There will be a CIRCA seminar on Thursday 21st September at 1pm in Theatre D of Maths.

Ian Miguel will speak on Puzznic and Colva Roney-Dougal will count the subgroups of the symmetric group.

Arne Van Antwerpen will be here on 16/17/18 May, visiting Olexandr Konovalov.

Arne will give a CIRCA seminar on the Wednesday afternoon, 4-5 in Theatre C.

Title: Multipermutation solutions of the Yang-Baxter equation and nilpotency of skew braces

Abstract: This talk will be based on joint work with Eric Jespers and Leandro Vendramin. The class of multipermutation solutions is a particularly interesting class of solutions of the celebrated Yang-Baxter equation (coming from mathematical physics) with a beautiful combinatorial structure. It was shown that this class corresponds to right nilpotent skew left braces of nilpotent type. In this talk we delve deeper into this class of skew left braces and identify the class of centrally nilpotent skew braces. We discuss that these behave very similar to nilpotent groups and will identify several possible central series for these objects. If time permits, we use this class to illustrate several other key concepts of skew left braces. The talk will be rife with examples and exciting open problems.

All welcome!

Pascal Schweitzer from TU-Darmstadt will visit CIRCA on Wednesday May 10th, and give a talk at 4pm in Maths C. All welcome.

The final CIRCA seminar of the semester will be on 13th April, at 1pm in Theatre C of Maths.

Ian Gent will speak on A Dream Model for Black Hole

Murray Whyte will speak on Irredundant monoid presentations

All welcome

The final two CIRCA seminars of term will be

Thursday 17th November: Finn Smith and Jacob Beaddie

Thursday 24th November: Michael Young and Peter Cameron. Note the unusual date for this one, and also that it will be in Purdie C rather than Maths.

The seminars for Autumn 2022 will be held on Thursdays of even weeks at 1pm in Theatre B of Maths. The schedule at present is:

September 22nd: Colva Roney-Dougal and Chris Jefferson

October 6th: Ruth Hoffman and Alan Logan

October 20th: Saul Freedman and Ozgur Akgun

November 3rd: Jendrik Brachter (TU Darmstadt)

November 17th: TBA

December 1st: Michael Young and Peter Cameron

From 29th July-2nd August Rosemary Bailey, Peter Cameron, and Siavash Lashkarighouchani attended the British Combinatorial Conference at the University of Birmingham. Peter organised a mini-symposium on Designs and Latin Squares, at which Rosemary spoke on ‘Substitutes for the non-existent square lattice design for 36 treatments’. Peter also contributed a talk on ‘Hall-Paige and synchronization’. At the conference business meeting, Peter was re-elected chair of the British Combinatorial Committee, a position he has held for 25 years.

Peter Cameron spent the week 22nd-26th July at the London Mathematical Society’s Undergraduate Summer School at the University of Leeds, where he gave two talks, one on ‘Problems around graphs, groups and semigroups’ and one on ‘The random graph’.

CIRCA members took part in the Research Day, held in the School of Mathematics and Statistics on 24th January 2019. The speakers were Rosemary Bailey, Collin Bleak, Peter Cameron, Martyn Quick, Louis Theran, and Peter Cameron. Olexandr Konovalov and Michael Torpey presented a poster.

The schedule of Algebra and Combinatorics Seminars for February-May 2018 can be found here. They will run on Wednesdays at 1pm in Lecture Theatre D.