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arXiv · 2208.10632

Coherent States and Particle Scattering in Loop Quantum Gravity

Deepak Vaid·Devadharshini Suresh
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Abstract

Quantum field theory provides us with the means to calculate scattering amplitudes. In recent years a dramatic new development has lead to great simplification of such calculations. This is based on the discovery of the``amplituhedron'' in the context of scattering of massless gauge bosons in Yang-Mills theory. One of the main challenges facing Loop Quantum Gravity is the lack of a clear description of particle scattering processes and a connection to flat space QFT. Here we show a correspondence between the space of kinematic data of the scattering $ N $ massless particles and $ U(N) $ coherent states in LQG. This correspondence allows us to provide the outlines of a theory of quantum gravity based upon the dynamics of excitations living on the the positive Grassmannian.

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Deepak Vaid, Devadharshini Suresh. 2022-08-18. Coherent States and Particle Scattering in Loop Quantum Gravity. https://doi.org/10.1140/epjc%2Fs10052-022-10701-6

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