Non-singular Brans-Dicke cosmology with cosmological constant

• Main Authors: Tretyakova, Darya, Shatskiy, Alexander, Novikov, Igor, Alexeyev, Stanislav
• Format: Journal Article
• Language: English
• Published: 02-01-2012
• Subjects: Physics - General Relativity and Quantum Cosmology
• DOI: 10.48550/arxiv.1112.3770

We consider Brans-Dicke cosmology with cosmological constant with negative w
parameter and an arbitrary (in general non-vanishing) scale factor at the Big
Bang. The field equations describe the flat universe, current observational
values for Hubble constant H and deceleration parameter q play a role of
initial conditions. In order to solve field equations we adopt the approach of
Uehara and Kim (1982). They considered only positive values of w, hence our
solution is a new one and has not been described in their paper. Our main
result is that unlike the standard cosmology the scale factor may not vanish in
it's evolution back in time. In other words our model displays a cosmological
bounce and avoids the initial singularity. The formula for the scale factor,
leading to the bounce, is only valid for the dust-filled universe and hence
cannot be adequate for the hot stage in the early universe when the bounce
happens. So, the results of this paper are only qualitative in nature and must
be used to obtain initial values for the hot stage of the unverse when one
considers the evolution back in time.