Abstract: Evidence shows that we live in a universe where 95% of the matter and energy is of unknown nature. Right from the onset, Gravitational Wave (GW) astronomy is shaping our understanding of the dark universe in several ways: GW signals of black hole mergers have resurrected the idea of Dark Matter being made of primordial black holes, while multi-messenger … Read More
Long ago Weinberg showed, from first principles, that the amplitude for a single photon exchange between an electric current and a magnetic current violates Lorentz invariance. The obvious conclusion at the time was that monopoles were not allowed in quantum field theory. Since the discovery of topological monopoles there has thus been a paradox. On the one hand, topological monopoles … Read More
Many experimental efforts have been devoted to searching for dark photon dark matter. However, the currently known production mechanisms face various difficulties, including a limited dark photon mass range. It is therefore of interest to explore alternative sources of dark photons with broader mass ranges. We propose a new production mechanism via tachyonic instability- the exponential growth of dark photons … Read More
In this talk, I will explore two recent developments in the search for dark matter. First, I will discuss how the 21-cm global signal measurement constrains the potential impact of dark matter annihilation/decay on the thermal history of the universe. I will also explain how to accurately compute such modifications to the baryon temperature in the early universe using a … Read More
Abstract: The appealing feature of inverse seesaw models is that the neutrino mass emerges from the exchange of TeV scale singlets with sizable Yukawa couplings, which can be tested at colliders. However, the tiny Majorana mass splitting between TeV singlets is left unexplained. Moreover, we argue that these models suffer from a structural limitation that prevents a successful thermal leptogenesis … Read More
I will discuss the implications of LHCb results that show intriguing hints for lepton flavor universality violation in rare B meson decays. These hints are fully consistent with several other anomalies that have been observed in rare B decays over the last few years. A very good description of all the data is obtained by new physics in form of … Read More
Dark Matter (DM) provides strong evidence for physics beyond the Standard Model (SM). Arguably, rather than suggesting a specific mass scale for New Physics, it may point to a dark sector, weakly-coupled to the SM, as hinted at by the comparable abundances of dark matter and visible baryons. In the past few years, a program of new experiments has expanded … Read More