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arXiv · 2605.03020

Exact Quantum Many-Body Scars by a generalized Matrix-Product Ansatz

Sascha Gehrmann·Fabian H. L. Essler
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Abstract

We construct exact eigenstates of quantum many-body systems with Hamiltonians that are not frustration-free in matrix product form, based on a local error cancellation ansatz motivated by the Derrida-Evans-Hakim-Pasquier method for finding the stationary state of the asymmetric simple exclusion process. We demonstrate the approach with explicit examples in both one and two spatial dimensions.

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Sascha Gehrmann, Fabian H. L. Essler. 2026-05-04. Exact Quantum Many-Body Scars by a generalized Matrix-Product Ansatz. https://arxiv.org/abs/2605.03020

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