Lie Triple Derivations on von Neumann Algebras

Let A be a von Neumann algebra with no central abelian projections. It is proved that if an additive map δ :A → A satisfies δ([[a, b], c]) = [[δ(a), b], c] + [[a, δ(b)], c] +[[a, b], δ(c)] for any a, b, c∈ A with ab = 0(resp. ab = P, where P is a fixed nontrivial projection in A), then there exist an additive derivation d from A into itself and an additive map f :A → ZA vanishing at every second commutator [[a, b], c] with ab = 0(resp.ab = P) such that δ(a) = d(a) + f(a) for any a∈ A.     

Minimal invariant varieties and first integrals for algebraic foliations

Let X be an irreducible algebraic variety over ℂ, endowed with an algebraic foliation . In this paper, we introduce the notion of minimal invariant variety V( , Y) with respect to ( , Y), where Y is a subvariety of X. If Y = {x} is a smooth point where the foliation is regular, its minimal invariant variety is simply the Zariski closure of the leaf passing through x. First we prove that for very generic x, the varieties V( , x) have the same dimension p. Second we generalize a result due to X. Gomez- Mont (see [G-M]). More precisely, we prove the existence of a dominant rational map F : X → Z, where Z has dimension (n − p), such that for very generic x, the Zariski closure of F⁻¹(F(x)) is one and only one minimal invariant variety of a point. We end up with an example illustrating both results.     

δ-Hom-Jordan Lie superalgebras

This paper is primarily concerned with δ-Hom-Jordan Lie superalgebras. We discuss the concepts of α^k-derivations, representations and T*-extensions of δ-Hom-Jordan Lie superalgebras in detail, and some cohomological characterizations are established.     

Derivations of the Lie algebra of infinite strictly upper triangular matrices over a commutative ring

Let 𝒩(∞,R) be the Lie algebra of infinite strictly upper triangular matrices over a commutative ring R. We show that every derivation of 𝒩(∞,R) is a sum of diagonal and inner derivations.     

标准算子代数上满足某些等式的广义导子的刻画(英文)

令H为复数域C上的Hilbert空间,A为H上的标准算子代数.设δ:A→B(H)是线性映射.本文证明了,如果对任意A∈A成立δ(AA~*A)=δ(A)A~*A-Aδ(A~*)A+AA~*δ(A),则存在λ∈C及算子S,T∈B(H)满足S+T=λI,使得对所有的A∈A都有δ(A)=SA-AT.     

Real hypersurfaces in complex space forms concerned with the local symmetry

This paper consists of two parts. In the first, we find some geometric conditions derived from the local symmetry of the inverse image by the Hopf fibration of a real hypersurface M in complex space form M _m(4ε). In the second, we give a complete classification of real hypersurfaces in M _m(4ε) which satisfy the above geometric facts. The second author was supported by DGICYT research project BFM 2001-2871-C04-01 and the first and the third authors were supported by grant Proj. No. R14-2002-003-01001-0 from Korea Research Foundation, Korea 2006.     

Non-reflexivity of the derivation space from Banach algebras of analytic functions

Let be an open connected subset of the plane, and let be a Banach algebra of analytic functions on . We show that the space of bounded derivations from into is not reflexive. We also obtain similar results when for .

     

Non-commutative Arens algebras and their derivations

Given a von Neumann algebra M with a faithful normal semi-finite trace τ, we consider the non-commutative Arens algebra Lω(M,τ)=_?p?1Lp(M,τ) and the related algebras and which are proved to be complete metrizable locally convex *-algebras. The main purpose of the present paper is to prove that any derivation of the algebra is inner and all derivations of the algebras Lω(M,τ) and are spatial and implemented by elements of . In particular we obtain that if the trace τ is finite then any derivation on the non-commutative Arens algebra Lω(M,τ) is inner.     

环上可加左导子的刻画

令A与B是含单位元的环,M是(A,B)-双模,U=Tri(A,M,B)是三角环.在一些附加假设条件下,本文从几个不同的角度给出了U上可加左导子的结构性质.此外,也得到了满足一定条件的环上可加左导子的两个不同刻画.