# Replacement and zig-zag products, Cayley graphs and Lamplighter random walk

Document Type: Ischia Group Theory 2012

Author

Università di Roma "La Sapienza"

Abstract

‎We investigate two constructions‎ - ‎the replacement and the zig-zag‎ ‎product of graphs‎ - ‎describing several fascinating connections‎ ‎with Combinatorics‎, ‎via the notion of expander graph‎, ‎Group‎ ‎Theory‎, ‎via the notion of semidirect product and Cayley graph‎, ‎and‎ ‎with Markov chains‎, ‎via the Lamplighter random walk‎. ‎Many examples‎ ‎are provided‎.

Keywords

Main Subjects

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