Multi-orbital frames through model spaces

Carlos Cabrelli, Ursula Molter, Daniel Suárez

We characterize the normal operators $A$ on ${\ell }^2$ and the elements $a^i\in {\ell }^2$, with $1\le i\le m$, such that the sequence $$\{A^n{a}^1,\dots ,A^n{a}^m{\}}_{n\ge 0}$$ is…