{
  "id": "hep-th/0603041",
  "version": "v2",
  "published": "2006-03-06T16:47:32.000Z",
  "updated": "2006-05-15T07:30:49.000Z",
  "title": "Theta-dependence of the spectrum of SU(N) gauge theories",
  "authors": [
    "Luigi Del Debbio",
    "Gian Mario Manca",
    "Haralambos Panagopoulos",
    "Apostolos Skouroupathis",
    "Ettore Vicari"
  ],
  "comment": "16 pages, 3 figures. Some clarifications included, final version published in JHEP",
  "journal": "JHEP 0606:005,2006",
  "doi": "10.1088/1126-6708/2006/06/005",
  "categories": [
    "hep-th",
    "hep-lat"
  ],
  "abstract": "We study the theta dependence of the spectrum of four-dimensional SU(N) gauge theories, where theta is the coefficient of the topological term in the Lagrangian, for N>=3 and in the large-N limit. We compute the O(theta^2) terms of the expansions around theta=0 of the string tension and the lowest glueball mass, respectively sigma(theta) = sigma (1 + s_2 theta^2 + ...) and M(theta) = M (1 + g_2 theta^2 + ...), where sigma and M are the values at theta=0. For this purpose we use numerical simulations of the Wilson lattice formulation of SU(N) gauge theories for N=3,4,6. The O(theta^2) coefficients turn out to be very small for all N>=3. For example, s_2=-0.08(1) and g_2=-0.06(2) for N=3. Their absolute values decrease with increasing N. Our results are suggestive of a scenario in which the theta dependence in the string and glueball spectrum vanishes in the large-N limit, at least for sufficiently small values of |theta|. They support the general large-N scaling arguments that indicate (theta/N) as the relevant Lagrangian parameter in the large-N expansion.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2006-05-15T07:30:49.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "gauge theories",
      "large-n limit",
      "theta-dependence",
      "theta dependence",
      "general large-n scaling arguments"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "IOP",
      "journal": "J. High Energ. Phys."
    },
    "note": {
      "typesetting": "TeX",
      "pages": 16,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 711791
    }
  }
}