Screened perturbation theory
Abstract
A new perturbative scheme is proposed for the evaluation of the free energy density of field theories at finite temperature. The screened loop expansion takes into account exactly the phenomenon of screening in thermal propagators. The approach is tested in the Ncomponent scalar field theory at 2loop level and also at 3loop in the largeN limit. The perturbative series generated by the screened loop expansion shows much better numerical convergence than previous expansions generated in powers of the quartic coupling.
 Publication:

Physics Letters B
 Pub Date:
 February 1997
 DOI:
 10.1016/S03702693(97)003924
 arXiv:
 arXiv:hepph/9702376
 Bibcode:
 1997PhLB..401...69K
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 10 pages, LaTex, 2 figures