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arXiv · 2609.23004

Quantitative decomposition and approximation for quasi-local operators

Jiawen Zhang·Jingming Zhu
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Abstract

We develop a quantitative approach to quasi-local operators with bounded block-rank. Our main results are a quantitative decomposition for quasi-local operators into block-rank-one pieces and a quantitative finite-propagation approximation in the block-rank-one case, leading to a quantitative proof of the bounded block-rank rigidity result for Roe and quasi-local algebras.

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Jiawen Zhang, Jingming Zhu. 2026-09-19. Quantitative decomposition and approximation for quasi-local operators. https://arxiv.org/abs/2609.23004

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