Beschreibung
Recent developments in the cosmological collider programme have highlighted the possibility of probing new particle species present during inflation. In these scenarios, the inflaton couples to additional massive fields whose exchange leaves distinctive imprints in primordial correlation functions. In particular, the bispectrum exhibits characteristic momentum dependence controlled by the particle mass and angular dependence determined by its spin. These signatures open the possibility of using the primordial Universe as a particle collider capable of probing energies inaccessible to laboratory experiments.
In this talk, I will review recent developments in cosmological collider physics and describe how primordial bispectrum templates can be derived in a model-independent way using the boostless bootstrap. Next, I will summarize current observational efforts to detect cosmological collider signals, mostly in the cosmic microwave background (CMB). I will present current constraints on a range of cosmological collider scenarios and discuss the treatment of the look-elsewhere effect and future prospects for detecting cosmological collider signals.