A note on disjoint hypercyclicity for invertible bilateral pseudo-shifts on $\ell^{p}(\mathbb{Z})$
SongUng Ri, HyonHui Ju, JinMyong Kim
TL;DR
This paper investigates disjoint hypercyclicity for invertible bilateral pseudo-shifts on $\ell^{p}(\mathbb{Z})$, showing that invertibility does not preclude disjoint hypercyclicity and even allowing both an operator and its inverse to be jointly disjoint hypercyclic. It introduces a Disjoint Blow-up/Collapse Criterion to establish disjoint hypercyclicity for a family of bilateral pseudo-shifts and provides explicit invertible examples, including constructions not reducible to powers of bilateral weighted shifts. It also resolves a question about reiterative hypercyclicity on reflexive Banach spaces by proving the equivalence between disjoint hypercyclicity and disjoint reiterative hypercyclicity under reiterative hypercyclicity, and extends results to $\ell^{p}$-spaces with $p>1$ without the same inducing map condition. The results broaden the known dynamics of pseudo-shifts beyond weighted shifts and contribute to the understanding of joint dynamical properties in Banach spaces, with implications for open problems in disjoint (reiterative) hypercyclicity.
Abstract
We first give a note on disjoint hypercyclicity for invertible bilateral pseudo-shifts on $\ell^{p}(\mathbb{Z})$, $1\leq p <\infty$. It is already known that if a tuple of bilateral weighted shifts on $\ell^{p}(\mathbb{Z})$, $1\leq p <\infty$, is disjoint hypercyclic, then non of the weighted shifts is invertible. We show that as for pseudo-shifts which is a generalization of weighted shifts, this fact is not true. We give an example of invertible bilateral pseudo-shifts on $\ell^{p}(\mathbb{Z})$, $1\leq p <\infty$, which are disjoint hypercyclic and whose inverses are also disjoint hypercyclic. Next we partially answer to the open problem posed by Martin, Menet and Puig (2022)\cite{MMP22} concerned with disjoint reiteratively hypercyclic, that is, we show that as for the operators on a reflexive Banach space, reiteratively hypercyclic ones are disjoint hypercyclic if and only if they are disjoint reiteratively hypercyclic.
