{ "id": "math/0703503", "version": "v2", "published": "2007-03-16T21:58:20.000Z", "updated": "2008-01-31T22:28:22.000Z", "title": "The Littlewood-Offord Problem and invertibility of random matrices", "authors": [ "Mark Rudelson", "Roman Vershynin" ], "comment": "Introduction restructured, some typos and minor errors corrected", "categories": [ "math.PR", "math.FA" ], "abstract": "We prove two basic conjectures on the distribution of the smallest singular value of random n times n matrices with independent entries. Under minimal moment assumptions, we show that the smallest singular value is of order n^{-1/2}, which is optimal for Gaussian matrices. Moreover, we give a optimal estimate on the tail probability. This comes as a consequence of a new and essentially sharp estimate in the Littlewood-Offord problem: for i.i.d. random variables X_k and real numbers a_k, determine the probability P that the sum of a_k X_k lies near some number v. For arbitrary coefficients a_k of the same order of magnitude, we show that they essentially lie in an arithmetic progression of length 1/p.", "revisions": [ { "version": "v2", "updated": "2008-01-31T22:28:22.000Z" } ], "analyses": { "subjects": [ "15A52", "11P70" ], "keywords": [ "littlewood-offord problem", "random matrices", "smallest singular value", "invertibility", "minimal moment assumptions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007math......3503R" } } }