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On the Banach-Space-Valued Azuma Inequality and Small-Set Isoperimetry of Alon–Roichman Graphs

Published online by Cambridge University Press:  18 January 2012

ASSAF NAOR*
Affiliation:
Courant Institute, 251 Mercer Street, New York, NY 10012, USA (e-mail: naor@cims.nyu.edu)

Abstract

We discuss the connection between the expansion of small sets in graphs, and the Schatten norms of their adjacency matrices. In conjunction with a variant of the Azuma inequality for uniformly smooth normed spaces, we deduce improved bounds on the small-set isoperimetry of Abelian Alon–Roichman random Cayley graphs.

Type
Paper
Copyright
Copyright © Cambridge University Press 2012

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