English

Ward identities for strongly coupled Eliashberg theories

Strongly Correlated Electrons 2016-08-31 v1

Abstract

We discuss Ward identities for strongly interacting fermion systems described by Eliashberg-type theories. We show that Ward identities are not in conflict with Migdal theorem. We derive diagrammatically Ward identity for a charge vertex in a Fermi liquid, and when a Fermi liquid is destroyed at quantum criticality. We argue that Ward identity for a spin vertex cannot be obtained within Eliashberg theory.

Keywords

Cite

@article{arxiv.cond-mat/0411039,
  title  = {Ward identities for strongly coupled Eliashberg theories},
  author = {Andrey V. Chubukov},
  journal= {arXiv preprint arXiv:cond-mat/0411039},
  year   = {2016}
}

Comments

7 pages, 4 figures