13/12/2013, 16:15 — 17:15 — Room P3.10, Mathematics Building
Marco Pezzuto, University of Trieste
Entanglement and the second law of thermodynamics
Under certain assumptions, it is possible to define for an open quantum system many key thermodynamic quantities, such as the internal energy, entropy, exchanged heat and work. By means of these quantities, the zeroth, first and second law of thermodynamics can also be given a consistent formulation.
A brief introduction on the dynamics of open quantum systems will be given, together with a review of the concepts of positivity and complete positivity in relation with entanglement.
Afterwards, it will be shown how to define the law of thermodynamics, and specifically the second one in terms of positivity of the internal entropy production, and the connections with complete positivity of the dynamics. Such techniques have been applied to a concrete case, namely a model for a quantum pumping process in a noisy environment. The master equation originally proposed for this model turns out to provide a non-completely positive dynamics, and it was found that, in certain conditions, this fact can lead to consequences from a thermodynamical point of view, such as violations of the second law.
Complete positivity, beside guaranteeing a physically consistent description when entanglement is taken into account, seems then to gain an important role in relation to thermodynamics.