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arXiv · 2401.07130

On the interplay between boundary conditions and the Lorentzian Wetterich equation

Claudio Dappiaggi·Filippo Nava·Luca Sinibaldi
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Abstract

In the framework of the functional renormalization group and of the perturbative, algebraic approach to quantum field theory (pAQFT), in [DDPR23] it has been derived a Lorentian version of a flow equation \`a la Wetterich, which can be used to study non linear, quantum scalar field theories on a globally hyperbolic spacetime. In this work we show that the realm of validity of this result can be extended to study interacting scalar field theories on globally hyperbolic manifolds with a timelike boundary. By considering the specific examples of half Minkowski spacetime and of the Poincar\'e patch of Anti-de Sitter, we show that the form of the Lorentzian Wetterich equation is strongly dependent on the boundary conditions assigned to the underlying field theory. In addition, using a numerical approach, we are able to provide strong evidences that there is a qualitative and not only a quantitative difference in the associated flow and we highlight this feature by considering Dirichlet and Neumann boundary conditions on half Minkowski spacetime.

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Claudio Dappiaggi, Filippo Nava, Luca Sinibaldi. 2024-01-13. On the interplay between boundary conditions and the Lorentzian Wetterich equation. https://arxiv.org/abs/2401.07130

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