Bulk scalar stabilization of the radion without metric back reaction in the Randall-Sundrum model

Apr, 2003
22 pages
Published in:
  • Phys.Rev.D 68 (2003) 055002
e-Print:
Report number:
  • IFT-03-08,
  • UCD-03-03

Citations per year

200320072011201520180123456
Abstract:
Generalizations of the Randall-Sundrum model containing a bulk scalar field Φ\Phi interacting with the curvature RR through the general coupling Rf(Φ)R f(\Phi) are considered. We derive the general form of the effective 4D potential for the spin-zero fields and show that in the mass matrix the radion mixes with the Kaluza-Klein modes of the bulk scalar fluctuations. We demonstrate that it is possible to choose a non-trivial background form Φ0(y)\Phi_0(y) (where yy is the extra dimension coordinate) for the bulk scalar field such that the exact Randall-Sundrum metric is preserved (i.e. such that there is no back-reaction). We compute the mass matrix for the radion and the KK modes of the excitations of the bulk scalar relative to the background configuration Φ0(y)\Phi_0(y) and find that the resulting mass matrix implies a non-zero value for the mass of the radion (identified as the state with the lowest eigenvalue of the scalar mass matrix). We find that this mass is suppressed relative to the Planck scale by the standard warp factor needed to explain the hierarchy puzzle, implying that a mass \sim 1\tev is a natural order of magnitude for the radion mass. The general considerations are illustrated in the case of a model containing an RΦ2R\Phi^2 interaction term.
Note:
  • 22 pages, 3 figures Report-no: UCD-03-03
  • 12.60.Fr
  • 04.50.+h
  • radion: stability
  • Randall-Sundrum model
  • field theory: scalar
  • effective action
  • Kaluza-Klein model
  • mass spectrum
  • background field
  • dimension: 5