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arXiv · 2310.20596

Local solutions of RG flow equations from the Nash-Moser theorem

Edoardo D'Angelo·Nicola Pinamonti
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Abstract

We prove local existence of solutions of a functional Renormalisation Group equation for the effective action of an interacting quantum field theory, when a suitable Local Potential Approximation is considered. To obtain this equation in a Lorentzian setting, a quantum state for the theory is selected, and a regulator consisting in a mass is added to the action. The flow equation for mass rescalings is then studied using the renown Nash-Moser theorem.

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Edoardo D'Angelo, Nicola Pinamonti. 2023-10-31. Local solutions of RG flow equations from the Nash-Moser theorem. https://arxiv.org/abs/2310.20596

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