English

Spectral function at high temperature in the classical approximation

High Energy Physics - Phenomenology 2009-11-07 v2 High Energy Physics - Lattice High Energy Physics - Theory

Abstract

At high temperature the infrared modes of a weakly coupled quantum field theory can be treated nonperturbatively in real time using the classical field approximation. We use this to introduce a nonperturbative approach to the calculation of finite-temperature spectral functions, employing the classical KMS condition in real time. The method is illustrated for the one-particle spectral function in a scalar field theory in 2+1 dimensions. The result is compared with resummed two-loop perturbation theory and both the plasmon mass and width are found to agree with the analytical prediction.

Keywords

Cite

@article{arxiv.hep-ph/0108125,
  title  = {Spectral function at high temperature in the classical approximation},
  author = {Gert Aarts},
  journal= {arXiv preprint arXiv:hep-ph/0108125},
  year   = {2009}
}

Comments

13 pages with 4 eps figures, minor changes; to appear in Phys.Lett.B