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arXiv · 2310.16353

Bound states from the spectral Bethe-Salpeter equation

Abstract

We compute the bound state properties of three-dimensional scalar $\phi^4$ theory in the broken phase. To this end, we extend the recently developed technique of spectral Dyson-Schwinger equations to solve the Bethe-Salpeter equation and determine the bound state spectrum. We employ consistent truncations for the two-, three- and four-point functions of the theory that recover the scaling properties in the infinite coupling limit. Our result for the mass of the lowest-lying bound state in this limit agrees very well with lattice determinations.

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Gernot Eichmann, Andrés Gómez, Jan Horak, Jan M. Pawlowski, Jonas Wessely, Nicolas Wink. 2023-10-25. Bound states from the spectral Bethe-Salpeter equation. https://arxiv.org/abs/2310.16353

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