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On the spectrum of projective norm-graphs

✍ Scribed by Tibor Szabó

Publisher
Elsevier Science
Year
2003
Tongue
English
Weight
67 KB
Volume
86
Category
Article
ISSN
0020-0190

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✦ Synopsis

We show that the projective norm-graphs of Alon et al. [J. Combin. Theory Ser. B 76 (1999) 280-290] are pseudorandom in the sense that their second eigenvalue is as small as the square root of the degree. Our approach is simple, it only uses the evaluation of Gaussian sums and determines the complete spectrum exactly.

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