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                * Princeton Discrete Math Seminar *
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Date: Thursday 7th November, 4:30 in Fine Hall 224.
 
Speaker: Krystal Guo (Simon Fraser U.)

Title: Simple eigenvalues of vertex-transitive graphs

A simple eigenvalue of a graph is an eigenvalue of the adjacency
matrix with multiplicity 1. It has been observed that graphs having
many simple eigenvalues tend to have small automorphism groups. The
only vertex-transitive graph with all eigenvalues simple is K_2 and
it is well-known that a k-regular vertex-transitive graph will have
at most k+1 simple eigenvalues. We will look at structural
properties of vertex-transitive graphs with many simple eigenvalues.

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Next week: Dillon Mayhew

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