  
  
Stat 
Members: 3660 Articles: 2'599'751 Articles rated: 2609
10 November 2024 

   

Article overview
 

Primordial black hole formation in $F(R)$ bouncing cosmology  Shreya Banerjee
; Theodoros Papanikolaou
; Emmanuel N. Saridakis
;  Date: 
2 Jun 2022  Abstract:  The phenomenology of primordial black holes (PBHs) physics, and the
associated PBH abundance constraints, can be used in order to probe the
earlyuniverse evolution. In this work, we focus on the bounce realization
within $F(R)$ modified gravity and we investigate the corresponding PBH
behavior. In particular, we calculate the energy density power spectrum at
horizon crossing time as a function of the involved theoretical parameters, and
then we extract the PBH abundance in the context of peak theory, considering
the nonlinear relation between the density contrast and the comoving curvature
perturbation, as well as the critical collapse law for the PBH masses. We first
calculate the PBH mass function, and then we extract the PBH abundance
$Omega_mathrm{PBH,f}$ at formation time as a function of the model
parameters, namely the involved $F(R)$ parameter $alpha$ and the Hubble
parameter at the transition time from the bounce to the radiation dominated
epoch $H_mathrm{RD}$. Interestingly, we find that in order to have a
significant black hole production, namely $10^{10}<Omega_mathrm{PBH,f}<1$,
$H_mathrm{RD}$ and $alpha$ should lie roughly within the ranges
$10^{7}M_mathrm{Pl}leq H_mathrm{RD}leq 10^{6}M_mathrm{Pl}$,
$10^{9}M_mathrm{Pl}leq H_mathrm{RD}leq 2 imes 10^{9}M_mathrm{Pl}$ and
$10^{30}M^2_mathrm{Pl}leq alpha leq 10^{12}M^2_mathrm{Pl}$ respectively.
Finally, we show that the excluded region corresponding to PBH overproduction
forms a closed ring.  Source:  arXiv, 2206.01150  Services:  Forum  Review  PDF  Favorites 


No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.

 


