The endpoint problem for $\epsilon$-hypercyclicity

Vinícius V. Fávaro, Geivison Ribeiro, Daniel Pellegrino +1

For a fixed $0<\epsilon <1$, F. Bayart asked in 2024 whether there exists an operator $T$ such that, for every $0<\delta <1$, $T$ is $\delta$-hypercyclic if and only if $δ\in[\varepsilon,1)…