2 papers
math.CV2022
Alternative proofs of Mandrekar's theorem
Linus Bergqvist
We present two alternative proofs of Mandrekar's theorem, which states that an invariant subspaces of the Hardy space on the bidisc is of Beurling type precisely when the shifts sa…
math.CV2020
Rational inner functions and their Dirichlet type norms
Linus Bergqvist
We study membership of rational inner functions in Dirichlet-type spaces in polydisks. In particular, we prove a theorem relating such inclusions to integrability of partial…