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arXiv · 1406.2716

Entanglement Entropy Flow and the Ward Identity

Vladimir Rosenhaus·Michael Smolkin
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Abstract

We derive differential equations for the flow of entanglement entropy as a function of the metric and the couplings of the theory. The variation of the universal part of entanglement entropy under a local Weyl transformation is related to the variation under a local change in the couplings. We show that this relation is in fact equivalent to the trace Ward identity. As a concrete application of our formalism, we express the entanglement entropy for massive free fields as a two-point function of the energy-momentum tensor.

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Vladimir Rosenhaus, Michael Smolkin. 2014-06-16. Entanglement Entropy Flow and the Ward Identity. https://doi.org/10.1103/physrevlett.113.261602

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