| Friday 9 May 2025 | |
| Events for day: Wednesday 26 February 2025 |
| 14:00 - 15:00 Combinatorics and Computing Weekly Seminar Extremal Minimal Bipartite Matching covered Graphs School MATHEMATICS A connected graph, on four or more vertices, is matching covered if every edge is present in some perfect matching. An ear decomposition theorem (similar to the one for 2-connected graphs) exists for bipartite matching covered graphs due to Hetyei (1964). From the results and proofs of Lovasz and Plummer, that rely on Hetyei's theorem, one may deduce that any minimal bipartite matching covered graph has at least 2(m − n + 2) vertices of degree two (where minimal means that deleting any edge results in a graph that is not matching covered); such a graph is said to be extremal if it attains the stated lower bound. We provide ... 16:00 - 17:00 Mathematics Colloquium The Idea of Hypergeometry School MATHEMATICS The concept of hypergeometric functions was coined by John Wallis in the middle of 17th century as a generalization of many elementary functions. Since then, these functions have played a key role in various branches of mathematics. Great mathematicians such as Euler, Gauss, Riemann and Klein have investigated the theory of hypergeometric functions from various aspects and have shown the role of these functions in the connection of differential equations, geometry and number theory. In the 20th century, with the generalizations of these functions, unexpected applications of them in theoretical physics (string theory) were found, which led to ... |