Spacetime expansion in the presence of a background velocity field
Department of Physics, University of Guilan, 41335-1914, Rasht, Iran
Accepted: 14 November 2021
Published online: 23 November 2021
In this article, we introduce a new metric assuming an additional velocity-based term in a spacetime metric. Although the inclusion of this additional phrase can indicate that the Lorentz symmetry has broken, the results of null geodesics demonstrate that the amount of variation in the speed of light is considerably smaller than what can be observed. This article delves into the primary use of this additional phrase in the expansion development of Minkowski and de Sitter spacetimes. The findings indicate that multiple versions of the velocity function may explain the universe’s initial explosion and expansion behavior even before the inflation epoch, the inflation itself, and the universe’s positive acceleration in late-time cosmology without dark matter or dark energy. These models can also rebuild primordial black holes in the early universe as an alternative to dark matter.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2021