Hydrodynamic behavior near dynamical criticality of a facilitated conservative lattice gas

Clément Erignoux; Alexandre Roget; Assaf Shapira; Marielle Simon

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arXiv · 2403.09324

Hydrodynamic behavior near dynamical criticality of a facilitated conservative lattice gas

Clément Erignoux·Alexandre Roget·Assaf Shapira·Marielle Simon

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Abstract

We investigate a $2d$-conservative lattice gas exhibiting a dynamical active-absorbing phase transition with critical density $\rho_c$. We derive the hydrodynamic equation for this model, showing that all critical exponents governing the large scale behavior near criticality can be obtained from two independent ones. We show that as the supercritical density approaches criticality, distinct length scales naturally appear. Remarkably, this behavior is different from the subcritical one. Numerical simulations support the critical relations and the scale separation.

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Clément Erignoux, Alexandre Roget, Assaf Shapira, Marielle Simon. 2024-03-14. Hydrodynamic behavior near dynamical criticality of a facilitated conservative lattice gas. https://arxiv.org/abs/2403.09324

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