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arXiv · 2412.07837

Coarse-grained Bootstrap of Quantum Many-body Systems

Minjae Cho·Colin Oscar Nancarrow·Petar Tadić·Yuan Xin·Zechuan Zheng
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Abstract

We present a new computational framework combining coarse-graining techniques with bootstrap methods to study quantum many-body systems. The method efficiently computes rigorous upper and lower bounds on both zero- and finite-temperature expectation values of any local observables of infinite quantum spin chains. This is achieved by using tensor networks to coarse-grain bootstrap constraints, including positivity, translation invariance, equations of motion, and energy-entropy balance inequalities. Coarse-graining allows access to constraints from significantly larger subsystems than previously possible, yielding tighter bounds compared to those obtained without coarse-graining.

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Minjae Cho, Colin Oscar Nancarrow, Petar Tadić, Yuan Xin, Zechuan Zheng. 2025-11-22. Coarse-grained Bootstrap of Quantum Many-body Systems. https://arxiv.org/abs/2412.07837

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