Third Law of Thermodynamics as a Single Inequality
Abstract
The third law of thermodynamics in the form of the unattainability principle states that exact ground-state cooling requires infinite resources. Here we investigate the amount of non-equilibrium resources needed for approximate cooling. We consider as resource any system out of equilibrium, allowing for resources beyond the i.i.d. assumption and including the input of work as a particular case. We establish in full generality a sufficient and a necessary condition for cooling and show that for a vast class of non-equilibrium resources these two conditions coincide, providing a single necessary and sufficient criterion. Such conditions are expressed in terms of a single function playing a similar role for the third law to the one of the free energy for the second law. From a technical point of view we provide new results about concavity/convexity of certain Renyi-divergences, which might be of independent interest.
Keywords
Cite
@article{arxiv.1701.07478,
title = {Third Law of Thermodynamics as a Single Inequality},
author = {Henrik Wilming and Rodrigo Gallego},
journal= {arXiv preprint arXiv:1701.07478},
year = {2017}
}
Comments
Extended discussion on approximated and exact catalysts and models for the source of work. 22 pages. 2 Figures