English

On relevance of modified gravities

General Relativity and Quantum Cosmology 2011-05-26 v3 Mathematical Physics math.MP

Abstract

It is shown that modified gravity theories with a Lagrangian composed of the three quadratic invariants of the Riemann curvature tensor are not appropriate. The field equations are either incompatible and/or irregular [like f(R)-gravities], or, if compatible, lead to the linear instability of polarizations relating to the Weyl tensor. A more relevant modification is the frame field theory, namely the best and unique variant of Absolute Parallelism; it has no free parameters (D=5 is a must) and no singularities arising in solutions. I sketch few remarkable features of this theory.

Keywords

Cite

@article{arxiv.0812.1344,
  title  = {On relevance of modified gravities},
  author = {I. L. Zhogin},
  journal= {arXiv preprint arXiv:0812.1344},
  year   = {2011}
}

Comments

Submitted to the Zelmanov Journal; 11 pages; improvements and new issues: (trivial) `weak' Lagrangian (term of N.Kh. Ibragimov) and classification of AP polarizations