608 K 19 pp. | ||

View Document | ||

Title | Instantons and Massless Fermions in Two Dimensions | |

Author(s) | Callan, C. G. Jr.; Dashen, R.; Gross, D. J. | |

Publication Date | May 1977 | |

Report Number | COO-2220-110 | |

Unique Identifier | ACC0469 | |

Other Numbers | OSTI ID: 7284867 | |

Research Org | Institute for Advanced Study, Princeton, N.J. (USA); Princeton University, N.J. (USA). Joseph Henry Laboratories | |

Contract No | EY-76-S-02-2220 | |

Sponsoring Org | Energy Research and Development Administration (ERDA) | |

Subject | 72 Physics of Elementary Particles and Fields; Chiral Symmetry; Symmetry Breaking; U Groups; Fermions; Four-Dimensional Calculations; Goldstone Bosons; Two-Dimensional Calculations; U-1 Groups; Vectors; Bosons; Elementary Particles; Lie Groups; Postulated Particles; Symmetry; Symmetry Groups; Tensors | |

Related Web Pages | David J. Gross and the Strong Force | |

Abstract | The role of instantons in the breakdown of chiral U(N) symmetry is studied in a two dimensional model. Chiral U(1) is always destroyed by the axial vector anomaly. For N = 2 chiral SU(N) is also spontaneously broken yielding massive fermions and three (decoupled) Goldstone bosons. For N greater than or equal to 3 the fermions remain massless. Realistic four dimensional theories are believed to behave in a similar way but the critical N above which the fermions cease to be massive is not known in four dimensions. | |

608 K 19 pp. | ||

View Document | ||