| Domaine : |
 |
|
|
| Titre : |
|
Lorentz-violating vs. ghost gravitons: the example of Weyl gravity |
|
| Auteur(s) : |
|
N. Deruelle1, M. Sasaki2, Y. Sendouda1, A. Youssef |
|
| Laboratoire : |
|
|
|
| équipe(s) de recherche : |
|
APC - THEORIE |
| Résumé : |
|
We show that the ghost degrees of freedom of Einstein gravity with a Weyl term can be tamed by a simple mechanism that invokes local Lorentz symmetry breaking. We demonstrate how the mechanism works in a cosmological setting. The presence of the Weyl term forces a redefinition of the quantum vacuum state of the tensor perturbations. As a consequence the amplitude of their spectrum blows up when the Lorentz-violating scale becomes comparable to the Hubble radius. Such a behaviour is in sharp contrast to what happens in standard Weyl gravity where the gravitational ghosts smoothly damp out the spectrum of primordial gravitational waves. |
|
Langue du texte
intégral : |
|
Anglais |
|
Date de production,
écriture : |
|
14/02/2012 |
|
|
| Journal : |
|
| Journal of High Energy Physics |
| Publisher |
Institute of Physics (IOP) |
| ISSN |
1126-6708 (eISSN : 1029-8479) |
|
|
| Audience : |
|
internationale |
|
| Type de publication : |
|
Articles dans des revues avec comité de lecture |
|
| Date de publication : |
|
09/2012 |
|
| Volume : |
|
09 |
|
| Page, identifiant, ... : |
|
009 |
|
|
| Mots Clés : |
|
Cosmology of Theories beyond the SM – Models of Quantum Gravity – Classical Theories of Gravity |
|
| Commentaire : |
|
14 pages, 3 figures, REVTeX 4.1 |
|
|
Récupérer au format
