TEL AVIV UNIVERSITY
 
Hello everyone,
 
The next colloquium talk will be held on:
 
Monday, 12/11/2012, 12:15, Schreiber 006, Tel Aviv University.
 
Speaker: Amos Nevo (Technion)
 
Title: Diophantine approximation, arithmetic groups, and ergodic theory.
 
The abstract is given below. Tea and coffee at 12:00, same room.
 
Hope to see you there. For information about future colloquia, see
 <http://www.math.tau.ac.il/~ostrover/colloquium/colloq2012.html>
 
Yours,
Yaron
 
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Abstract: One of the main goals of classical metric Diophantine
approximation is to quantify the denseness of the rational numbers
in the real numbers, or more generally, of Q^d in R^d. An equally
natural problem is to quantify the denseness of the rational points
on the sphere, and more generally, rational points in other compact
and non-compact algebraic sub-varieties in R^d. We will describe a
solution to this problem for a large class of homogeneous varieties.
The method we use is based on a general quantitative duality principle in
homogeneous dynamics that we develop, and on spectral estimates of ergodic
averages using the theory of automorphic forms.
 
Based on joint work with Alex Gorodnik, and on joint work with
Anish Ghosh and Alex Gorodnik.
 
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Technion Math Net-2 (TECHMATH2)
Editor: Michael Cwikel   <techm@math.technion.ac.il> 
Announcement from:  <ostrover@post.tau.ac.il>