Dark Matter, Inflation, and Gravitational Production of Particles with Spin

Cosmic inflation provides not only a "cosmological collider" to generate signals of new particle species, but also a 'particle factory' to generate non-thermal relics, including dark matter. In this talk I will discuss the primordial production of particles with spin, focusing on spin-1, spin-3/2, and bosonic higher-spin fields, as well as the Kalb-Ramond antisymmetric tensor field, via gravitational particle production. Far from being a repetitive exercise, each case offers something new, such as enhanced production and/or unforeseen instabilities, which constrain the theoretically allowed dark matter parameter space and the underlying field theory.