2007/10/31 by Jihene Bouchami, J. Bouchami, M. B. Paranjape · 3 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Pulsars and Gravitational Waves Research #astro-ph #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.78.044022
published as Phys.Rev.D78:044022,2008 · 21 pages, 2 figures, colour viewing helpful, version to be published in PRD
arxiv created 2008/06/27 · openalex publication_date 2008/08/11 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study conformal gravity as an alternative theory of gravitation. For conformal gravity to be phenomenologically viable requires that the conformal symmetry is not manifest at the energy scales of the other known physical forces. Hence we are required to find a mechanism for the spontaneous breaking of conformal invariance. In this paper we study the possibility that conformal invariance is spontaneously broken due to interactions with conformally coupled matter fields. The vacuum of the theory admits conformally noninvariant solutions corresponding to maximally symmetric space-times and variants thereof. These are either de Sitter space-time or anti-de Sitter space-time in the full four space-time dimensions and we find new solutions corresponding to maximal symmetry restricted to a lower dimensional subspace. We also consider normalizable, linearized gravitational perturbations around the anti-de Sitter background. We show to second order, that these gravitational fluctuations carry zero energy momentum. Finally we also show the possibility of domain wall solitons interpolating between the ground states of spontaneously broken conformal symmetry that we have found. These solitons necessarily require the vanishing of the scalar field. This offers a way of eschewing the recent suggestion and its consequences [E. Flanagan, Phys. Rev. D 74, 023002 (2006).] that the conformal symmetry could be quarantined to a sterile sector of the theory by choosing an appropriate field redefinition.