Contatto di riferimento: Barbara Simoni
Partecipanti: Dr. Luca Visinelli: Stockholm University
Abstract: The low-energy limit of several string theories feature what is known as the “axiverse”, a plethora of light axions with masses spanning various orders of magnitude. I will first discuss astrophysical and cosmological constraints on axions at either end of this spectrum, using data from the cosmic microwave background anisotropies and from the gravitational microlensing. I then show how to assess the string parameters using a series of Bayesian analyses that take into account current limits on the tensor-to-scalar ratio and the primordial isocurvature fraction. Based on hep-ph/1809.06382.