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arXiv · 2102.06425

Vacuum energy for a scalar field with self-interaction in (1+1) dimensions

M. Bordag
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Abstract

We calculate the vacuum (Casimir) energy for a scalar field with $ϕ^4$ self-interaction in (1+1) dimensions non perturbatively, i.e., in all orders of the self-interaction. We consider massive and massless fields in a finite box with Dirichlet boundary conditions and on the whole axis as well. For strong coupling, the vacuum energy is negative indicating some instability.

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M. Bordag. 2021-02-12. Vacuum energy for a scalar field with self-interaction in (1+1) dimensions. https://arxiv.org/abs/2102.06425

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