283 citations · 1.4k across the 45 of their papers we have counts for
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Expected dipole asymmetry in CMB polarization
M. H. Namjoo, A. A. Abolhasani, H. Assadullahi +3
We explore the hemispherical asymmetry predicted in cosmic microwave background polarization when there is an asymmetry in temperature anisotropies due to primordial perturbations.…
Models of the Primordial Standard Clock
Xingang Chen, Mohammad Hossein Namjoo, Yi Wang
Oscillating massive fields in the primordial universe can be used as Standard Clocks. The ticks of these oscillations induce features in the density perturbations, which directly r…
CMB hemispherical asymmetry from non-linear isocurvature perturbations
Hooshyar Assadullahi, Hassan Firouzjahi, Mohammad Hossein Namjoo +1
We investigate whether non-adiabatic perturbations from inflation could produce an asymmetric distribution of temperature anisotropies on large angular scales in the cosmic microwa…
Fingerprints of Anomalous Primordial Universe on the Abundance of Large Scale Structures
Shant Baghram, Ali Akbar Abolhasani, Hassan Firouzjahi +1
We study the predictions of anomalous inflationary models on the abundance of structures in large scale structure observations. The anomalous features encoded in primordial curvatu…
CMB Hemispherical Asymmetry: Long Mode Modulation and non-Gaussianity
Mohammad Hossein Namjoo, Ali Akbar Abolhasani, Shant Baghram +1
The observed hemispherical asymmetry in CMB map can be explained by modulation from a long wavelength super horizon mode which non-linearly couples to the CMB modes. We address the…
Scale-dependent hemispherical asymmetry from general initial state during inflation
Hassan Firouzjahi, Jinn-Ouk Gong, Mohammad Hossein Namjoo
We consider a general initial state for inflation as the mechanism for generating scale-dependent hemispherical asymmetry. An observable scale-dependent non-Gaussianity is generate…
Jump in fluid properties of inflationary universe to reconcile scalar and tensor spectra
Hassan Firouzjahi, Mohammad Hossein Namjoo
The recent detection of the primordial gravitational waves from the BICEP2 observation seems to be in tension with the upper bound on the amplitude of tensor perturbations from the…
Standard Clock in Primordial Density Perturbations and Cosmic Microwave Background
Xingang Chen, Mohammad Hossein Namjoo
Standard Clocks in the primordial epoch leave a special type of features in the primordial perturbations, which can be used to directly measure the scale factor of the primordial u…