Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-10-31
Phys.Rev.D79:024009,2009
Astronomy and Astrophysics
Astrophysics
9 pages, 9 figures, v2: minor modifications, version accepted for publication in Phys. Rev. D
Scientific paper
10.1103/PhysRevD.79.024009
Although $f(R)$ modified gravity models can be made to satisfy solar system and cosmological constraints, it has been shown that they have the serious drawback of the nonexistence of stars with strong gravitational fields. In this paper, we discuss whether or not higher curvature corrections can remedy the nonexistence consistently. The following problems are shown to arise as the costs one must pay for the $f(R)$ models that allow for neutrons stars: (i) the leading correction must be fine-tuned to have the typical energy scale $\mu \lesssim 10^{-19}$ GeV, which essentially comes from the free fall time of a relativistic star; (ii) the leading correction must be further fine-tuned so that it is not given by the quadratic curvature term. The second problem is caused because there appears an intermediate curvature scale and laboratory experiments of gravity will be under the influence of higher curvature corrections. Our analysis thus implies that it is a challenge to construct viable $f(R)$ models without very careful and unnatural fine-tuning.
Kobayashi Tsutomu
Maeda Kei--ichi
No associations
LandOfFree
Can higher curvature corrections cure the singularity problem in f(R) gravity? 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 Can higher curvature corrections cure the singularity problem in f(R) gravity?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Can higher curvature corrections cure the singularity problem in f(R) gravity? will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-456912