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arXiv · hep-th/9507099

The gravitational polarization tensor of thermal $λϕ^4$ theory

H. Nachbagauer·A. K. Rebhan·D. J. Schwarz
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Abstract

The low-momentum structure of the gravitational polarization tensor of an ultrarelativistic plasma of scalar particles with $λϕ^4$ interactions is evaluated in a two-loop calculation up to and including order $λ^{3/2}$. This turns out to require an improved perturbation theory which resums a local thermal mass term as well as nonlocal hard-thermal-loop vertices of scalar and gravitational fields.

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H. Nachbagauer, A. K. Rebhan, D. J. Schwarz. 1995-07-19. The gravitational polarization tensor of thermal $λϕ^4$ theory. https://doi.org/10.1103/physrevd.53.882

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