# Dynamical renormalization group resummation of finite temperature infrared divergences

## Abstract

We introduce the method of dynamical renormalization group to study relaxation and damping out of equilibrium directly in real time and apply it to the study of infrared divergences in scalar QED. This method allows a consistent resummation of infrared effects associated with the exchange of quasistatic transverse photons and leads to anomalous logarithmic relaxation of the form e[sup [minus][alpha] hthinsp;T hthinsp;t hthinsp;ln[t/t[sub 0]]] for hard momentum charged excitations. This is in contrast with the usual quasiparticle interpretation of charged collective excitations at finite temperature in the sense of exponential relaxation of a narrow width resonance for which the width is the imaginary part of the self-energy on shell. In the case of narrow resonances away from thresholds, this approach leads to the usual exponential relaxation. The hard thermal loop resummation program is incorporated consistently into the dynamical renormalization group yielding a picture of relaxation and damping phenomena in a plasma in real time that transcends the conceptual limitations of the quasiparticle picture and other types of resummation schemes. [copyright] [ital 1999] [ital The American Physical Society]

- Authors:

- (Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States))
- (LPTHE, Universite Pierre et Marie Curie (Paris VI) et Denis Diderot (Paris VII), Tour 16, 1er. etage, 4, Place Jussieu, 75252 Paris, Cedex 05 (France))
- (Department of Physics, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213 (United States))
- (INFN, Gruppo Collegato di Parma (Italy))

- Publication Date:

- OSTI Identifier:
- 6296068

- Alternate Identifier(s):
- OSTI ID: 6296068

- Resource Type:
- Journal Article

- Journal Name:
- Physical Review, D

- Additional Journal Information:
- Journal Volume: 60:6; Journal ID: ISSN 0556-2821

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; INFRARED DIVERGENCES; PERTURBATION THEORY; QUANTUM CHROMODYNAMICS; QUANTUM ELECTRODYNAMICS; RENORMALIZATION; ELECTRODYNAMICS; FIELD THEORIES; QUANTUM FIELD THEORY 662220* -- Quantum Electrodynamics-- (1992-); 662230 -- Quantum Chromodynamics-- (1992-)

### Citation Formats

```
Boyanovsky, D., de Vega, H.J., Boyanovsky, D., de Vega, H.J., Simionato, M., Holman, R., and Simionato, M.
```*Dynamical renormalization group resummation of finite temperature infrared divergences*. United States: N. p., 1999.
Web. doi:10.1103/PhysRevD.60.065003.

```
Boyanovsky, D., de Vega, H.J., Boyanovsky, D., de Vega, H.J., Simionato, M., Holman, R., & Simionato, M.
```*Dynamical renormalization group resummation of finite temperature infrared divergences*. United States. doi:10.1103/PhysRevD.60.065003.

```
Boyanovsky, D., de Vega, H.J., Boyanovsky, D., de Vega, H.J., Simionato, M., Holman, R., and Simionato, M. Wed .
"Dynamical renormalization group resummation of finite temperature infrared divergences". United States. doi:10.1103/PhysRevD.60.065003.
```

```
@article{osti_6296068,
```

title = {Dynamical renormalization group resummation of finite temperature infrared divergences},

author = {Boyanovsky, D. and de Vega, H.J. and Boyanovsky, D. and de Vega, H.J. and Simionato, M. and Holman, R. and Simionato, M.},

abstractNote = {We introduce the method of dynamical renormalization group to study relaxation and damping out of equilibrium directly in real time and apply it to the study of infrared divergences in scalar QED. This method allows a consistent resummation of infrared effects associated with the exchange of quasistatic transverse photons and leads to anomalous logarithmic relaxation of the form e[sup [minus][alpha] hthinsp;T hthinsp;t hthinsp;ln[t/t[sub 0]]] for hard momentum charged excitations. This is in contrast with the usual quasiparticle interpretation of charged collective excitations at finite temperature in the sense of exponential relaxation of a narrow width resonance for which the width is the imaginary part of the self-energy on shell. In the case of narrow resonances away from thresholds, this approach leads to the usual exponential relaxation. The hard thermal loop resummation program is incorporated consistently into the dynamical renormalization group yielding a picture of relaxation and damping phenomena in a plasma in real time that transcends the conceptual limitations of the quasiparticle picture and other types of resummation schemes. [copyright] [ital 1999] [ital The American Physical Society]},

doi = {10.1103/PhysRevD.60.065003},

journal = {Physical Review, D},

issn = {0556-2821},

number = ,

volume = 60:6,

place = {United States},

year = {1999},

month = {9}

}