Dr. Davide Racco

Research area

I am interested in topics at the crossover between Particle Physics and Cosmology, focusing in particular on dark matter, gravitational waves, non-Gaussianities, Higgs metastability and early universe.

My main area of interest is Dark Matter, and I have worked on various classes of candidates, ranging from WIMPs (particles with masses and interaction strengths comparable to the Standard Model particles, who are currently the target of many experimental searches) to Primordial Black Holes (hypothetical black holes that could have formed in the early history of the Universe) and axions (particles which would also solve the strong CP problem in particle physics). Concerning the production mechanism for Dark Matter, recently I have been studying gravitational production during inflation, which is a well-motivated and minimal scenario and can guide the identification of benchmarks for direct detection.

I am also very interested in stochastic backgrounds of primordial Gravitational Waves (GW). Their potential discovery would disclose precious information on the cosmology of the early universe, and the particle content at high energy scales. In particular, I have contributed to the study of GW backgrounds generated by large scalar perturbations, and I have highlighted the remarkable properties of the low-frequency spectrum (causality tail) of a wide class of primordial sources of GW backgrounds.

Finally, I have also explored various axpects of the physics of the inflationary universe, and its discovery potential in relation to the instability of the Higgs in the Standard Model, both as a minimal signature at the cosmological collider and as a possible source of primordial black holes and a GW background.