On discrete anomalies in chiral gauge theories
Philip Boyle Smith, Avner Karasik, Nakarin Lohitsiri, David Tong
Abstract
A bstract We study two well-known SU( N ) chiral gauge theories with fermions in the symmetric, anti-symmetric and fundamental representations. We give a detailed description of the global symmetry, including various discrete quotients. Recent work argues that these theories exhibit a subtle mod 2 anomaly, ruling out certain phases in which the theories confine without breaking their global symmetry, leaving a gapless composite fermion in the infra-red. We point out that no such anomaly exists. We further exhibit an explicit path to the gapless fermion phase, showing that there is no kinematic obstruction to realising these phases.
Topics & Concepts
PhysicsAnomaly (physics)Gauge anomalyChiral anomalyTheoretical physicsGapless playbackGauge theoryFermionChiral symmetry breakingGlobal symmetrySupersymmetric gauge theoryMixed anomalyGauge (firearms)Symmetry (geometry)Mathematical physicsSpontaneous symmetry breakingSymmetry breakingQuantum mechanicsGeometryMathematicsArchaeologyHistoryCondensed matter physicsBlack Holes and Theoretical PhysicsQuantum Chromodynamics and Particle InteractionsParticle physics theoretical and experimental studies