***********************************
                * Princeton Discrete Math Seminar *
                ***********************************

Speaker: Alex Scott (U Oxford)

Thursday 3rd September, 3:00 in Fine Hall 224.

Title: Colour-balanced matchings

A k-edge-coloured graph is balanced if each colour appears equally often. Given
a balanced k-edge-colouring of a complete graph with an even number of vertices,
is there a perfect matching on which the colouring is close to balanced? 
Proving a strengthened version of a conjecture of Pardey and Rautenbach, we show
that there is a perfect matching that is within O(k^2) edges of balanced. More
generally, we prove results for arbitrary bounded-degree spanning subgraphs,
answering a question of Banerjee and Hollom, and extend our results to
hypergraphs.  This significantly improves earlier bounds for all previously
studied classes of subgraph. Joint work with Emma Hogan and Dmitry Tsarev.

		----------------------------------

Anyone wishing to be added to or removed from the mailing list should
contact Paul Seymour (pds@math.princeton.edu)