RT Journal Article T1 Propiedades en norma de los operadores en relación con la sumabilidad absoluta en el espacio de Hilbert A1 Martín Peinador, Elena AB Let B(H) be the algebra of all bounded linear operators acting on the real separable Hilbert space H and let S={an}∞n=1 be a sequence in H. Consider the linear manifolds CS={AB(H):∑∞n=1||Aan||<∞}and DS={AB(H):{Aan}∞n=1 is summable} of B(H), and MS={xH:∑∞ n=1|(an,x)|<∞} of H. The author proves that CS is not closed, in general, and characterizes the cases when CS is closed in terms of the domain of weak summability of S. If dimMS is finite, or dim(linear spanS) is finite, then CS=DS, but the converse is false. PB Real Sociedad Matemática Española;Consejo Superior de Investigaciones Científicas. Instituto "Jorge Juan" de Matemáticas SN 0373-0999 YR 1978 FD 1978 LK https://hdl.handle.net/20.500.14352/64849 UL https://hdl.handle.net/20.500.14352/64849 DS Docta Complutense RD 1 may 2024