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arXiv · 2604.19862

Bootstrapping Open Quantum Many-body Systems with Absorbing Phase Transitions

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

We demonstrate that combining the positivity of density matrices with steady-state conditions yields a systematic bootstrap method for studying open quantum many-body systems governed by Lindblad master equations on infinite lattices, which exhibit absorbing phase transitions. As a concrete example, we apply this method to the quantum contact process with an absorbing state. We obtain bootstrap bounds on steady-state expectation values, the critical coupling, certain ratios of expectation values in the nontrivial steady state in the supercritical phase, and the Liouvillian spectral gap in the subcritical phase.

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Minjae Cho, Colin Oscar Nancarrow, Petar Tadić, Yuan Xin. 2026-04-21. Bootstrapping Open Quantum Many-body Systems with Absorbing Phase Transitions. https://arxiv.org/abs/2604.19862

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