Isotropization in heavy ion collisions in the 2PI formalism

Francois Gelis

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arXiv · 2509.17668

Isotropization in heavy ion collisions in the 2PI formalism

Francois Gelis

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Abstract

An important question in heavy-ion collisions is how the initial far-from-equilibrium medium evolves and thermalizes while it undergoes a rapid longitudinal expansion. In this presentation, we show how to use the two-particle irreducible (2PI) effective action to address this question, focusing on $\phi^4$ scalar theory truncated at three loops. We present numerical results for quantities such as the occupation number, the thermal mass, and the number density.

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Francois Gelis. 2025-09-22. Isotropization in heavy ion collisions in the 2PI formalism. https://arxiv.org/abs/2509.17668

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