Results 61 to 70 of about 54,491 (191)

Spatial numerical ranges of elements of Banach algebras

International Journal of Mathematics and Mathematical Sciences, 1989
In this paper, the notion of spatial numerical range of elements of Banach algebras without identity is studied. Specifically, the relationship between spatial numerical ranges, numerical ranges and spectra is investigated.
A. K. Gaur, T. Husain
doaj   +1 more source

Unitarily invariant valuations on convex functions

Journal of the London Mathematical Society, Volume 113, Issue 4, April 2026.
Abstract Continuous, dually epi‐translation invariant valuations on the space of finite‐valued convex functions on Cn$\mathbb {C}^n$ that are invariant under the unitary group are investigated. It is shown that elements belonging to the dense subspace of smooth valuations admit a unique integral representation in terms of two families of Monge–Ampère ...
Jonas Knoerr
wiley   +1 more source

Approximate Biprojectivity of ℓ1-Munn Banach Algebras

Journal of Mathematics, 2022
In the present paper, we study the approximate biprojectivity and weak approximate biprojectivity of ℓ1-Munn Banach algebras when the related sandwich matrix is regular over InvA.
G. Zarei, A. Pourabbas, M. Rostami, A. Sahami   +3 more
doaj   +1 more source

Quotients of Local Banach Algebras are Local Banach Algebras

Publications of the Research Institute for Mathematical Sciences, 1991
We show that quotients of local Banach algebras are local Banach algebras. This solves a problem posed by B. Blackadar in his book on K -Theory [BLA1]. Furthermore our techniques allow to prove additional density Theorems for the K -Theory of normed ...
openaire   +2 more sources

ωℒ{\omega }_{{\mathcal{ {\mathcal L} }}}-biprojective and ω¯\overline{\omega }-contractible Banach algebras

Demonstratio Mathematica
For a given Banach algebra ℳ{\mathcal{ {\mathcal M} }} and a continuous endomorphism ω\omega on ℳ{\mathcal{ {\mathcal M} }}, we define ℳ{\mathcal{ {\mathcal M} }} to be ωℒ{\omega }_{{\mathcal{ {\mathcal L} }}}-biprojective and ω¯\overline{\omega ...
Ghorbani Zahra
doaj   +1 more source

On $p$-convexification of the Banach-Kantorovich lattice [PDF]

E-Journal of Analysis and Applied Mathematics
Let $B$ be a complete Boolean algebra, $Q(B)$ the Stone compact of $B$, and let $C_\infty (Q(B))$ be the commutative unital algebra of all continuous functions $x: Q(B) \to [-\infty, +\infty]$, assuming possibly the values $\pm\infty$ on nowhere-dense ...
Gavhar B. Zakirova
doaj   +1 more source

Exact local distribution of the absolutely continuous spectral measure

Proceedings of the London Mathematical Society, Volume 132, Issue 4, April 2026.
Abstract It is well‐established that the spectral measure for one‐frequency Schrödinger operators with Diophantine frequencies exhibits optimal 1/2$1/2$‐Hölder continuity within the absolutely continuous spectrum (Avila and Jitomirskaya, Commun. Math. Phys. 301 (2011), 563–581).
Xianzhe Li, Jiangong You, Qi Zhou
wiley   +1 more source

On the ideals of extended quasi-nilpotent Banach algebras

International Journal of Mathematics and Mathematical Sciences, 1991
Given a quasi-nilpotent Banach algebra A, we will use the results of Seddighin [2], to study the properties of elements which belong to a proper closed two sided ideal of A¯ and A¯¯. Here A¯ is the extension of A to a Banach Algebra with identity.
Morteza Seddighin
doaj   +1 more source

Duality for Evolutionary Equations With Applications to Null Controllability

Mathematical Methods in the Applied Sciences, Volume 49, Issue 5, Page 4144-4166, 30 March 2026.
ABSTRACT We study evolutionary equations in exponentially weighted L2$$ {\mathrm{L}}^2 $$‐spaces as introduced by Picard in 2009. First, for a given evolutionary equation, we explicitly describe the ν$$ \nu $$‐adjoint system, which turns out to describe a system backwards in time. We prove well‐posedness for the ν$$ \nu $$‐adjoint system. We then apply
Andreas Buchinger, Christian Seifert
wiley   +1 more source