Speaker
Description
Massive field excitations during the inflationary era, imprinted on cosmological correlation functions, have been studied as a unique opportunity to probe heavy degrees of freedom beyond the terrestrial colliders. In the simplest inflationary models, any such cosmological collider signal is exponentially suppressed for fields much heavier than the inflationary Hubble scale, limiting the potential reach of such new physics searches. We show that existence of high-frequency classical oscillations can resonantly enhance heavy field signals. In particular, we study two concrete examples of such classical oscillations: (i) coherent oscillation of another massive field, classically excited due to a sharp feature in a generic multi-field scenario, and (ii) sub-dominant oscillations of the inflaton itself, as a result of periodic features on the inflationary potential.
