Consistency of field-theoretical and kinetic calculations of viscous transport coefficients for a relativistic fluid

TL;DR

This paper compares field-theoretical and kinetic calculations of viscous transport coefficients in relativistic fluids, revealing modifications to traditional kinetic results and agreement with field-theoretical results under certain conditions.

Contribution

It introduces revised expressions for viscous transport coefficients that align with field-theoretical calculations when pair creation and annihilation are ignored.

Findings

Traditional kinetic results are modified.

Revised coefficients agree with field-theoretical results.

Pair creation and annihilation contributions are significant.

Abstract

The transport coefficients of causal relativistic dissipative fluid dynamics are calculated both in a field-theoretical and a kinetic approach. We find that the results from the traditional kinetic calculation by Israel and Stewart are modified. The new expressions for the viscous transport coefficients agree with the results obtained in the field-theoretical approach when the contributions from pair creation and annihilation are neglected.