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arXiv · 2208.10502

Determining all thermodynamic transport coefficients for an interacting large N quantum field theory

Max Weiner·Paul Romatschke
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Abstract

Thermodynamic transport coefficients can be calculated directly from quantum field theory without requiring analytic continuation to real time. We determine all second-order thermodynamic transport coefficients for the uncharged N-component massless (critical) scalar field theory with quartic interaction in the large N limit, for any value of the coupling. We find that in the large N limit, all thermodynamic transport coefficients for the interacting theory can be expressed analytically in terms of the in-medium mass and sums over modified Bessel functions. We expect our technique to allow a similar determination of all thermodynamic transport coefficients for all theories that are solvable in the large N limit, including certain gauge theories.

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Max Weiner, Paul Romatschke. 2022-08-22. Determining all thermodynamic transport coefficients for an interacting large N quantum field theory. https://doi.org/10.1007/jhep01(2023)046

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