195 citations · 1.1k across the 29 of their papers we have counts for
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Signatures of kinetic and magnetic helicity in the CMBR
Levon Pogosian, Tanmay Vachaspati, Serge Winitzki
P and CP violation in cosmology can be manifested as large-scale helical velocity flows in the ambient plasma and as primordial helical magnetic fields. We show that kinetic helici…
Cosmic String Signatures in the Cosmic Microwave Background Anisotropies
Alejandro Gangui, Levon Pogosian, Serge Winitzki
We briefly review certain aspects of cosmic microwave background anisotropies as generated in passive and active models of structure formation. We then focus on cosmic strings base…
Null Energy Condition Violations in Eternal Inflation
Serge Winitzki
The usual scenario of ``eternal inflation'' involves an approximately de Sitter spacetime undergoing upward fluctuations of the local expansion rate . This spacetime requires fr…
The eternal fractal in the universe
Serge Winitzki
Models of eternal inflation predict a stochastic self-similar geometry of the universe at very large scales and allow existence of points that never thermalize. I explore the fract…
CMB Bispectrum from Active Models of Structure Formation
Alejandro Gangui, Levon Pogosian, Serge Winitzki
We propose a new method for a numerical computation of the angular bispectrum of the CMB anisotropies arising from active models such as cosmic topological defects, using a modifie…