Timeline for The rank of a perturbed triangular matrix

11 events

when toggle format	what		by	license	comment
Nov 17, 2017 at 3:59	vote	accept	Seva
Nov 16, 2017 at 19:28	answer	added	Boris Bukh		timeline score: 3
Jun 27, 2017 at 10:01	answer	added	Seva		timeline score: 3
S May 30, 2017 at 9:58	history	rollback	Seva		Rollback to Revision 1 - Edit approval overridden by post owner or moderator
May 30, 2017 at 8:12	history	suggested	user35593		added two tags because its equivalent graph theoretic formulation
May 30, 2017 at 7:38	review	Suggested edits
S May 30, 2017 at 9:58
May 30, 2017 at 7:34	comment	added	user35593		Writing A=UV' with U,V in R^(n×k) and interpring the rows of U as linear forms and the rows of V as vectors. Then the question is equivalent of asking if there exists n hyperplanes in R^k a1,...,an and n points v1,...,vn in R^k such that vi is not on ai for all i and vi is on aj or vj on ai for any pair (i,j). I.e. we have a incidence graph problem. The following article might therefore be interesting sciencedirect.com/science/article/pii/S092577210200127X
May 22, 2017 at 4:30	answer	added	user35593		timeline score: 2
May 18, 2017 at 21:45	answer	added	Markus Sprecher		timeline score: 10
May 13, 2017 at 23:54	comment	added	Max Alekseyev		It may be worth to notice that $A+A^T$ is a symmetric matrix, and $\rk(A)\geq \frac{1}{2}\rk(A+A^T)$.
May 12, 2017 at 9:50	history	asked	Seva	CC BY-SA 3.0