| Saturday 11 January 2025 | |
| Events for day: Wednesday 22 September 2021 |
| 11:00 - 12:00 Wednesday Weekly Seminar - google meet Filtered asymmetric dark matter during the Peccei-Quinn phase transition School PARTICLES AND ACCELERATORS Abstract: In this talk, I present a bubble filtering-out mechanism for an asymmetric dark matter scenario during the Peccei-Quinn (PQ) phase transition. Based on a QCD axion model, extended by extra chiral neutrinos, I show that the PQ phase transition can be first order in the parameter space of the model and regarding the PQ symmetry breaking scale, the mechanism can generate PeV-scale heavy neutrinos as a dark matter candidate. Considering a CP-violating source, during the phase transition, discriminating between the neutrino and antineutrino number density, the observed dark matter relic abundance is found. I then obtain effective couplin ... 13:30 - 15:00 Weekly Seminar (Online) Gravity and cosmology beyond general relativity and gravitational waves https://www.skyroom.online/ch/soa/weekly-seminar School ASTRONOMY After motivating gravity and cosmology beyond general relativity, I will discuss some theories and their phenomenology, including gravitational waves ... 14:00 - 15:00 Weekly Seminar Taming Active Matter: from ordered topological defects to autonomous shells School NANO SCIENCES The spontaneous emergence of collective flows is a generic property of active fluids and often leads to chaotic flow patterns characterized by swirls, jets, and topological disclinations in their orientation field. I will first discuss two examples of these collective features helping us understand biological processes: (i) to explain the tortoise & hare story in bacterial competition: how motility of Pseudomonas aeruginosa bacteria leads to a slower invasion of bacteria colonies, which are individually faster, and (ii) how self-propelled defects lead to finding an unanticipated mechanism for cell death. < ... 16:30 - 17:30 Fun with Curves School ISFAHAN BRANCH OF MATHEMATICS Lecture |