Two University of Rochester scientists have been elected to fellowship positions in the American Physical Society. Ashok Das and David Meherhofer were honored for their accomplishments in physics. Less than one-half of one percent of the membership of the society is elected as fellows.

Ashok Das, professor of physics and astronomy, was elected for his work in theoretical physics, specifically in supergravity, integrable models, and finite temperature field theory.

Supergravity is a theory that was once expected to reconcile one of the greatest conundrums in physics. Of the four forces in nature, three are known to have a common origin, but the fourth force, gravity, has so far eluded scientists' endeavors to unify it with the other three. String theory, one of the most popular of the unifying theories, is an offshoot of the supergravity theory. Das was part of the team that figured out how to allow the first three forces to be included in this supergravity theory.

Das was also recognized for his work in clarifying many of the subtleties that arise in physics under extreme temperatures, such as the beginning stages of the universe or heavy ion reactions in nuclear accelerators. He has also helped to clarify certain key theoretical aspects of models of physical interactions which are solvable. His books on finite temperature field theory as well as integrable models are widely used all over the world.

David Meyerhofer, experimental division director and senior scientist at the Universities Laboratory for Laser Energetics (LLE) and professor of mechanical engineering and physics, was elected a fellow of the American Physical Society for his contributions to direct-drive confinement fusion and high-intensity laser-matter interactions. At LLE, Meyerhofer uses the OMEGA laser, the world's most powerful, to study high energy density physics and nuclear fustion. Such experiments pave the way both for understanding the very nature of matter and might also lead to a clean, renewable energy source.

Meyerhofer experiments to understand how high intensity lasers interact with matter have included strong field atomic physics and, in collaboration with a team from the University of Rochester, the University of Tennessee, Princeton University, and the Stanford Linear Accelerator Center, the observation of electron-positron pair production in light-by-light scattering.