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arXiv · 2208.07383

Local Neumann semitransparent layers: resummation, pair production and duality

N. Ahmadiniaz·S. A. Franchino-Viñas·L. Manzo·F. D. Mazzitelli
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Abstract

We consider local semitransparent Neumann boundary conditions for a quantum scalar field as imposed by a quadratic coupling to a source localized on a flat codimension-one surface. Upon a proper regularization to give meaning to the interaction, we interpret the effective action as a theory in a first-quantized phase space. We compute the relevant heat-kernel to all order in a homogeneous background and to quadratic order in perturbations, giving a closed expression for the corresponding effective action in $D=4$. In the dynamical case, we analyze the pair production caused by a harmonic perturbation and by a Sauter pulse. Notably, we prove the existence of a strong/weak duality that links this Neumann field theory to the analogue Dirichlet one.

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N. Ahmadiniaz, S. A. Franchino-Viñas, L. Manzo, F. D. Mazzitelli. 2022-08-15. Local Neumann semitransparent layers: resummation, pair production and duality. https://doi.org/10.1103/physrevd.106.105022

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