nLab infinite-temperature thermal field theory

Contents

Context

Quantum Field Theory

algebraic quantum field theory (perturbative, on curved spacetimes, homotopical)

Introduction

Concepts

field theory:

Lagrangian field theory

quantization

quantum mechanical system, quantum probability

free field quantization

gauge theories

interacting field quantization

renormalization

Theorems

States and observables

Operator algebra

Local QFT

Perturbative QFT

Measure and probability theory

Contents

Idea

Broadly speaking, high- or infinite-temperature thermal field theory is thermal field theory in or around the limiting case of very high or (practically) infinite temperature TT.

This is relevant for example in the study of extreme phases of matter such as the quark-gluon plasma of QCD (Blaizot-Iancu-Rebhan 03, section 2.2.4, Blaizot 04, around p. 17).

More concretely, with the formulation of thermal field theory via Wick rotation as a Euclidean field theory on a Riemannian manifold X 3×S β 1X_3 \times S^1_\beta whose compact/periodic Euclidean time runs along a circle S β 1S^1_\beta of circumference the inverse temperature β=1/T\beta = 1/T, the limit of infinite temperature corresponds to the limit β0\beta \to 0 in which this circle fiber shrinks away.

In terms of the thermal Euclidean field theory on X 3×S β 1X_3 \times S^1_\beta therefore the infinite-temperature limit is given by Kaluaza-Klein-type dimensional reduction along this circle fiber to a 3-dimensional Euclidean field theory on X 3X_3 (Ginsparg 80, Appelquist-Pisarski 81, Nadkarni 83, Jourjine 84, Nadkarni 88).

As usual with KK-reduction, some care must be exercised to ensure that the compactified theory is itself still a local field theory. Depending on how exactly one proceeds this may be subtle (Landsman 89), but there exist robust approaches (Reisz 92, Kajantie-Laine-Rummukainen-Shaposhnikov 96).

References

The expansion of thermal field theory around the infinite-temperature-limit (i.e. around β=1/T=0\beta = 1/T = 0, i.e. KK-reduction in compact/periodic Euclidean time) is discussed in

and specifically with an eye to discussion of the quark-gluon plasma in

  • Jean-Paul Blaizot, Edmond Iancu, Anton Rebhan, section 2.2.4 of Thermodynamics of the high temperature quark gluon plasma, Quark–Gluon Plasma 3, pp. 60-122 (2004) (arXiv:hep-ph/0303185, spire:615570)

  • Jean-Paul Blaizot, around p. 17 of Thermodynamics of the high temperature Quark-Gluon Plasma, AIP Conf. Proc. 739, 63-96 (2004) (doi:10.1063/1.1843592)

Review:

Last revised on November 6, 2024 at 05:06:33. See the history of this page for a list of all contributions to it.