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                * Princeton Discrete Math Seminar *
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Speaker: Rose McCarty

Thursday 21st April, 3:00 in Fine Hall 224.

Title: A min-max theorem for circuit decompositions of group-labelled
graphs

Abstract: This talk focuses on Eulerian graphs whose arcs are directed and
labelled in a group. Each circuit yields a word over the group, and we say
that a circuit is "non-zero" if this word does not evaluate to 0.
We give a precise min-max theorem for the following problem. Given a
vertex v, what is the maximum number of non-zero circuits in a circuit
decomposition where each circuit begins and ends at v?

This is joint work with Jim Geelen and Paul Wollan. Our main motivation is
a surprising connection with vertex-minors which is due to Bouchet and
Kotzig.

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