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arXiv · 1705.02862

Asymptotic analysis of the EPRL model with timelike tetrahedra

Wojciech Kaminski·Marcin Kisielowski·Hanno Sahlmann
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Abstract

We perform the stationary phase analysis of the vertex amplitude for the EPRL spin foam model extended to include timelike tetrahedra. We analyse both, tetrahedra of signature $---$ (standard EPRL), as well as of signature $+--$ (Hnybida-Conrady extension), in a unified fashion. However, we assume all faces to be of signature $--$. The stationary points of the extended model are described again by $4$-simplices and the phase of the amplitude is equal to the Regge action. Interestingly, in addition to the Lorentzian and Euclidean sectors there appear also split signature $4$-simplices.

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Wojciech Kaminski, Marcin Kisielowski, Hanno Sahlmann. 2017-05-08. Asymptotic analysis of the EPRL model with timelike tetrahedra. https://doi.org/10.1088/1361-6382%2Faac6a4

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