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arXiv · 2609.35164

Relaxation-Time Boltzmann Solutions Without Truncations

Tiago Nunes da Silva·Jadna L. Barauna·Giorgio Torrieri
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Abstract

The relaxation-time Boltzmann equation governs relativistic matter far from equilibrium, but existing approaches rely on finite-order truncations that break down in this regime. We introduce ShARK (Stochastic Advection Relaxation Kinetics), the first fully 3D Monte Carlo kinetic framework to capture exact, far-from-equilibrium ultrarelativistic dynamics for arbitrary initial conditions while directly enforcing target transport coefficients, converging to the exact Anderson-Witting solution. Validated against the Bjorken and Gubser flows, the framework reproduces the exact kinetic result where truncated methods fail.

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Tiago Nunes da Silva, Jadna L. Barauna, Giorgio Torrieri. 2026-09-28. Relaxation-Time Boltzmann Solutions Without Truncations. https://arxiv.org/abs/2609.35164

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