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arXiv · hep-th/9811182

Large Gauge Transformations and the Light-Front Vacuum Structure

L. Martinovic
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Abstract

A residual gauge symmetry, exhibited by light-front gauge theories quantized in a finite volume, is analyzed at the quantum level. Unitary operators, which implement the symmetry, transform the trivial Fock vacuum into an infinite set of degenerate coherent-state vacua. A fermionic component of the vacuum emerges naturally without the need to introduce a Dirac sea. The vacuum degeneracy along with the derivation of the theta-vacuum is discussed within the massive Schwinger model. A possible generalization of the approach to more realistic gauge theories is suggested.

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L. Martinovic. 1998-11-20. Large Gauge Transformations and the Light-Front Vacuum Structure. https://doi.org/10.1016/s0370-2693(01)00507-x

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