Expander Graphs and Finite Simple Groups
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Pcmi Lecture Notes on Property (t ), Expander Graphs and Approximate Groups (preliminary Version)
The final aim of these lectures will be to prove spectral gaps for finite groups and to turn certain Cayley graphs into expander graphs. However in order to do so it is useful to have some understanding of the analogous spectral notions of amenability and Kazhdan property (T ) which are important for infinite groups. In fact one important aspect of asymptotic group theory (the part of group the...
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