{
  "id": "1205.3761",
  "version": "v2",
  "published": "2012-05-16T19:00:53.000Z",
  "updated": "2012-07-11T15:46:14.000Z",
  "title": "Spontaneous symmetry breaking in inflationary cosmology: on the fate of Goldstone Bosons",
  "authors": [
    "Daniel Boyanovsky"
  ],
  "comment": "32 pages, 6 figures",
  "journal": "Phys. Rev. D 86, 023509 (2012)",
  "doi": "10.1103/PhysRevD.86.023509",
  "categories": [
    "astro-ph.CO",
    "gr-qc",
    "hep-ph",
    "hep-th"
  ],
  "abstract": "We argue that in an inflationary cosmology a consequence of the lack of time translational invariance is that spontaneous breaking of a continuous symmetry and Goldstone's theorem \\emph{do not} imply the existence of \\emph{massless} Goldstone modes. We study spontaneous symmetry breaking in an O(2) model, and implications for O(N) in de Sitter space time. The Goldstone mode acquires a radiatively generated mass as a consequence of infrared divergences, and the continuous symmetry is spontaneously broken for any finite $N$, however there is a \\emph{first order phase transition} as a function of the Hawking temperature $T_H=H/2\\pi$. For O(2) the symmetry is spontaneously broken for $T_H < T_c= \\lambda^{1/4} v/2.419$ where $\\lambda$ is the quartic coupling and $v$ is the tree level vacuum expectation value and the Goldstone mode acquires a radiatively generated mass $\\mathcal{M}^2_\\pi \\propto \\lambda^{1/4} H$. The first order nature of the transition is a consequence of the strong infrared behavior of minimally coupled scalar fields in de Sitter space time, the jump in the order parameter at $T_H=T_c$ is $\\sigma_{0c} \\simeq 0.61\\, {H}/{\\lambda^{1/4}}$. In the strict $N\\rightarrow \\infty$ the symmetry cannot be spontaneously broken. Furthermore, the lack of kinematic thresholds imply that the Goldstone modes \\emph{decay} into Goldstone and Higgs modes by emission and absorption of superhorizon quanta.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2012-07-11T15:46:14.000Z"
    }
  ],
  "analyses": {
    "subjects": [
      "11.10.-z",
      "98.80.-k",
      "98.80.Cq"
    ],
    "keywords": [
      "spontaneous symmetry breaking",
      "inflationary cosmology",
      "goldstone bosons",
      "sitter space time",
      "goldstone mode acquires"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "publisher": "APS",
      "journal": "Physical Review D",
      "year": 2012,
      "month": "Jul",
      "volume": 86,
      "number": 2,
      "pages": "023509"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 32,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1114954,
      "adsabs": "2012PhRvD..86b3509B"
    }
  }
}