# Real-time finite-temperature Green functions for nonuniform nonequilibrium media

## Abstract

A nonequilibrium generating functional for Green functions and finite-temperature diagrams for a nonuniform nonstationary scalar field are constructed as an expansion in powers of the temperature gradients. It is shown that time arguments of operators in the nonequilibrium case may be defined on the same contour as in the equilibrium case. The expressions for propagators and vertices up to first-order corrections in temperature gradients are given. It is shown that they are free from pinch singularities. The renormalization of mass and coupling constant is the same as at zero temperature only if the energy-momentum tensor is chosen in an improved form. The change of the local phase transition temperature in a spontaneously broken scalar field theory due to gradients and time derivatives of temperature is calculated. The free energy density in the low and high temperature limits is computed. 40 refs.

- Authors:

- (Inst. of Physics, Tbilisi (Georgia))
- (Tel Aviv Univ. (Israel))

- Publication Date:

- OSTI Identifier:
- 6647089

- Alternate Identifier(s):
- OSTI ID: 6647089

- Resource Type:
- Journal Article

- Journal Name:
- Annals of Physics (New York); (United States)

- Additional Journal Information:
- Journal Volume: 220:1; Journal ID: ISSN 0003-4916

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; GREEN FUNCTION; DIAGNOSTIC USES; PARTICLES; MOTION; DENSITY MATRIX; ENERGY DENSITY; ENERGY-MOMENTUM TENSOR; FREE ENERGY; HYDRODYNAMICS; MATHEMATICAL MODELS; RENORMALIZATION; TEMPERATURE GRADIENTS; TRANSITION TEMPERATURE; ENERGY; FLUID MECHANICS; FUNCTIONS; MATRICES; MECHANICS; PHYSICAL PROPERTIES; TENSORS; THERMODYNAMIC PROPERTIES; USES 661300* -- Other Aspects of Physical Science-- (1992-); 990200 -- Mathematics & Computers

### Citation Formats

```
Bibilashvili, T., and Paziashvili, I.
```*Real-time finite-temperature Green functions for nonuniform nonequilibrium media*. United States: N. p., 1992.
Web. doi:10.1016/0003-4916(92)90328-J.

```
Bibilashvili, T., & Paziashvili, I.
```*Real-time finite-temperature Green functions for nonuniform nonequilibrium media*. United States. doi:10.1016/0003-4916(92)90328-J.

```
Bibilashvili, T., and Paziashvili, I. Sun .
"Real-time finite-temperature Green functions for nonuniform nonequilibrium media". United States. doi:10.1016/0003-4916(92)90328-J.
```

```
@article{osti_6647089,
```

title = {Real-time finite-temperature Green functions for nonuniform nonequilibrium media},

author = {Bibilashvili, T. and Paziashvili, I.},

abstractNote = {A nonequilibrium generating functional for Green functions and finite-temperature diagrams for a nonuniform nonstationary scalar field are constructed as an expansion in powers of the temperature gradients. It is shown that time arguments of operators in the nonequilibrium case may be defined on the same contour as in the equilibrium case. The expressions for propagators and vertices up to first-order corrections in temperature gradients are given. It is shown that they are free from pinch singularities. The renormalization of mass and coupling constant is the same as at zero temperature only if the energy-momentum tensor is chosen in an improved form. The change of the local phase transition temperature in a spontaneously broken scalar field theory due to gradients and time derivatives of temperature is calculated. The free energy density in the low and high temperature limits is computed. 40 refs.},

doi = {10.1016/0003-4916(92)90328-J},

journal = {Annals of Physics (New York); (United States)},

issn = {0003-4916},

number = ,

volume = 220:1,

place = {United States},

year = {1992},

month = {11}

}