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Hidden Quantum Gravity in 4d Feynman diagrams: Emergence of spin foams

Aristide Baratin·Laurent Freidel
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Abstract

We show how Feynman amplitudes of standard QFT on flat and homogeneous space can naturally be recast as the evaluation of observables for a specific spin foam model, which provides dynamics for the background geometry. We identify the symmetries of this Feynman graph spin foam model and give the gauge-fixing prescriptions. We also show that the gauge-fixed partition function is invariant under Pachner moves of the triangulation, and thus defines an invariant of four-dimensional manifolds. Finally, we investigate the algebraic structure of the model, and discuss its relation with a quantization of 4d gravity in the limit where the Newton constant goes to zero.

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Aristide Baratin, Laurent Freidel. 2007-03-28. Hidden Quantum Gravity in 4d Feynman diagrams: Emergence of spin foams. https://doi.org/10.1088/0264-9381%2F24%2F8%2F007

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