Migdal-Eliashberg and SUS-$Y^2$-SYK

D. V. Khveshchenko

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arXiv · 2605.31540

Migdal-Eliashberg and SUS-$Y^2$-SYK

D. V. Khveshchenko

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Abstract

This note addresses a number of subtle issues pertaining to the long-standing problem of strong phonon-like fermion-boson coupling. Among the central topics are the customary Migdal-Eliashberg approximation in the pertinent Schwinger-Dyson gap equation and its solutions. The previously gained insight is assessed by contrasting it against the various (non-)supersymmetric variants of the Yukawa-Sachdev-Ye-Kitaev model. Also, some previously discussed (pseudo-)holographic aspects of fermion pairing in such models are commented upon.

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D. V. Khveshchenko. 2026-05-29. Migdal-Eliashberg and SUS-$Y^2$-SYK. https://arxiv.org/abs/2605.31540

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