Results 21 to 30 of about 53 (53)

Derivations of certain operator algebras

International Journal of Mathematics and Mathematical Sciences, Volume 24, Issue 5, Page 345-349, 2000., 2000
Let 𝒩 be a nest and let 𝒜 be a subalgebra of L(H) containing all rank one operators of alg 𝒩. We give several conditions under which any derivation δ from 𝒜 into L(H) must be inner. The conditions include (1) H− ≠ H, (2) 0+ ≠ 0, (3) there is a nontrivial projection in 𝒩 which is in 𝒜, and (4) δ is norm continuous. We also give some pplications.
Jiankui Li, Hemant Pendharkar
wiley   +1 more source

On the Upper Bound of the Third Hankel Determinant for Certain Class of Analytic Functions Related with Exponential Function

Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2022
In the present paper we introduce a new class of analytic functions f in the open unit disk normalized by f(0) = f′(0)−1 = 0, associated with exponential functions.
Breaz Daniel, Cătaş Adriana, Cotîrlă Luminiţa-Ioana   +2 more
doaj   +1 more source

Absolute continuity and hyponormal operators

International Journal of Mathematics and Mathematical Sciences, Volume 4, Issue 2, Page 321-335, 1981., 1981
Let T be a completely hyponormal operator, with the rectangular representation T = A + iB, on a separable Hilbert space. If 0 is not an eigenvalue of T* then T also has a polar factorization T = UP, with U unitary. It is known that A, B and U are all absolutely continuous operators.
C. R. Putnam
wiley   +1 more source

On numerical solution of nonlinear parabolic multicomponent diffusion-reaction problems

Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2021
This work continues our previous analysis concerning the numerical solution of the multi-component mass transfer equations. The present test problems are two-dimensional, parabolic, non-linear, diffusion- reaction equations. An implicit finite difference
Juncu Gh., Popa C., Sarbu Gh.
doaj   +1 more source

Derivations and Extensions in JC‐Algebras

International Journal of Mathematics and Mathematical Sciences, Volume 2025, Issue 1, 2025.
A well‐known result by Upmeier states that every derivation on a universally reversible JC‐algebra A⊆B(H)sa extends to the C∗‐algebra [A] generated by A in B(H). In this paper, we significantly strengthen this result by proving that every Jordan derivation on a universally reversible JC‐algebra A extends to ∗‐derivations on its universal enveloping ...
Fatmah B. Jamjoom, Doha A. Abulhamail, Armando Sánchez-Nungaray   +2 more
wiley   +1 more source

m-Isometric tensor products

Concrete Operators, 2023
Given Banach space operators Si{S}_{i} and Ti{T}_{i}, i=1,2i=1,2, we use elementary properties of the left and right multiplication operators to prove, that if the tensor products pair (S1⊗S2,T1⊗T2)\left({S}_{1}\otimes {S}_{2},{T}_{1}\otimes {T}_{2}) is ...
Duggal Bhagawati Prashad, Kim In Hyoun
doaj   +1 more source

A Note on Skew Derivations and Antiautomorphisms of Prime Rings

Journal of Mathematics, Volume 2025, Issue 1, 2025.
In this article, we investigate the behavior of a prime ring which admits a skew derivation satisfying certain functional identities involving an antiautomorphism. We employ tools such as generalized identities and commutativity‐preserving maps to analyze these rings.
Faez A. Alqarni, Nadeem U. R. Rehman, Hafedh Alnoghashi, Junaid Nisar, Omar Al-Mallah, Ali Jaballah   +5 more
wiley   +1 more source

A Benchmark Generalization of Fuzzy Soft Ideals in Ordered Semigroups

Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2021
In real life, variability and inaccuracy are always presentand must be calculated by either possibilistic, probabilistic, polymorphic or other uncertainty approach. This benchmark study is about to construct new types of fuzzy soft ideals i.e., (∈, ∈ ∨qk)
Khan Faiz Muhammad, Leoreanu-Fotea Violeta, Saifullah, Amanullah   +3 more
doaj   +1 more source

Some conditions under which Jordan derivations are zero

Journal of Taibah University for Science, 2017
In the current article, we obtain the following results: Let A be an algebra and P be a semi-prime ideal of A. Suppose that d:A→(A/P) is a Jordan derivation such that dim{d(a)|a∈A}≤1. If d(P)={0}, then d is zero.
Z. Jokar, A. Hosseini, A. Niknam
doaj   +1 more source

m-isometric generalised derivations

Concrete Operators, 2022
Given Banach space operators Ai, Bi (i = 1, 2), let δi denote (the generalised derivation) δi(X) = (LAi − RBi )(X) = AiX − XBi. If 0 ∈ σa(Bi), i = 1, 2, and if Δδ1,δ2n(I)=(Lδ1Rδ1-I)n(I)=0\Delta _{{\delta _1},\delta 2}^n\left( I \right) = {\left( {{L_ ...
Duggal B.P., Kim I.H.
doaj   +1 more source