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arXiv · hep-th/9807032

Non-perturbative VEVs from a Local Expansion

A. Jaramillo·P. Mansfield
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Abstract

We propose a method for the calculation of vacuum expectation values (VEVs) given a non-trivial, long-distance vacuum wave functional (VWF) of the kind that arises, for example, in variational calculations. The VEV is written in terms of a Schrödinger-picture path integral, then a local expansion for (the logarithm of the) VWF is used. The integral is regulated with an explicit momentum cut-off, $Λ$. The resulting series is not expected to converge for $Λ$ larger than the mass-gap but studying the domain of analyticity of the VEVs allows us to use analytic continuation to estimate the large-$Λ$ limit. Scalar theory in 1+1 dimensions is analyzed, where (as in the case of Yang-Mills) we do not expect boundary divergences.

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A. Jaramillo, P. Mansfield. 1998-07-03. Non-perturbative VEVs from a Local Expansion. https://arxiv.org/abs/hep-th/9807032

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