Let $(a_n)$ be a sequence of bounded operators on $\ell_2$ such that $\lim_n\sup_i\Vert a_n\xi_i\Vert\to 0$ for every orthonormal system $(\xi_i)$ in $\ell_2$.
Is $(a_n)$ necessarily a norm-null sequence?
2026-04-06 17:19:52.1775495992
Norm-null sequence of operators
53 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in OPERATOR-THEORY
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