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arXiv · 2103.08631

Hyper-Invariant MERA: Approximate Holographic Error Correction Codes with Power-Law Correlations

ChunJun Cao·Jason Pollack·Yixu Wang
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Abstract

We consider a class of holographic tensor networks that are efficiently contractible variational ansatze, manifestly (approximate) quantum error correction codes, and can support power-law correlation functions. In the case when the network consists of a single type of tensor that also acts as an erasure correction code, we show that it cannot be both locally contractible and sustain power-law correlation functions. Motivated by this no-go theorem, and the desirability of local contractibility for an efficient variational ansatz, we provide guidelines for constructing networks consisting of multiple types of tensors that can support power-law correlation. We also provide an explicit construction of one such network, which approximates the holographic HaPPY pentagon code in the limit where variational parameters are taken to be small.

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ChunJun Cao, Jason Pollack, Yixu Wang. 2021-03-15. Hyper-Invariant MERA: Approximate Holographic Error Correction Codes with Power-Law Correlations. https://doi.org/10.1103/physrevd.105.026018

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