Physics – High Energy Physics – High Energy Physics - Theory
Scientific paper
2006-06-29
Phys.Lett. B642 (2006) 525-529
Physics
High Energy Physics
High Energy Physics - Theory
Some references have been added. Some points have been clarified
Scientific paper
10.1016/j.physletb.2006.10.009
In absence of matter Einstein gravity with a cosmological constant $\La$ can be formulated as a scale-free theory depending only on the dimensionless coupling constant G \Lambda where G is Newton constant. We derive the conformal field theory (CFT) and its improved stress-energy tensor that describe the dynamics of conformally flat perturbations of the metric. The CFT has the form of a constrained \lambda \phi^{4} field theory. In the cosmological framework the model describes the usual Friedmann-Robertson-Walker flat universe. The conformal symmetry of the gravity sector is broken by coupling with matter. The dimensional coupling constants G and \Lambda are introduced by different terms in this coupling. If the vacuum of quantum matter fields respects the symmetry of the gravity sector, the vacuum energy has to be zero and the ``physical'' cosmological constant is generated by the coupling of gravity with matter. This could explain the tiny value of the observed energy density driving the accelerating expansion of the universe.
No associations
LandOfFree
Conformal symmetry of gravity and the cosmological constant problem does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Conformal symmetry of gravity and the cosmological constant problem, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Conformal symmetry of gravity and the cosmological constant problem will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-598094