107 citations · 419 across the 18 of their papers we have counts for
Showing math.OCShow all
2 papers · 1 filter
math.OC2026
Riccati Stability Without Auxiliary Matrices
Jeffrey Humpherys
In the 2004 collection \emph{Unsolved Problems in Mathematical Systems and Control Theory}, Erik Verriest posed the problem of characterizing Riccati stability ``without invoking a…
math.OC2026
The De Cock--De Moor Conjecture: Proof, Normal Form, and Indefinite Angles
Jeffrey Humpherys
De Cock and De Moor conjectured that two matrices built from the solutions of three coupled Lyapunov equations always share their eigenvalues, an identity linking principal angles…