Eigenvalues and hypercyclicity in omega

Abstract

We define the class of upper staircase matrices on ω. Such matrices have a plethora of eigenvalues and eigenvectors, and they are hypercylic. We show that countably many strictly upper triangular matrices on ω which are also upper staircase have a common hypercyclic subspace. This last result partially extends a theorem of Bès and Conejero.