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arXiv · 2211.16430

Entanglement Entropy, Local IR/UV Connection and MPS in Weyl-deformed Geometries

Leo Shaposhnik
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Abstract

We study the behaviour of entanglement entropy in two-dimensional CFTs under Weyl transformations from the Weyl anomaly. Using the Ryu-Takayanagi-formula, we show that these deformations correspond to local deformations of the IR cutoff of AdS$_3$, which gives an example of the local validity of the IR/UV Connection in AdS/CFT. We then use Matrix Product States to demonstrate the behaviour of entanglement entropy under Weyl transformations in the two-dimensional free fermion CFT mapped to the XY-model with site-dependent coupling. We present numerical results for different deformations of the background and discuss issues arising for the standard DMRG procedure for the resulting inhomogeneous interactions due to a nontrivial background.

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Leo Shaposhnik. 2022-11-29. Entanglement Entropy, Local IR/UV Connection and MPS in Weyl-deformed Geometries. https://arxiv.org/abs/2211.16430

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