These lecture notes provide an elementary introduction, within the framework of finite quantum systems, to recent developments in the theory of entropic fluctuations.
Entropic Fluctuation Theorems for the Spin-Fermion Model
Institut de Mathématiques de Toulouse, UMR5219Université de Toulouse, CNRS, UPS IMT(图卢兹数学研究所);Département de Mathématiques, CNRS UMR 8088Cergy Paris Université(塞吉巴黎大学);Dipartimento di MatematicaPolitecnico di Milano(米兰理工大学);Université de Toulon, CNRS, CPT, UMR 7332(土伦大学);Aix-Marseille Université, CNRS, CPT, UMR 7332(艾克斯-马赛大学)
Entropic fluctuations in XY chains and reflectionless Jacobi matrices
We study the entropic fluctuations of a general XY spin chain where initially the left(x<0)/right(x>0) part of the chain is in thermal equilibrium at inverse temperature Tl/Tr. The temperature differential results in a non-trivial energy/entropy flux across the chain. The Evans-Searles (ES) entropic functional describes fluctuations of the flux observable with respect to the initial state while the Gallavotti-Cohen (GC) functional describes these fluctuations with respect to the steady state (NESS) the chain reaches in the large time limit. We also consider the full counting statistics (FCS) o…