Theory Seminar (High Energy/Cosmology) |
Events During the Week of October 26th through November 2nd, 2025
Monday, October 27th, 2025
- Taming Axion Rotation: Dark Vector-like Confinement for Axiogenesis
- Time: 1:00 pm - 2:30 pm
- Place: Chamberlin 5280
- Speaker: Pouya Asadi, UC, Santa Cruz
- Abstract: I show that extending the Standard Model with two axions and a dark vector-like confining gauge group can simultaneously account for both the observed dark matter abundance and the baryon asymmetry of the Universe - a step toward resolving the matter coincidence problem. Starting from a review of sphaleron dynamics, I derive both (i) the axion-induced contributions to fermion asymmetries and (ii) the back-reaction of these fermion asymmetries on axion-like fields, which manifests as a friction on the axions. This analysis clarifies why the minimal axiogenesis scenario cannot produce the correct dark matter and baryon abundances simultaneously. We then show that introducing a second axion and an additional vector-like dark confining sector - a natural infrared realization in the well-motivated axiverse frameworks - resolves this tension by providing a distinct source of friction in the axion dynamics. Finally, we discuss possible UV completions of this setup in extra-dimensional models of high-quality axions. Beyond its cosmological implications, this framework motivates searches for the QCD axion and predicts complementary Light-Shining-through-Wall signatures probing the second axion in the ~eV mass range. Event recording:
- Host: Lisa L Everett
Tuesday, October 28th, 2025
- No events scheduled
Wednesday, October 29th, 2025
- No events scheduled
Thursday, October 30th, 2025
- No events scheduled
Friday, October 31st, 2025
- No events scheduled