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arXiv · 2108.03189

On-Shell Recursion Relations for Nonrelativistic Effective Field Theories

Martin A. Mojahed·Tomas Brauner
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Abstract

We derive on-shell recursion relations for nonrelativistic effective field theories (EFTs) with enhanced soft limits. The recursion relations are illustrated through analytic calculation of tree-level scattering amplitudes in theories with a complex Schr\"odinger-type field, real scalar with linear dispersion relation, and real scalar with Lifshitz-type dispersion relation. Our results show that the landscape of gapless nonrelativistic EFTs with local $S$-matrix can be constrained by soft theorems and the consistency of the low-energy $S$-matrix similarly to massless relativistic EFTs.

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Martin A. Mojahed, Tomas Brauner. 2021-08-06. On-Shell Recursion Relations for Nonrelativistic Effective Field Theories. https://doi.org/10.1016/j.physletb.2021.136705

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