Friday, September 16, 2005

Prof. Jorge Hirsch

Department of Physics, UC San Diego

"Superconductors, Tao balls, and macroscopic atoms: could a 70-year old theory be wrong?"

2:00 pm in room P-148

Abstract:  When Rongjia Tao recently applied an electric field to millions of superconducting microparticles in suspension he discovered a surprising new effect(1): they fly towards each other, clumping up into a tightly bound round ball of mm-size radius. Neither London nor BCS, the founders of the currently established understanding of superconductivity, expected this, nor do they have any clue as to why this occurs. To me, Tao balls look like giant atoms, and the phenomenon is a manifestation of the fundamental charge asymmetry of matter that is at the root of the phenomenon of superconductivity according to the unconventional theory of "hole superconductivity"(2). I will present the essential elements of this theory, developed over the past 15 years, describe how it explains the "Tao effect", and discuss other experiments that could be done to decide on its ultimate validity or invalidity.

(1) R. Tao, X. Xu and E. Amr, Physica C 398, 78 (2003) and references therein.

(2) J.E. Hirsch, Phys.Rev. Lett. 94, 187001 (2005) and references therein.