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arXiv · 2307.14727

Self-adjointness and domain of generalized spin-boson models with mild ultraviolet divergences

Sascha Lill·Davide Lonigro
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Abstract

We provide a rigorous construction of a large class of generalized spin-boson models with ultraviolet-divergent form factors. This class comprises various models of many possibly non-identical atoms with arbitrary but finite numbers of levels, interacting with a boson field. Ultraviolet divergences are assumed to be mild, such that no self-energy renormalization is necessary. Our construction is based on recent results by A. Posilicano, which also allow us to state an explicit formula for the domain of self-adjointness for our Hamiltonians.

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Sascha Lill, Davide Lonigro. 2023-07-27. Self-adjointness and domain of generalized spin-boson models with mild ultraviolet divergences. https://doi.org/10.1007/978-981-96-3584-9_7

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