Abstract: | In this paper we extend to C*-algebras and to von Neumann algebras some results on approximants that have previously been found in the context of $
\mathcal{L}
$
\mathcal{L}
(H) and of the von Neumann-Schatten classesC
p
, 1⩽ p <∞. We obtain results concerning positive approximants, unitary and partially isometric approximants and commutator approximants;
and we study paranormality. Our main tools are the Gelfand-naimark Theorem and Berntzen’s results on normal spectral approximation. |