Timeline for Number of perturbations of the Jordan form

4 events

when toggle format	what		by	license	comment
Jan 9, 2012 at 7:50	vote	accept	Alexander
May 30, 2012 at 14:08
Nov 26, 2011 at 14:51	comment	added	Marc van Leeuwen		@Richard: Your reply needs two corrections. First, since we say orbit $O_2$ is a perturbation of $o_1$ iff $O_1\subseteq\overline{O_2}$, you should say $\mu\geq\lambda$ in the dominance order (this takes care of OP's comment). But second, one cannot assume nilpotent matrices (or any other constant characteristic polynomial): since diagonalizable matrices are dense, one always finds the partition (1,1,\ldots,1)$ in a neigbourhood, although within the nilpotent cone it describes the smallest, closed, orbit. One can go up inside the cone, or down outside it.
Nov 25, 2011 at 5:33	comment	added	Alexander		We are working over $\mathbb{C}$.
Nov 24, 2011 at 21:48	history	answered	Richard Stanley	CC BY-SA 3.0