Quantum Variance and Ergodicity for the baker's map

Mirko Degli Esposti, Stéphane Nonnenmacher, Brian Winn

Published 2004-12-16, updated 2005-03-24Version 3

We prove a Egorov theorem, or quantum-classical correspondence, for the quantised baker's map, valid up to the Ehrenfest time. This yields a logarithmic upper bound for the decay of the quantum variance, and, as a corollary, a quantum ergodic theorem for this map.