28 citations · 112 across the 13 of their papers we have counts for
13 papers
On the constant roll complex scalar field inflationary models
Ali Mohammadi, Nahid Ahmadi, Mehdi Shokri
In this paper we wish to point out the possibility of using a complex scalar field in a constant roll inflationary model, as needed for observational viability. We extend the idea…
Quantum Diffusion in Sharp Transition to Non-Slow-Roll Phase
Nahid Ahmadi, Mahdiyar Noorbala, Niloufar Feyzabadi +2
Transitions between different inflationary slow-roll scenarios are known to provide short non-slow-roll periods with non-trivial consequences. We consider the effect of quantum dif…
\bf Formalism and Anisotropic Chaotic Inflation Power Spectrum
Alireza Talebian-Ashkezari, Nahid Ahmadi
A new analytical approach to linear perturbations in anisotropic inflation has been introduced in [A. Talebian-Ashkezari, N. Ahmadi and A.A. Abolhasanib, JCAP 03(2018)001] under th…
\bf Formalism: A New Approach to Cosmological Perturbation Theory in Anisotropic Inflation
Alireza Talebian-Ashkezari, Nahid Ahmadi, Ali Akbar Abolhasani
We study the evolution of the metric perturbations in a Bianchi background in the long-wavelength limit. By applying the gradient expansion to the equations of motion we exhibit a…
Deflection of light by the field of a binary system
Nahid Ahmadi, Zainab Sedaghatmanesh
We examine the motion of a photon in the gravitational field of a binary system. The equations of motion are geodesic equations in a Schwarzchild background with a tidal force. We…
Can non-local or higher derivative theories provide alternatives to inflation?
Ghazal Geshnizjani, Nahid Ahmadi
The standard mechanism for producing the observed scale-invariant power spectrum from adiabatic vacuum fluctuations relies on first order derivative of fields in the action for cur…