Divergences in the Effective Action for Acausal Spacetimes
نویسنده
چکیده
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 12 , 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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تاریخ انتشار 2008