Coarse topological transitivity on open cones and coarsely J-class and D-class operators

TL;DR

This paper extends the concept of coarse hypercyclicity to coarse topological transitivity on open cones, introduces coarsely J-class and D-class operators, and explores their properties and examples in Banach spaces.

Contribution

It generalizes coarse hypercyclicity to open cones, introduces coarsely J-class and D-class operators, and provides new examples and non-existence results for these classes.

Findings

Coarse hypercyclicity implies hypercyclicity on open cones.

Coarsely topologically transitive operators are topologically transitive.

Existence of coarsely J-class and D-class operators in specific Banach spaces.

Abstract

We generalize the concept of coarse hypercyclicity, introduced by Feldman in \cite{Fe1}, to that of coarse topological transitivity on open cones. We show that a bounded linear operator acting on an infinite dimensional Banach space with a coarsely dense orbit on an open cone is hypercyclic and a coarsely topologically transitive (mixing) operator on an open cone is topologically transitive (mixing resp.). We also "localize" these concepts by introducing two new classes of operators called coarsely $J$-class and coarsely $D$-class operators and we establish some results that may make these classes of operators potentially interesting for further studying. Namely, we show that if a backward unilateral weighted shift on $l^2(\mathbb{N})$ is coarsely $J$-class (or $D$-class) on an open cone then it is hypercyclic. Then we give an example of a bilateral weighted shift on $l^{\infty}(\mathbb{Z})$ which is coarsely $J$-class, hence it is coarsely $D$-class, and not $J$-class. Note that, concerning the previous result, it is well known that the space $l^{\infty}(\mathbb{Z})$ does not support $J$-class bilateral weighted shifts, see \cite{CosMa2}. Finally, we show that there exists a non-separable Banach space which supports no coarsely $D$-class operators on open cones. Some open problems are added.