Institute for Advanced Study Astrophysics Seminar

ABSTRACT: The CMB spectrum is known to be extremely close to a perfect blackbody. However, even within standard cosmology several processes occurring in the early Universe lead to distortions of the CMB at a level that might become observable in the future. In my talk I will briefly review the cosmological thermalization problem, which is crucial for understanding how primordial spectral distortions could be created and how they evolve. I will then explain in more detail how the cooling of matter in the early Universe causes a negative mu- and y-type distortion and how the damping of primordial small-scale perturbations before recombination allows placing interesting constraints on different inflationary models.