This paper among the top 10 most downloaded papers of Journal of Functional Analysis in the next 5 years after publication.
Let ${T_t}_{t\ge 0}$ be a hypercyclic strongly continuous semigroup of operators. Then each operator $T_t$ is hypercyclic as a single operator, and it shares the set of hypercyclic vectors with the semigroup. This answers in the affirmative a natural question concerning hypercyclic C0-semigroups. The analogous result for frequent hypercyclicity is also obtained. (This result is also known as the Conejero-Müller-Peris theorem in linear dynamics and generalizes and complete a previous result of Oxtoby and Ulam in Annals of Mathematics from 1941.
J.A. Conejero, V. Müller, and A. Peris. Hypercyclic behaviour of operators in a hypercyclic C0-semigroup. J. Funct. Anal. 244(1), 342-348, 2007. doi:10.1016/j.jfa.2006.12.008