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arXiv · 1201.0716

Concavification of free entropy

Philippe Biane·Yoann Dabrowski
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Abstract

We introduce a modification of Voiculescu's free entropy which coincides with the liminf variant of Voiculescu's free entropy on extremal states, but is a concave upper semi-continuous function on the trace state space. We also extend the orbital free entropy of Hiai, Miyamoto and Ueda to non-hyperfinite multivariables and prove freeness in case of additivity of Voiculescu's entropy (or vanishing of our extended orbital entropy).

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Philippe Biane, Yoann Dabrowski. 2012-11-12. Concavification of free entropy. https://arxiv.org/abs/1201.0716

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