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Variational calculations in gauge theories with approximate projection on gauge invariant states

C. Heineman·C. Martin·D. Vautherin·E. Iancu
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Abstract

Variational calculations using Gaussian wave functionals combined with an approximate projection on gauge invariant states are presented. We find that the energy exhibits a minimum for a wave functional centered around a non vanishing background magnetic field. We show that divergences can be removed by a renormalization of the coupling constant. The resulting expectation value of the gluon condensate is found to be in qualitative agreement with phenomenological estimates.

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C. Heineman, C. Martin, D. Vautherin, E. Iancu. 1998-02-06. Variational calculations in gauge theories with approximate projection on gauge invariant states. https://arxiv.org/abs/hep-th/9802036

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