Timeline for Null space vs. semi-positive definite matrix

12 events

when toggle format	what		by	license	comment
Jun 20, 2012 at 20:42	vote	accept	user24579
Jun 20, 2012 at 20:41	vote	accept	user24579
Jun 20, 2012 at 20:42
Jun 20, 2012 at 20:41	vote	accept	user24579
Jun 20, 2012 at 20:41
Jun 20, 2012 at 20:41	vote	accept	user24579
Jun 20, 2012 at 20:41
Jun 20, 2012 at 20:38	vote	accept	user24579
Jun 20, 2012 at 20:41
Jun 20, 2012 at 15:45	answer	added	Jan Jitse Venselaar		timeline score: 1
Jun 20, 2012 at 14:25	history	edited	François G. Dorais		edited tags
Jun 20, 2012 at 12:26	comment	added	user24579		Non-negative definite is equivalent to semi-positive definite, i.e., I would like to know if for an arbitrary vector $q$ , the following relation holds: $q^T(I-J^{\#} J)q \ge 0$
Jun 20, 2012 at 11:56	answer	added	Denis Serre		timeline score: 0
Jun 20, 2012 at 10:14	comment	added	Denis Serre		The matrix $\left(I - J^\# J \right)$ is that of the projection onto $R(M^{-1}J^T)$, parallel to $\ker J$. It is not Hermitian, unless $R(J^T)$ (or equivalently $\ker J$) be stable under $M$. So, what do you mean by being non-negative definite ?
Jun 20, 2012 at 9:45	history	edited	user24579	CC BY-SA 3.0	added 14 characters in body
Jun 20, 2012 at 9:24	history	asked	user24579	CC BY-SA 3.0