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arXiv · 1401.3752

Unitarity in a Lorentz symmetry breaking model with higher-order operators

Markos Maniatis·Carlos M. Reyes
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Abstract

We analyze the unitarity of a modified QED with higher-order terms that violate Lorentz symmetry. We make an explicit calculation to verify unitarity at the one-loop level. As expected we find negative norm states that could in principle lead to a violation of unitarity. However, we show that these states become massive in Euclidean space and do not contribute to the discontinuity.

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Markos Maniatis, Carlos M. Reyes. 2014-01-15. Unitarity in a Lorentz symmetry breaking model with higher-order operators. https://doi.org/10.1103/physrevd.89.056009

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