cond-mat/0005033 (Los Alamos) Presented at the 6th International Conference on Materials and Mechanisms of Superconductivity, Houston, February 2000 , Physica C 341-348, 213 (2000).
The apparently unrelated experimental observations of optical sum rule violation[1] and of tunneling asymmetry in NIS tunneling[2] find a simple explanation within the theory of hole superconductivity. In fact, both phenomena were predicted by the theory long before they were experimentally observed[3,4]. Other experimental predictions of the theory, in particular a novel feature expected in photoemission experiments, are discussed.