Ideal $F$-norms on $C^*$-algebras
Izvestiâ vysših učebnyh zavedenij. Matematika, no. 5 (2015), pp. 69-74
Voir la notice de l'article provenant de la source Math-Net.Ru
We show that every noncompactness measure on a $W^*$-algebra is an ideal $F$-pseudonorm. We establish the criterion of right Fredholm property of an element with respect to $W^*$-algebra. We prove that the element $-I$ realizes maximum distance from the positive element to the subset of all isometries of unital $C^*$-algebra, here $I$ is the unit of $C^*$-algebra. We also consider differences of two finite products of elements from the unit ball of $C^*$-algebra and obtain an estimate of their ideal $F$-pseudonorms. The paper is concluded with the convergence criterion in complete ideal $F$-norm for two series of elements from $W^*$-algebra.
Keywords:
$C^*$-algebra, $W^*$-algebra, trace, Hilbert space, linear operator, Fredholm operator, isometry, unitary operator, compact operator, ideal, ideal $F$-norm, measure of noncompactness.
@article{IVM_2015_5_a7,
author = {A. M. Bikchentaev},
title = {Ideal $F$-norms on $C^*$-algebras},
journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
pages = {69--74},
publisher = {mathdoc},
number = {5},
year = {2015},
language = {ru},
url = {http://geodesic.mathdoc.fr/item/IVM_2015_5_a7/}
}
A. M. Bikchentaev. Ideal $F$-norms on $C^*$-algebras. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 5 (2015), pp. 69-74. http://geodesic.mathdoc.fr/item/IVM_2015_5_a7/