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arxiv: 1807.03066 · v3 · pith:V2WS3YGWnew · submitted 2018-07-09 · 🌀 gr-qc

Numerical methods for EPRL spin foam transition amplitudes and Lorentzian recoupling theory

classification 🌀 gr-qc
keywords eprllorentzianamplitudeamplitudesfoammathbbspintransition
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The intricated combinatorial structure and the non-compactness of the Lorentz group have always made the computation of $SL(2,\mathbb{C})$ EPRL spin foam transition amplitudes a very hard and resource demanding task. With \texttt{sl2cfoam} we provide a C-coded library for the evaluation of the Lorentzian EPRL vertex amplitude. We provide a tool to compute the Lorentzian EPRL 4-simplex vertex amplitude in the intertwiner basis and some utilities to evaluate SU(2) invariants, booster functions and $SL(2,\mathbb{C})$ Clebsch-Gordan coefficients. We discuss the data storage, parallelizations, time, and memory performances and possible future developments.

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