Zobrazeno 1 - 10
of 147
pro vyhledávání: '"Hatori, Osamu"'
Autor:
Abe, Toshikazu, Hatori, Osamu
We revise a proof of a Mazur-Ulam theorem for generalized gyrovector spaces.
Comment: 13 pages
Comment: 13 pages
Externí odkaz:
http://arxiv.org/abs/2403.15015
Autor:
Hatori, Osamu, Oi, Shiho
We study maps between positive definite or positive semidefinite cones of unital $C^*$-algebras. We describe surjective maps that preserve (1) the norm of the quotient or multiplication of elements; (2) the spectrum of the quotient or multiplication
Externí odkaz:
http://arxiv.org/abs/2403.07341
Autor:
Hatori, Osamu, Oi, Shiho
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 are topologically isomorphic. We describe the structure of isometric rea
Externí odkaz:
http://arxiv.org/abs/2312.11827
Autor:
Hatori, Osamu
We study $C$-rich spaces, lush spaces, and $C$-extremely regular spaces concerning with the Mazur-Ulam property. We show that a uniform algebra and the real part of a uniform algebra with the supremum norm are $C$-rich spaces, hence lush spaces. We p
Externí odkaz:
http://arxiv.org/abs/2205.01888
Autor:
Hatori, Osamu
We give a sufficient condition for a Banach space with which the homogeneous extension of a surjective isometry from the unit sphere of it onto another one is real-linear. The condition is satisfied by a uniform algebra and a certain extremely $C$-re
Externí odkaz:
http://arxiv.org/abs/2107.01515
We prove that a surjective isometry between the unit spheres of two uniform algebras is extended to a surjective real-linear isometry between the uniform algebras. It provides the first positive solution for Tingley's problem on a Banach space of ana
Externí odkaz:
http://arxiv.org/abs/2101.01994
Autor:
Hatori, Osamu, Oi, Shiho
We study 2-local reflexivity of the set of all surjective isometries between certain function spaces. We do not assume linearity for isometries. We prove that a 2-local isometry in the group of all surjective isometries on the algebra of all continuo
Externí odkaz:
http://arxiv.org/abs/1812.10342
Autor:
Hatori, Osamu
We propose a unified approach to the study of isometries on algebras of vector-valued Lipschitz maps and those of continuously differentiable maps by means of the notion of natural $C(Y)$-valuezations that take values in unital commutative $C^*$-alge
Externí odkaz:
http://arxiv.org/abs/1803.08236
Autor:
Hatori, Osamu, Oi, Shiho
We propose a unified approach to the study of isometries on algebras of vector-valued Lipschitz maps and those of continuously differentiable maps by means of the notion of admissible quadruples. We describe isometries on function spaces of some admi
Externí odkaz:
http://arxiv.org/abs/1709.05782
Autor:
Abe, Toshikazu, Hatori, Osamu
We give a revision of the proof of a Mazur-Ulam theorem for generalized gyrovector spaces given in the paper "Generalized gyrovector spaces and a Mazur-Ulam theorem" published in Publ. Math. Debrecen, 87 (2015), 393--413.
Comment: revised
Comment: revised
Externí odkaz:
http://arxiv.org/abs/1511.05187