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arXiv · 2206.11874

A saddle-point finder and its application to the spin foam model

Zichang Huang·Shan Huang·Yidun Wan
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Abstract

We introduce a saddle-point finder that can find the complex saddle points for any analytically continued action. We showcase our saddle-point finder by two examples in the EPRL spin foam model: the single vertex case and the case of triangulation $\Delta_3$. In both cases, the complex saddle points are found, and each saddle point's contribution to the partition function is estimated. We also discuss the geometrical interpretation of each saddle point.

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Zichang Huang, Shan Huang, Yidun Wan. 2022-06-23. A saddle-point finder and its application to the spin foam model. https://doi.org/10.1103/physrevd.107.046011

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