Asymptotics of LQG fusion coefficients

Abstract

The fusion coefficients from SO(3) to SO(4) play a key role in the definition of spin foam models for the dynamics in Loop Quantum Gravity. In this paper we give a simple analytic formula of the EPRL fusion coefficients. We study the large spin asymptotics and show that they map SO(3) semiclassical intertwiners into $SU(2{)}_L\times SU(2{)}_R$ semiclassical intertwiners. This non-trivial property opens the possibility for an analysis of the semiclassical behavior of the model.

14 pages, minor changes

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Cited by in corpus (11)

• The Spin Foam Approach to Quantum Gravity
• LQG propagator from the new spin foams
• Self-energy and vertex radiative corrections in LQG
• Operator Spin Foam Models
• Spinfoams in the holomorphic representation
• A regularization of the hamiltonian constraint compatible with the spinfoam dynamics
• Coherent states for FLRW space-times in loop quantum gravity
• Intertwiner dynamics in the flipped vertex
• A Short and Subjective Introduction to the Spinfoam Framework for Quantum Gravity
• The new spin foam models and quantum gravity
• Evaluation of new spin foam vertex amplitudes