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                * Princeton Discrete Math Seminar *
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Date: Thursday 26th September, 4:30 in Fine Hall 224.
 
Speaker: Eli Berger, Haifa

The algebraic and topological properties of claw-free graphs.

We study two parameters that can be associated with a graph. The first 
parameter is algebraic: the maximal eigenvalue of the Laplacian. The second 
parameter is topological: the connectivity of the simplicial complex of 
independent sets. These two parameters are useful in studying combinatorial 
properties of the graph, such as the existence of independent transversals. 
In previous work with Aharoni and Meshulam, we showed that these two 
parameters are related. In this talk we show that for claw-free graphs we
can obtained bounds for these parameters that are better than the ones known 
for general graphs. Similar results are obtained for K_{1,k}-free graphs 
for any k.

This is joint work with Noga Alon and Ron Aharoni.


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Next week: No seminar (Banff meeting)

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