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arXiv · 2007.01998

Numerical computations of next-to-leading order corrections in spinfoam large-$j$ asymptotics

Muxin Han·Zichang Huang·Hongguang Liu·Dongxue Qu
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Abstract

We numerically study the next-to-leading order corrections of the Lorentzian Engle-Pereira-Rovelli-Livine (EPRL) 4-simplex amplitude in the large-$j$ expansions. We perform large-$j$ expansions of Lorentzian EPRL 4-simplex amplitudes with two different types of boundary states, the coherent intertwiners and the coherent spin-network, and numerically compute the leading-order and the next-to-leading order $O(1/j)$ contributions of these amplitudes. We also study the dependences of these $O(1/j)$ corrections on the Barbero-Immirzi parameter $\gamma$. We show that they, as functions of $\gamma$, stabilize to finite real constants as $\gamma\to\infty$. Lastly, we obtain the quantum corrections to the Regge action because of the $O(1/j)$ contribution to the spinfoam amplitude.

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Muxin Han, Zichang Huang, Hongguang Liu, Dongxue Qu. 2020-07-04. Numerical computations of next-to-leading order corrections in spinfoam large-$j$ asymptotics. https://doi.org/10.1103/physrevd.102.124010

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