### 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 N-component scalar field theory at 2-loop level and also at 3-loop in the large-N 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.

Original language | English |
---|---|

Pages (from-to) | 69-73 |

Number of pages | 5 |

Journal | Physics Letters B |

Volume | 401 |

Issue number | 1-2 |

Publication status | Published - May 22 1997 |

### Fingerprint

### Keywords

- Debye screening
- Free energy density
- Gap equation
- High-T expansion
- Loop expansion
- QCD
- Scalar field theory

### ASJC Scopus subject areas

- Nuclear and High Energy Physics

### Cite this

*Physics Letters B*,

*401*(1-2), 69-73.

**Screened perturbation theory.** / Karsch, F.; Patkós, A.; Petreczky, P.

Research output: Contribution to journal › Article

*Physics Letters B*, vol. 401, no. 1-2, pp. 69-73.

}

TY - JOUR

T1 - Screened perturbation theory

AU - Karsch, F.

AU - Patkós, A.

AU - Petreczky, P.

PY - 1997/5/22

Y1 - 1997/5/22

N2 - 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 N-component scalar field theory at 2-loop level and also at 3-loop in the large-N 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.

AB - 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 N-component scalar field theory at 2-loop level and also at 3-loop in the large-N 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.

KW - Debye screening

KW - Free energy density

KW - Gap equation

KW - High-T expansion

KW - Loop expansion

KW - QCD

KW - Scalar field theory

UR - http://www.scopus.com/inward/record.url?scp=0001954141&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001954141&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0001954141

VL - 401

SP - 69

EP - 73

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

IS - 1-2

ER -