PIMS-Math Analysis Seminar: Pierre Youssef
Topic
Extracting a large well-coniditoned block inside a matrix
Speakers
Details
Given U an n×m matrix, the aim is to extract a large number of linearly independent columns of U and estimate the smallest and the largest singular value of the restricted matrix. For that, we give two deterministic algorithms: one for a normalized version of the restricted invertibility principle of Bourgain-Tzafriri, and one for the norm of coordinate restriction problem due to Kashin-Tzafriri. Merging the two algorithms, we are able to extract a well-conditioned block inside U, improving a previous result due to Vershynin. We give some applications of this result to the study of contact points of a convex body.
Additional Information
Location: Math Annex 1118
Pierre Youssef, U. Alberta
Pierre Youssef, U. Alberta
This is a Past Event
Event Type
Scientific, Seminar
Date
November 28, 2013
Time
-
Location