Triangle anomalies and nonrelativistic Nambu-Goldstone modes of generalized global symmetries

Noriyuki Sogabe, Naoki Yamamoto

Research output: Contribution to journalArticle


In massless QCD coupled to QED in an external magnetic field, a photon with the linear polarization in the direction of the external magnetic field mixes with the charge neutral pion through the triangle anomaly, leading to one gapless mode with the quadratic dispersion relation ω∼k2 and one gapped mode. We show that this gapless mode can be interpreted as the so-called type-B Nambu-Goldstone (NG) mode associated with the spontaneous breaking of generalized global symmetries and that its presence is solely dictated by the anomalous commutator in the symmetry algebra. We also argue a possible realization of such nonrelativistic NG modes in 3-dimensional Dirac semimetals.

Original languageEnglish
Article number125003
JournalPhysical Review D
Issue number12
Publication statusPublished - 2019 Jun 6


ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this