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arXiv · 2402.12985

Lüscher equation with long-range forces

Rishabh Bubna·Hans-Werner Hammer·Fabian Müller·Jin-Yi Pang·Akaki Rusetsky·Jia-Jun Wu
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Abstract

We derive the modified Lüscher equation in the presence of the long-range force caused by the exchange of a light particle. It is shown that the use of this equation enables one to circumvent the problems related to the strong partial-wave mixing and the t-channel sub-threshold singularities. It is also demonstrated that the present method is intrinsically linked to the so-called modified effective-range expansion (MERE) in the infinite volume. A detailed comparison with the two recently proposed alternative approaches is provided.

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Rishabh Bubna, Hans-Werner Hammer, Fabian Müller, Jin-Yi Pang, Akaki Rusetsky, Jia-Jun Wu. 2024-04-24. Lüscher equation with long-range forces. https://arxiv.org/abs/2402.12985

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