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arXiv · 0709.3227

Green functions and dimensional reduction of quantum fields on product manifolds

Z. Haba
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Abstract

We discuss Euclidean Green functions on product manifolds P=NxM. We show that if M is compact then the Euclidean field on P can be approximated by its zero mode which is a Euclidean field on N. We estimate the remainder of this approximation. We show that for large distances on N the remainder is small. If P=R^{D-1}xS^{beta}, where S^{beta} is a circle of radius beta, then the result reduces to the well-known approximation of the D dimensional finite temperature quantum field theory to D-1 dimensional one in the high temperature limit. Analytic continuation of Euclidean fields is discussed briefly.

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Z. Haba. 2008-02-15. Green functions and dimensional reduction of quantum fields on product manifolds. https://doi.org/10.1088/0264-9381%2F25%2F7%2F075005

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