Zobrazeno 1 - 10
of 54
pro vyhledávání: '"Farhang, Marzieh"'
In this study, we investigate the impact of modified gravity on the merger rate of compact binaries within dark-matter spikes surrounding super-massive black holes (SMBHs). Specifically, we calculate binary merger rates involving primordial black hol
Externí odkaz:
http://arxiv.org/abs/2408.11995
We explore the possibility of redshift-dependent deviations in the contribution of relativistic degrees of freedom to the radiation budget of the cosmos, conventionally parameterized by the effective number of neutrinos $N_{\rm eff}$, from the predic
Externí odkaz:
http://arxiv.org/abs/2404.01457
Publikováno v:
The Astrophysical Journal (2024)
In this work we investigate the merger rate of primordial black hole-neutron star (PBH-NS) binaries in two widely-studied modified gravity (MG) models: Hu-Sawicki $f(R)$ gravity and the normal branch of Dvali-Gabadadze-Porrati (nDGP) gravity. In our
Externí odkaz:
http://arxiv.org/abs/2401.15171
Autor:
Safi, Sarah, Farhang, Marzieh
Publikováno v:
ApJ 965 4 (2024)
Several ongoing and upcoming large scale structure surveys aim to explore the nonlinear regime of structure formation with high precision. Making reliable cosmological inferences from these observations necessitates precise theoretical modeling of th
Externí odkaz:
http://arxiv.org/abs/2312.07068
Publikováno v:
Physics of the Dark Universe (2024)
Ultradense dark matter halos (UDMHs) are high concentrations of dark matter, assumed to have formed deep in the radiation-dominated era from amplified primordial perturbations. In this work we improve the previous works for the calculation of UDMH ab
Externí odkaz:
http://arxiv.org/abs/2311.15307
Autor:
Farhang, Marzieh, Khosravi, Nima
In this work we extend our earlier phenomenological model for a gravitational phase transition (GPT) and its generalization to early times by letting the modifications in the linearly-perturbed Einstein equations be scale-dependent. These modificatio
Externí odkaz:
http://arxiv.org/abs/2306.14014
Publikováno v:
In Physics of the Dark Universe December 2024 46
In this work we explore the possibility of variations in the primordial scalar power spectrum around the power-law shape, as predicted by single-field slow-roll inflationary scenarios. We search for the trace of these fluctuations in a semi-blind, mo
Externí odkaz:
http://arxiv.org/abs/2109.12807
Autor:
Khosravi, Nima, Farhang, Marzieh
In this work we generalize the idea of a gravitational phase transition or GPT at late times to allow for a modified gravity scenario in the early universe as well. The original GPT was shown to simultaneously relax the $H_0$ and $\sigma_8$ tensions
Externí odkaz:
http://arxiv.org/abs/2109.10725
Autor:
Safi, Sarah, Farhang, Marzieh
Publikováno v:
Astrophys.J. 914 (2021) 1, 65
Next generation large scale surveys probe the nonlinear regime with high resolution. Making viable cosmological inferences based on these observations requires accurate theoretical modeling of the mildly nonlinear regime. In this work we investigate
Externí odkaz:
http://arxiv.org/abs/2012.11526