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Enlarged geometries of gauge bundles

R. Aldrovandi·A. L. Barbosa
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Abstract

The geometrical picture of gauge theories must be enlarged when a gauge potential ceases to behave like a connection, as it does in electroweak interactions. When the gauge group has dimension four, the vector space isomorphism between spacetime and the gauge algebra is realized by a tetrad-like field. The object measuring the deviation from a strict bundle structure has the formal behavior of a spacetime connection, of which the deformed gauge field-strength is the torsion. A generalized derivative emerges in terms of which the two Bianchi identities are formally recovered. Effects of gravitational type turn up. The dynamical equations obtained correspond to a broken gauge model on a curved spacetime.

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R. Aldrovandi, A. L. Barbosa. 2001-07-20. Enlarged geometries of gauge bundles. https://arxiv.org/abs/math-ph/0107021

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