Trivial Lagrangians in the Causal Approach

Dan-Radu Grigore

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arXiv · 1508.02183

Trivial Lagrangians in the Causal Approach

Dan-Radu Grigore

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Abstract

We prove the non-uniqueness theorem for the chronological products of a gauge model. We use a cohomological language where the cochains are chronological products, gauge invariance means a cocycle restriction and coboundaries are expressions producing zero sandwiched between physical states. Suppose that we have gauge invariance up to order n of the perturbation theory and we modify the first-order chronological products by a coboundary (a trivial Lagrangian). Then the chronological products up to order n get modified by a coboundary also.

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Dan-Radu Grigore. 2015-08-10. Trivial Lagrangians in the Causal Approach. https://arxiv.org/abs/1508.02183

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