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arXiv · hep-th/9508148

The Vacuum Functional at Large Distances

Paul Mansfield
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Abstract

For fields that vary slowly on the scale of the lightest mass the logarithm of the vacuum functional can be expanded as a sum of local functionals, however this does not satisfy the obvious form of the Schrödinger equation. For $φ^4$ theory we construct the appropriate equation that this expansion does satisfy. This reduces the eigenvalue problem for the Hamiltonian to a set of algebraic equations. We suggest two approaches to their solution. The first is equivalent to the usual semi-classical expansion whilst the other is a new scheme that may also be applied to theories that are classically massless but in which mass is generated quantum mechanically.

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Paul Mansfield. 1995-08-28. The Vacuum Functional at Large Distances. https://doi.org/10.1016/0370-2693(95)01007-d

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