Discrete Groups, Expanding Graphs and Invariant Measures: 125 (Progress in Mathematics, 125) - Hardcover

Lubotzky, Alex

Hardcover

ISBN 10: 376435075X ISBN 13: 9783764350758

Publisher: Birkhauser Verlag AG, 1994

Synopsis

This text presents the solution to two problems - the construction of expanding graphs (which are of fundamental importance for communication networks and computer science) and the Ruziewicz problem concerning the finitely added invariant measures on spheres. Both problems were partially solved using the Kazhdan property (T) from representation theory of semi-simple Lie groups. Later, complete solutions were obtained for both problems using the Ramanjuan conjecture from analytic number theory. The author, who played an important role in these developments, explains the two problems and their solutions from a perspective which reveals why all these seemingly unrelated topics are so interconnected. The unified approach shows interrelations between different branches of mathematics such as graph theory, measure theory, Riemannian geometry, discrete subgroups of Lie groups, representation theory and analytic number theory. The book has been made accessible to graduate students in mathematics and computer science. A number of problems and suggestions for further research are included.

About this title

Review

From reviews:

"This exciting book marks the genesis of a new field. It is a field in which one passes back and forth at will through the looking glass dividing the discrete from the continuous. (...) The book is a charming combination of topics from group theory (finite and infinite), combinatorics, number theory, harmonic analysis." - Zentralblatt MATH

"The Appendix, written by J. Rogawski, explains the Jacquet-Langlands theory and indicates Deligne’s proof of the Petersson-Ramanujan conjecture. It would merit its own review. (...) In conclusion, this is a wonderful way of transmitting recent mathematical research directly "from the producer to the consumer". - MathSciNet

"The book is accessible to mature graduate students in mathematics and theoretical computer science. It is a nice presentation of a gem at the border of analysis, geometry, algebra and combinatorics. Those who take the effort to glance what happens behind the scene won’t regret it." - Acta Scientiarum Mathematicarum

Edition details

• Publisher: Birkhauser Verlag AG
• Publication date: 1994
• Language: English
• ISBN 10: 376435075X
• ISBN 13: 9783764350758
• Binding: Hardcover
• Number of pages: 207