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arXiv · 1407.8387

Spectral functions from the functional renormalization group at finite temperature and density

Ralf-Arno Tripolt·Nils Strodthoff·Lorenz von Smekal·Jochen Wambach
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Abstract

We present a viable method to obtain real-time quantities such as spectral functions or transport coefficients at finite temperature and density within a non-perturbative Functional Renormalization Group approach. Our method is based on a thermodynamically consistent truncation of the flow equations for 2-point functions with analytically continued frequency components in the originally Euclidean external momenta. We demonstrate its feasibility by calculating the mesonic spectral functions in the quark-meson model at different temperatures and quark chemical potentials, in particular around the critical endpoint in the phase diagram of the model.

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Ralf-Arno Tripolt, Nils Strodthoff, Lorenz von Smekal, Jochen Wambach. 2014-07-31. Spectral functions from the functional renormalization group at finite temperature and density. https://doi.org/10.1016/j.nuclphysa.2014.09.061

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