Theoretical Physics

My primary research is on the ab initio many-body theory and statistical mechanics of very strongly correlated quantum fluids. This includes the helium fluids, low density electron many-body systems and low density quantum plasmas, all of which have properties that cannot be well described by traditional quantum many-body theories such as mean field, Landau theory, density functional theory, or dynamic mean field theory. The challenges are due to the very strong correlations between the particles in these systems. To understand the consequences of these strong correlations, we have been heavily involved in the development of Dynamic Many-Body Theory, which recently has been highly successful in accounting exceedingly well for inelastic neutron scattering from superfluid liquid helium four. This theory and these experiments have revealed a much richer multi-quasiparticle dynamics than previously known. The experiments have been near absolute zero and the theory at absolute zero. We are continuing our work to extend the theory to finite temperature, including the phase transition from a normal fluid to a superfluid in liquid helium four.

Supersymmetric gauge theories, strong coupling phenomena, dynamical Casimir effect, black hole radiation

Theory of transport and electron-electron correlations in disordered systems, quantum Hall effect, hopping conduction, metal-nonmetal transition and transport in nano-crystal films.

• 1972-1982 and 1990-1995: QCD, Strong interaction Physics, Heavy Quark Physics, axions;
• 1982-1990 and since 1996: All aspects of supersymmetric theories at strong coupling;
• Since 2003: Supersymmetric solitons, sigma models (including applications in Condensed Matter).

I am interested in precision tests of the Standard Model in a variety of setting, from particle colliders to low-energy precision probes. A significant part of my research is devoted to the dark matter problem and new ideas that could help to discern its properties.