Dimensional Reduction and Quantum-to-Classical Reduction at High Temperatures

Abstract

We discuss the relation between dimensional reduction in quantum field theories at finite temperature and a familiar quantum mechanical phenomenon that quantum effects become negligible at high temperatures. Fermi and Bose fields are compared in this respect. We show that decoupling of fermions from the dimensionally reduced theory can be related to the non-existence of classical statistics for a Fermi field.

Comments: 11 pages, REVTeX, revised v. to be published in Phys. Rev. D: some points made more explicit