High Energy Theory Seminar: Making massive spin-2 particles from gravity during and after inflation

Andrew Long (Rice University)
- | David Rittenhouse Laboratory, 3W2
An image of Andrew Long

The phenomenon of cosmological gravitational particle production (CGPP) occurs during and after inflation as quantum fields “feel” the cosmological expansion are excited out of their ground state.  CGPP is a compelling and minimal explanation for the origin of dark matter, which might only interact gravitationally, as well as other cosmological relics.  In this talk, I’ll provide a general introduction to CGPP and then focus on our recent study of CGPP for massive spin-2 particles.  I’ll briefly discuss the embedding of massive spin-2 particles into the framework of bigravity, present our results for the spectrum of gravitationally produced particles, and discuss a related by-product of our analysis: an FRW-generalization of the Higuchi bound (ghost-avoidance of massive gravity on dS backgrounds).