283 citations · 1.4k across the 45 of their papers we have counts for
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Probing the Primordial Universe using Massive Fields
Xingang Chen, Mohammad Hossein Namjoo, Yi Wang
Inflation models are numerous. It is extremely difficult, if possible at all, to identify the actual underlying inflation model of our primordial universe. Thus, for the purpose of…
Fluid Inflation
Xingang Chen, Hassan Firouzjahi, Mohammad Hossein Namjoo +1
In this work we present an inflationary mechanism based on fluid dynamics. Starting with the action for a single barotropic perfect fluid, we outline the procedure to calculate the…
Cosmological Perturbations in Inflationary Models with Anisotropic Space-Time Scaling in Lifshitz Background
Mohsen Alishahiha, Hassan Firouzjahi, Kazuya Koyama +1
Models of inflation in a gravitational background with an anisotropic space-time scaling are studied. The background is a higher-dimensional Lifshitz throat with the anisotropy sca…
Modulated curvaton decay
Hooshyar Assadullahi, Hassan Firouzjahi, Mohammad Hossein Namjoo +1
We study primordial density perturbations generated by the late decay of a curvaton field whose decay rate may be modulated by the local value of another isocurvature field, analog…
Multiple Inflationary Stages with Varying Equation of State
Mohammad Hossein Namjoo, Hassan Firouzjahi, Misao Sasaki
We consider a model of inflation consisting a single fluid with a time-dependent equation of state. In this phenomenological picture, two periods of inflation are separated by an i…
DBI Lifshitz Inflation
Mohsen Alishahiha, Hassan Firouzjahi, Mohammad Hossein Namjoo
A new model of DBI inflation is introduced where the mobile brane, the inflaton field, is moving relativistically inside a Lifshitz throat with an arbitrary anisotropic scaling exp…