32 citations · 188 across the 17 of their papers we have counts for
8 papers · 1 filter
Induced Gravitational Waves from Ultra Slow-Roll Inflation and Pulsar Timing Arrays Observations
Hassan Firouzjahi, Alireza Talebian
The stochastic gravitational wave background (SGWB) detected recently by the pulsar timing arrays (PTAs) observations may have cosmological origins. In this work we consider a mode…
White Hole Cosmology and Hawking Radiation from Quantum Cosmological Perturbations
Hassan Firouzjahi, Alireza Talebian
The spacetime inside the white hole is like an anisotropic cosmological background with the past singularity playing the role of a big bang singularity. The scale factor along the…
Dark Matter from Entropy Perturbations in Curved Field Space
Hassan Firouzjahi, Mohammad Ali Gorji, Shinji Mukohyama +1
The accumulated energy density of the excited entropy modes in multiple field inflationary scenarios can play the role of dark matter. In the usual case of a flat field space witho…
Multi-field Mimetic Gravity
Seyed Ali Hosseini Mansoori, Alireza Talebian, Zahra Molaee +1
In this paper, we extend the mimetic gravity to the multi-field setup with a curved field space manifold. The multi-field mimetic scenario is realized via the singular limit of the…
Mimetic Inflation
Seyed Ali Hosseini Mansoori, Alireza Talebian, Hassan Firouzjahi
We study inflationary solution in an extension of mimetic gravity with the higher derivative interactions coupled to gravity. Because of the higher derivative interactions, the set…
Revisiting Magnetogenesis during Inflation
Alireza Talebian, Amin Nassiri-Rad, Hassan Firouzjahi
We revisit the mechanism of primordial magnetogenesis during inflation by taking into account the dynamics of the stochastic noises of the electromagnetic perturbations. We obtain…
Black Hole Superradiance in f(R) Gravities
Mohsen Khodadi, Alireza Talebian, Hassan Firouzjahi
We study the superradiance amplification factor (SAF) for a charged massive scalar wave scattering off small and slowly rotating Kerr-Newman black holes in gravity immersed…
Stochastic Effects in Anisotropic Inflation
Alireza Talebian, Amin Nassiri-Rad, Hassan Firouzjahi
We revisit the stochastic effects in the model of anisotropic inflation containing a gauge field. We obtain the Langevin equations for the inflaton and gauge fields perturba…