4 citations · 5 across the 11 of their papers we have counts for
10 papers · 1 filter
Surjective Fischer--Muszély maps on positive cones of JB-algebras
Osamu Hatori, Shiho Oi
We prove that every surjective Fischer--Muszély map between positive cones of arbitrary JB-algebras is additive and positively homogeneous, and extends uniquely to a bounded positi…
Linear maps preserving -symmetry operators
Mayu Anzai, Shiho Oi
Let be a separable complex Hilbert space. In this paper, we study a continuous bijective linear map on the algebra of all bounded linear operators on . We characterize t…
Spectral decomposition of doubly power-bounded elements in Banach algebras
Osamu Hatori, Shiho Oi
We establish a characterization of doubly power-bounded elements with finite spectrum in Banach algebras. In particular, we present a spectral decomposition for such elements, exte…
Spectrally additive maps on the positive cones of the Wiener algebra
Shiho Oi, Kaito Sato
We study surjective maps between the positive cones of the Wiener algebra that preserve the spectrum of the sum of every two elements. We show that such maps can be extended to iso…
Spectral decomposition of power-bounded operators: The finite spectrum case
Shiho Oi, Jyamira Oppekepenguin
In this paper, we investigate power-bounded operators, including surjective isometries, on Banach spaces. Koehler and Rosenthal asserted that an isolated point in the spectrum of a…
Isometries between groups of invertible elements in Fourier-Stieltjes algebras
Osamu Hatori, Shiho Oi
We prove that if open subgroups of the groups of invertible elements in two Fourier-Stieltjes algebras are isometric as metric spaces, then the underlying locally compact groups ar…