| Thursday 21 November 2024 | |
| Events for day: Wednesday 06 November 2024 |
| 11:00 - 12:00 Wednesday Weekly Seminar - Hybrid Format The charge and magnetic radii of the nucleons from the generalized parton distributions School PARTICLES AND ACCELERATORS Abstract: The proton-radius puzzle refers to the discrepancy observed in measurements of the proton's charge radius when using different methods. This inconsistency has prompted extensive research and debate within the physics community, as it challenges the understanding of quantum electrodynamics and the fundamental properties of protons. In the present study, we determine the charge and magnetic radii of the proton and neutron through a global analysis of the generalized parton distributions (GPDs) at zero skewness for the first time. Our results challenge the measurements or analyses in which the nucleon's radii are extract ... 14:00 - 15:00 Combinatorics and Computing Weekly Seminar Chi-boundedness and Exclusion of Complete Graphs School MATHEMATICS The connection between excluding complete graphs (for various notions of exclusion) and the chromatic number of graphs is nearly a century old. In the 1940s, Hadwiger conjectured that a graph with no $K_n$-minor is $(n-1)$-colorable. Later, in the 1950s, Hajos proposed a strengthening of this conjecture, that every graph containing no subdivision of $K_n$ as a subgraph, is $(n-1)$-colorable. While both conjectures remain unresolved in some cases, a bound $c=c(n)$ (instead of $n-1$) for the chromatic number is known for every $n$ for both conjectures. A natural attempt to strengthen this result would be to ask whether there exists a ... |