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arXiv · 2302.03053

Carrollian Origins of Bjorken Flow

Arjun Bagchi·Kedar S. Kolekar·Ashish Shukla
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Abstract

Bjorken flow is among the simplest models of fluids moving near the speed of light ($c$) while Carroll symmetry arises as a contraction of Poincar\'{e} group when $c \to 0$. We show that Bjorken flow and its phenomenological approximations are completely captured by Carrollian fluids. Carrollian symmetries arise on generic null surfaces and a fluid moving at $c$ is restricted to such a surface, thereby naturally inheriting the symmetries. Carrollian hydrodynamics is thus not exotic, but rather ubiquitous, and provides a concrete framework for fluids moving at or near the speed of light.

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Arjun Bagchi, Kedar S. Kolekar, Ashish Shukla. 2023-02-06. Carrollian Origins of Bjorken Flow. https://doi.org/10.1103/physrevlett.130.241601

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