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Apr 20, 2023 at 19:09 vote accept jay
Nov 6, 2018 at 2:37 comment added Brendan McKay Take $A=I$ and recall that any psd matrix can be written as $B^TB$.
Nov 6, 2018 at 1:38 history edited jay CC BY-SA 4.0
edited title
S Nov 6, 2018 at 1:37 history suggested David G. Stork CC BY-SA 4.0
Simple MathJax
Nov 5, 2018 at 22:21 review Suggested edits
S Nov 6, 2018 at 1:37
Nov 5, 2018 at 21:04 answer added Suvrit timeline score: 7
Nov 5, 2018 at 20:57 comment added Alex M. @JayStanley: "Bounding the eigenvalues of $BAB^T$ with $A$" does not seem fixed to me; it simply makes no sense in English.
Nov 5, 2018 at 20:26 comment added jay @AlexM. I fixed the title. PSD means positive semi definite.
Nov 5, 2018 at 20:20 history edited jay CC BY-SA 4.0
edited title
Nov 5, 2018 at 19:51 comment added Christian Remling In your second paragraph, you forgot that $B^tx$ need not have the same norm as $x$. But of course you can make trivial observations along these lines, for example if $B^t x$, $\|x\|=1$, is an eigenvector of the min ev $\lambda$ of $A$, then the smallest ev of $BAB^t$ is $\ge \lambda\|B^tx\|^2$.
S Nov 5, 2018 at 17:16 history suggested Amir Sagiv CC BY-SA 4.0
title + English + formatting + tag
Nov 5, 2018 at 16:33 comment added Nik Weaver @AlexM. surely "positive semidefinite".
Nov 5, 2018 at 16:26 comment added Alex M. Your title doesn't make sense. Also, what is PSD?
Nov 5, 2018 at 16:20 review Suggested edits
S Nov 5, 2018 at 17:16
Nov 5, 2018 at 15:20 review First posts
Nov 5, 2018 at 16:20
Nov 5, 2018 at 15:15 history asked jay CC BY-SA 4.0