Speaker
Anish Ghoshal
(University of Warsaw, Poland)
Description
Cosmological collider signals of primordial non-Gaussianity arise at tree level when a particle has Hubble mass during inflation. We critically review the formalism finding that a large class of inflationary theories, based on Planck-scale physics, predict a scalar bi-spectrum around the gravitational floor level. This mild signal arises for example in R2 gravity, in the regime where its gravitational scalar has Hubble-scale mass. Signals much above the gravitational floor arise in theories where scalars undergo multiple turns during inflation, thanks to sub-Planckian physics.
Author
Anish Ghoshal
(University of Warsaw, Poland)