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Divergences in the Effective Action for Acausal Spacetimes

M. J. Cassidy
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Abstract

The 1--loop effective Lagrangian for a massive scalar field on an arbitrary causality violating spacetime is calculated using the methods of Euclidean quantum field theory in curved spacetime. Fields of spin 1/2, spin 1 and twisted field configurations are also considered. In general, we find that the Lagrangian diverges to minus infinity at each of the nth polarised hypersurfaces of the spacetime with a structure governed by a DeWitt-Schwinger type expansion.

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M. J. Cassidy. 1997-05-28. Divergences in the Effective Action for Acausal Spacetimes. https://doi.org/10.1088/0264-9381%2F14%2F11%2F006

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