1998/06/12 by J. C. Fabris, Richard Kerner, R. Kerner +1
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #gr-qc
paper · pdf · doi:10.1142/s0218271800000116
published as Int.J.Mod.Phys. D9 (2000) 111-125 · 14 pages, Latex file
arxiv created 1998/06/12 · openalex publication_date 2000/04/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The hypothesis that the energy–momentum tensor of ordinary matter is not conserved separately, leads to a nonadiabatic expansion and, in many cases, to an Universe older than usual. This may provide a solution for the entropy and age problems of the Standard Cosmological Model. We consider two different theories of this type, and we perform a perturbative analysis, yielding analytical expressions for the evolution of gravitational waves, rotational modes and density perturbations. One of these theories exhibits satisfactory properties at this level, while the other one should be discarded.