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arXiv · 0908.1737

Entanglement Entropy at Finite Density from Extremal Black Holes

Brian Swingle
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Abstract

I compute the entanglement entropy of a strongly coupled 2+1d quantum field theory containing fermions at finite density using gauge/gravity duality. The dual geometry is an extremal black hole in 3+1d Einstein-Maxwell theory. This system was recently shown to exhibit non-Fermi liquid behavior, but the leading geometrical contribution to the entanglement entropy does not produce an expected violation of the boundary law. I discuss this negative result in the context of attempts to find highly entangled states of quantum matter.

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Brian Swingle. 2009-08-19. Entanglement Entropy at Finite Density from Extremal Black Holes. https://arxiv.org/abs/0908.1737

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