Skeletons and Variation

Hermann Schulz

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arXiv · hep-ph/9808339

Skeletons and Variation

Hermann Schulz

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Abstract

Well known from the sixties, the pressure of e.g. massless phi-four theory may be written as a series of 2PI-diagrams (skeletons) with the lines fully dressed. Varying the self-energy Pi in this expression, it turns into a functional U[Y] having a maximum in function space at Y=Pi. There is also the Feynman-Jensen thermal variational principle V[S], a potentially non-perturbative tool. Here actions S are varied. It is shown, through a few formal but exact steps, that the functional U is covered by V. The corresponding special subset of trial actions is made explicit.

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Hermann Schulz. 1998-11-12. Skeletons and Variation. https://arxiv.org/abs/hep-ph/9808339

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