32 citations · 188 across the 17 of their papers we have counts for
17 papers
Models with Non-minimal Coupling in Primordial Universe and Cosmological Observations
Alireza Talebian, Hassan Firouzjahi, Fereshteh Felegary
A non-minimal coupling between gravity and the inflaton field is a generic contribution in inflationary cosmology. In this work, we consider models of inflation with a non-minimal…
Axion USR Inflation
Alireza Talebian, Hassan Firouzjahi
We consider a model of inflation in which the inflaton field is a rolling axion with a potential which is flat enough to support an intermediate phase of USR inflation. Because of…
Early Dark Energy and Dark Photon Dark Matter from Waterfall Symmetry Breaking
Alireza Talebian
We investigate a cosmological model wherein a waterfall symmetry breaking occurs during the radiation-dominated era. The model comprises a complex waterfall field, an axion field,…
Revisiting the stochastic QCD axion window: departure from equilibrium during inflation
Vadim Briaud, Kenji Kadota, Shinji Mukohyama +2
If dark matter is made of QCD axions, its abundance is determined by the vacuum expectation value acquired by the axion field during inflation. The axion is usually assumed to foll…
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…
Inflation from Multiple Pseudo-Scalar Fields: PBH Dark Matter and Gravitational Waves
Alireza Talebian, Seyed Ali Hosseini Mansoori, Hassan Firouzjahi
We study a model of inflation with multiple pseudo-scalar fields coupled to a gauge field through Chern-Simons interactions. Because of parity violating interactions, one po…
Multiple transitions in vacuum dark energy and tension
Hossein Moshafi, Hassan Firouzjahi, Alireza Talebian
We study the effects of multiple transitions in the vacuum dark energy density on the tension problem. We consider a phenomenological model in which the vacuum energy density…
Stochastic Effects in Axion Inflation and Primordial Black Holes Formation
Alireza Talebian, Amin Nassiri-Rad, Hassan Firouzjahi
We revisit the model of axion inflation in the context of stochastic inflation and investigate the effects of the stochastic noises associated to the electromagnetic fields. Becaus…
Multiple Field Ultra Slow Roll Inflation: Primordial Black Holes From Straight Bulk And Distorted Boundary
Sina Hooshangi, Alireza Talebian, Mohammad Hossein Namjoo +1
We study a model of two-field ultra-slow-roll (USR) inflation bounded by a curve in the field space. Curvature perturbations and non-Gaussianities can be enhanced both during the U…
Primordial Helical Magnetic Fields from Inflation?
Alireza Talebian, Amin Nassiri-Rad, Hassan Firouzjahi
We revisit the mechanism of helical magnetogenesis during inflation with a parity violating interaction using the formalism of stochastic inflation. One of the polarization of 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…