Brans–Dicke Theory and Primordial Black Holes in Early Matter-Dominated Era

Abstract

We show that primordial black holes can be formed in the matter-dominated era with gravity described by the Brans-Dicke theory. Considering an early matter-dominated era between inflation and reheating, we found that the primordial black holes formed during that era evaporate at a quicker rate than those of early radiation-dominated era. Thus, in comparison with latter case, less number of primordial black holes could exist today. Again the constraints on primordial black hole formation tend towards the larger value than their radiation-dominated era counterparts indicating a significant enhancement in the formation of primordial black holes during the matter-dominaed era.PACS numbers: 98.80.-k, 97.60.Lf

Vacuum Energy and Primordial Black Holes in Brans-Dicke Theory

“…Also BD type model can be regarded as the lowest limit of Kaluza-Klein and String theories [7,8,9]. Again BD theory explains many cosmological phenomena such as inflation [10,11], early and late time behaviour of the universe [12,13], cosmic acceleration and structure formation [14], coincidence problem [15] and problems relating to black holes [16].…”

Astrophysical constraints on primordial black holes in Brans-Dicke theory

“…The ubiquitous nature of BD theory is also evident from the fact that it appears in the low energy limit of Kaluza-Klein and String theories [3]. Thus, BD theory has been used for tackling a number of cosmological problems such as inflation [4], early and late time behaviour of the Universe [5], cosmic acceleration and structure formation [6], coincidence problem [7] and problems relating to black holes [8].…”