Explosive phenomena in modified gravity

E. V. Arbuzova, A. D. Dolgov

备注：: 10 pages, 3 figures, version published in PLB, a few references are added and the expression for the frequency of oscillations is corrected
发表信息：: Phys. Lett. B 700, 289-293 (2011)
DOI：: 10.1016/j.physletb.2011.05.030

英文摘要：

Observational manifestations of some models of modified gravity, which have been suggested to explain the accelerated cosmological expansion, are analyzed for gravitating systems with time dependent mass density. It is shown that if the mass density rises with time, the system evolves to the singular state with infinite curvature scalar. The corresponding characteristic time is typically much shorter than the cosmological time.

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