We revisit a class of lepton-flavor non-universal $\mathrm{U}(1)$ gauge extensions of the Standard Model, first introduced in~\cite{Davighi:2022qgb}, which provides a subtle mechanism to simultaneously accommodate the observed neutrino masses and mixing angles via a high-scale seesaw while predicting exact proton stability to all orders in the effective field theory, ensured by a residual...
In this talk, I will discuss the generation of a lepton asymmetry during
a first-order cosmological phase transition at which the sterile neutrinos of the seesaw
mechanism acquire their masses. Contrary to previous works who studied the same
problem, we compute the lepton asymmetry by solving quantum kinetic equations
derived from nonequilibrium quantum field theory, which take into...
I will discuss recent progress in the determination of parameters of thermal-phase transitions, relevant for describing production of gravitational wave backgrounds in the early Universe, using effective field theory (EFT) methods. I will highlight the importance of including previously neglected terms in the EFT expansion and the difficulties and solutions for computing the corresponding...
Vacuum decay through runaway first order phase transitions presents a unique opportunity for particle physics and cosmology: collisions of vacuum bubbles can act as cosmic scale high energy colliders close to the Planck scale, providing access to high energy physics far beyond any temperature or energy scale ever reached in the history of our Universe. This talk will cover recent developments...
The recent laser excitation of the low-lying Th-229 isomer transition is starting a revolution in ultralight dark matter searches. The enhanced sensitivity of this transition to the large class of dark matter models dominantly coupling to quarks and gluons will ultimately allow us to probe coupling strengths eight orders of magnitude smaller than the current bounds from optical atomic clocks,...
