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arXiv · 1403.7640

Correlation in fermion or boson systems as the minimum of entropy relative to all free states

Alex D. Gottlieb·Norbert J. Mauser
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Abstract

In the context of many-fermion systems, "correlation" refers to the inadequacy of an independent-particle model. Using "free" states as archetypes of our independent-particle model, we have proposed a measure of correlation that we called "nonfreeness" [Int. J. Quant. Inf. 5, 815 (2007)]. The nonfreeness of a many-fermion state was defined to be its entropy relative to the unique free state with the same 1-matrix. In this article, we prove that the nonfreeness of a state is the minimum of its entropy relative to all free states. We also extend the definition of nonfreeness to many-boson states and discuss a couple of examples.

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Alex D. Gottlieb, Norbert J. Mauser. 2014-03-29. Correlation in fermion or boson systems as the minimum of entropy relative to all free states. https://arxiv.org/abs/1403.7640

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