Large-n Gauge Theories: Lattice Perspectives and Conjectures

  • M. TEPER
  • Published 2004

Abstract

It is 30 years since it was proposed that it might be useful to think of QCD as a perturbation in 1/N around the N = ∞ theory . As is apparent from the talks at this meeting, this has been a very fruitful idea . However we still do not have a quantitative control of the SU(N = ∞) theory and the phenomenology needs to assume, for example, that it is confining and, of course, ‘close to’ SU(3). Lattice simulations can attempt to answer such questions directly (albeit never exactly) and there has been substantial progress in doing so this last decade, first in D=2+1 dimensions , which I do not discuss here, and then in the physically interesting case of D=3+1. (For a review of work in the earlier 80’s, when lattice calculations were not yet precise enough to be so useful, see e.g. .) Here I focus on what these ‘modern’ lattice calculations teach us about the properties of SU(N) gauge theories at large N . I will begin with some motivation for these calculations. A gluon loop on a gluon propagator comes with a factor of gN . One easily sees that g is in fact the smallest power of the coupling that comes with a factor of N . So if one wants an N → ∞ limit that is not given by either a free field theory or by infinite order diagrams on all length scales (in

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Cite this paper

@inproceedings{TEPER2004LargenGT, title={Large-n Gauge Theories: Lattice Perspectives and Conjectures}, author={M. TEPER}, year={2004} }