping can be sensitive to deviations from maximal 23-mixing when the "mu-tau" matter term is significant. ©2008 The American Physical Society URL: http://link.aps.org/abstract/PRD/v77/e085016
  • UCSD's POLARBEAR experiment is moving to its permanent location in the Atacama Desert, Chile

  • Following a successful "first-light" four-month observing run, UCSD's POLARBEAR experiment on the Huan Tran Telescope at the James Ax Observatory located in the Inyo National Forest near Bishop, CA, is moving to its permanent location in the Atacama Desert, Chile.

    POLARBEAR is a collaboration between UC San Diego,
    UC Berkeley, University of Colorado, McGill University, Imperial College, the Japanese High Energy Research Organization, and the University of Paris.
    Polarbear's goal is to detect the gravitational waves produced during the era of inflation, shortly after the Big Bang by observing unique patterns of polarization of the Cosmic Microwave Background (CMB) radiation. These gravitational waves would be a telltale sign that inflation indeed took place. Additionally, measurement of the small angular scale polarization patterns have the capability to constrain the properties of Dark Matter and the mass of the neutrinos.

    POLARBEAR's receiver is able to detect the polarization of the CMB radiation through an array of over 1200 superconducting transition edge sensor bolometers cooled to 0.25 degrees Kelvin to reduce noise. Many months of observations must be combined to improve the signal to noise enough to observe the desired signals. Atmospheric water vapor is the enemy of ground-based
    microwave background measurements, hence the move to one of the driest sites on earth: the Atacama Desert, Chile where at an altitude of 16,500 feet, water vapor is greatly reduced.

    The POLARBEAR team has begun decommissioning the temporary observatory in the Inyo mountains which will be reassembled in Atacama for observations starting in early 2011.

    Polarbear team members from UC San Diego are David Boettger, George Fuller, Brian Keating, Nathan Miller, Hans Paar, and Ian Schanning.

  • UC San Diego Astrophysicist George Fuller Wins Hans Bethe Prize
  • George Fuller, an astrophysicist and professor of physics who directs UC San Diego's Center for Astrophysics and Space Sciences, known as CASS, has been selected to receive the 2013 Hans A. Bethe Prize.

    The prestigious award is given annually by the American Physical Society to "recognize outstanding work in theory, experiment or observation in the areas of astrophysics, nuclear physics, nuclear astrophysics, or closely related fields." The prize, which was established to honor Bethe, a renowned nuclear physicist at Cornell University, consists of $10,000 and a certificate citing the contributions made by the recipient.

    Fuller was cited for "outstanding contributions to nuclear astrophysics, especially his seminal work on weak interaction rates for stellar evolution and collapse and his pioneering research on neutrino flavor-mixing in supernovae." He will formally receive his award at a special session of the society's April 2013 meeting in Denver.

    Fuller has focused much of his recent research at CASS on the physics of the mysterious and ghostlike particles in the universe known as neutrinos, which hold the keys to physicists' improved understanding of cosmology, exploding stars called supernovae, and the origin of the elements. Fuller and his research group at UC San Diego have been calculating how neutrinos likely changed their "flavors" in the early universe, how they do so now within supernovae and how this process affects the synthesis of elements within stars--a process astrophysicists call nucleosynthesis.

    Fuller received his B.S. and Ph.D. degrees in physics from the California Institute of Technology. He was the Robert R. McCormick Postdoctoral Fellow at the University of Chicago from 1981 to 1983, a visiting research astrophysicist at UC Santa Cruz's Lick Observatory from 1983 to 1984 and a research assistant professor at the Institute for Nuclear Theory at the University of Washington from 1985 to 1986. He then was a staff member in the IGPP astrophysics group at Lawrence Livermore National Laboratory for two years before coming to UC San Diego in 1988 as an associate professor of physics. He was named a full professor in 1992, was promoted to Distinguished Professor in July and is a Fellow of the American Physical Society.

Selected Publications
  • - The Evolution of Non-Linear Sub-Horizon Scale Entropy Fluctuations in the Early Universe. With K. Jedamzik. Astrophys. J. 423, 33 (1994).

  • - Inhomogeneous Primordial Nucleosynthesis: Coupled Nuclear Reactions and Hydrodynamic Dissipation Processes. With K. Jedamzik and G.J. Mathews. Astrophys. J. 423, 50 (1994).

  • - Connection between Flavor Mixing of Cosmologically Significant Neutrinos and Heavy Element Nucleosynthesis in Supernovae. With Y.Z. Qian et al. Phys. Rev. Lett. 71, 1965 (1993).

  • - Can a Closure Mass Neutrino Help Solve the Supernova Shock Reheating Problem? With R. Mayle et al. Astrophys. J. 389, 517 (1992).

  • - Neutron Shell Blocking of Electron Capture During Gravitational Collapse. Astrophys. J. 252, 741 (1982).