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arXiv · 2504.04304

Universality in many-body driven systems with an umbilic point

Johannes Schmidt·Žiga Krajnik·Vladislav Popkov
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Abstract

We study stationary fluctuations of conserved slow modes in a two-lane model of hardcore particles which are expected to show universal behaviour. Specifically, we focus on the properties of fluctuations at a special umbilic point where the characteristic velocities coincide. At large space and time scales, fluctuations are described by a system of stochastic Burgers equations studied recently in [13]. Our data suggest coupling-dependent scaling functions and, even more surprisingly, coupling-dependent dynamical scaling exponents, distinct from KPZ scaling exponent typical for surface growth processes.

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Johannes Schmidt, Žiga Krajnik, Vladislav Popkov. 2025-04-05. Universality in many-body driven systems with an umbilic point. https://doi.org/10.1088/1742-5468%2Fadefaf

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