{
  "id": "1704.06663",
  "version": "v1",
  "published": "2017-04-21T18:00:09.000Z",
  "updated": "2017-04-21T18:00:09.000Z",
  "title": "A scale at 10 MeV, gravitational topological vacuum, and large extra dimensions",
  "authors": [
    "Ufuk Aydemir"
  ],
  "comment": "7 pages",
  "categories": [
    "hep-ph",
    "gr-qc",
    "hep-th"
  ],
  "abstract": "We discuss a possible scale of gravitational origin at around $10$ MeV, or $10^{-12}$ cm, arisen in the MacDowell-Mansouri formalism of gravity due to the topological Gauss-Bonnet term in the action, proposed by Bjorken several years ago, and named after Zeldovich. A length scale of the same size emerges also in the Kodama solution to gravity, which is known to be closely related to the MacDowell-Mansouri formulation. We particularly draw attention to the intriguing incident that existence of six compact extra dimensions originated from TeV-scale quantum gravity as well points to a length scale of $10^{-12}$ cm, as the compactification scale. The presence of six such extra dimensions is also in remarkable consistency with the MacDowell-Mansouri formalism. In addition, we entertain the idea that a combination of the 'Bjorken-Zeldovich' scale and the TeV-scale, $M_{BZ}^3/M_{EW}^2\\sim 10^{-3}\\mbox{ eV}$, may provide a \"see-saw\" type explanation for the smallness of the cosmological constant and the neutrino mass. We also comment on the relevant implications of such a scale regarding the thermal history of the universe motivated by the fact that it is considerably close to $1-2$ MeV below which the weak interactions freeze out, leading to Big Bang Nucleosynthesis. Recently, an anomaly in Beryllium nuclear transitions at an invariant mass of 17 MeV has been reported. While it is a curious incident that it is at the $10$ MeV scale, whether it has an explanation in this context is currently not manifest.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-04-21T18:00:09.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "large extra dimensions",
      "gravitational topological vacuum",
      "macdowell-mansouri formalism",
      "length scale",
      "compact extra dimensions"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 7,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}