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arXiv · 2503.19788

Macroscopic suppression of supersonic quantum transport

Jérémy Faupin·Marius Lemm·Israel Michael Sigal·Jingxuan Zhang
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Abstract

We consider a broad class of strongly interacting quantum lattice gases, including the Fermi-Hubbard and Bose-Hubbard models. We focus on macroscopic particle clusters of size $\theta N$, with $\theta\in(0,1)$ and $N$ the total particle number, and we study the quantum probability that such a cluster is transported across a distance $r$ within time $t$. Conventional effective light cone arguments yield a bound of the form $\exp(v t-r)$. We report a substantially stronger bound $\exp(\theta N(vt-r))$, which provides exponential suppression that scales with system size. Our result establishes a universal dynamical large deviation principle: macroscopic suppression of supersonic macroscopic transport (MASSMAT).

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Jérémy Faupin, Marius Lemm, Israel Michael Sigal, Jingxuan Zhang. 2025-03-25. Macroscopic suppression of supersonic quantum transport. https://arxiv.org/abs/2503.19788

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