Pure PGR Seminar - Howson's Property and the Hanna Neumann Conjecture, Naomi Andrew (Southampton) Seminar
- Time:
- 15:00 - 16:00
- Date:
- 14 February 2018
- Venue:
- Lecture Theatre 5A, Room 5027, Building 54, Mathematical Sciences, University of Southampton, Highfield Campus, SO17 1BJ
For more information regarding this seminar, please email Motiejus Valiunas at M.Valiunas@southampton.ac.uk .
Event details
Howson's theorem on the rank of the intersection of (finitely generated) subgroups of free groups led to more results along similar lines: better bounds for free groups, and proofs or counterexamples of the same property for other groups. Hanna Neumann's conjectured bound for this rank was an open problem from when she first posed it in 1957 until two (very different) proofs were completed in 2011. I'll talk about (some) of the history of these results, including a proof of the strengthened form of Neumann's conjecture.
Speaker information
Naomi Andrew , PGR at the University of Southampton.