| Friday 26 April 2024 | |
| Events for day: Wednesday 11 May 2022 |
| 14:00 - 15:00 Combinatorics and Computing Weekly Seminar Size Ramsey Number of Galaxies School MATHEMATICS Given graphs G, H and F, we say that F is Ramsey for (G, H) and we write F → (G, H), if for every edge coloring of F by red and blue, there is either a red copy of G or a blue copy of H in F. The size Ramsey number r?(G, H) is defined as the minimum number of edges of a graph F such that F → (G, H). In 1978, Burr, Erdős, Faudree, Rousseau and Schelp conjectured the exact value of r?(G, H), whenever G and H are two arbitrary galaxies. In this talk, we give a partial solution to the conjecture by proving it for many pairs (G, H) of star forests. To get more information about the Combinatorics and Computing ... 15:30 - 16:30 Mathematical Logic Weekly Seminar Forcing a Club by a Generalized Fast Function School MATHEMATICS Three new proper posets are introduced. Each is made up of finite conditions and allows amalgamations. The first one forces a partial function whose domain is a closed and cofinal subset of the least uncountable cardinal. The other two incorporate the first and force either a continuous epsilon chain, or a symmetric family, of countable elementary substructures of a transitive model of a set theory, The symmetric family projects down to a gap one morass of Velleman. Zoom info: https://us06web.zoom.us/j/86380285511?pwd=Z2puU2w0NzIwL3doM1ljcCtBdHFFdz09 Meeting ID: 863 8028 5511 Passcode: 362880 ... |