4 papers · 1 filter
Signatures of Primordial Energy Injection from Axion Strings
Joshua N. Benabou, Malte Buschmann, Soubhik Kumar +2
Axion strings are horizon-size topological defects that may be produced in the early Universe. Ultra-light axion-like particles may form strings that persist to temperatures below…
Unraveling Cosmological Anisotropies within Stochastic Gravitational Wave Backgrounds
Yanou Cui, Soubhik Kumar, Raman Sundrum +1
Identifying the anisotropies in a cosmologically sourced stochastic gravitational wave background (SGWB) would be of significance in shedding light on the nature of primordial inho…
Gravitational Waves from Stochastic Scalar Fluctuations
Reza Ebadi, Soubhik Kumar, Amara McCune +2
We present a novel mechanism for gravitational wave generation in the early Universe. Light spectator scalar fields during inflation can acquire a blue-tilted power spectrum due to…
Dissipative Inflation via Scalar Production
Paolo Creminelli, Soubhik Kumar, Borna Salehian +1
We describe a new mechanism that gives rise to dissipation during cosmic inflation. In the simplest implementation, the mechanism requires the presence of a massive scalar field wi…