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arXiv · 2206.14755

Radiative corrections to the Lorentzian EPRL spin foam propagator

Pietro Donà·Pietropaolo Frisoni·Edward Wilson-Ewing
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Abstract

We numerically estimate the divergence of several two-vertex diagrams that contribute to the radiative corrections for the Lorentzian EPRL spin foam propagator. We compute the amplitudes as functions of a homogeneous cutoff over the bulk quantum numbers, fixed boundary data, and different Immirzi parameters, and find that for a class of two-vertex diagrams, those with fewer than six internal faces are convergent. The calculations are done with the numerical framework sl2cfoam-next.

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Pietro Donà, Pietropaolo Frisoni, Edward Wilson-Ewing. 2022-11-03. Radiative corrections to the Lorentzian EPRL spin foam propagator. https://doi.org/10.1103/physrevd.106.066022

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