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arXiv · hep-ph/0207119

Kamlah Expansion and Gauge Theories

Oliver Schroeder·Hugo Reinhardt
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Abstract

In Yang-Mills theories, variational calculations of the Rayleigh-Ritz type face the problem that on the one hand, calculability puts severe constraints on the space of test wave functionals; on the other hand, the test wave functionals have to be gauge invariant. The conflict between the two requirements can be resolved by introducing a projector. In this paper we present an approach to approximating the projector in a way known and successfully employed in nuclear physics: the Kamlah expansion. We discuss it both for electrodynamics and for Yang-Mills theories to leading order in a perturbative expansion, and demonstrate that the results are compatible with what one would expect from perturbation theory.

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Oliver Schroeder, Hugo Reinhardt. 2002-07-09. Kamlah Expansion and Gauge Theories. https://doi.org/10.1016/j.aop.2004.03.007

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