Results 11 to 20 of about 131 (55)
Gysin sequences and SU(2)‐symmetries of C∗‐algebras
Transactions of the London Mathematical Society, Volume 8, Issue 1, Page 440-492, December 2021., 2021 Abstract Motivated by the study of symmetries of C∗‐algebras, as well as by multivariate operator theory, we introduce the notion of an SU(2)‐equivariant subproduct system of Hilbert spaces. We analyse the resulting Toeplitz and Cuntz–Pimsner algebras and provide results about their topological invariants through Kasparov's bivariant K‐theory.
Francesca Arici, Jens Kaad
wiley +1 more source
Journal of the London Mathematical Society, Volume 103, Issue 2, Page 633-671, March 2021., 2021 Abstract Every unitary solution of the Yang–Baxter equation (R‐matrix) in dimension d can be viewed as a unitary element of the Cuntz algebra Od and as such defines an endomorphism of Od. These Yang–Baxter endomorphisms restrict and extend to several other C∗‐ and von Neumann algebras, and furthermore define a II1 factor associated with an extremal ...
Roberto Conti, Gandalf Lechner
wiley +1 more source
Infant Mental Health Journal: Infancy and Early Childhood, Volume 42, Issue 1, Page 21-34, January/February 2021., 2021 ABSTRACT Parental reflective functioning (PRF) is an important predictor of infant attachment, and interventions that target parent–infant/toddler dyads who are experiencing significant problems have the potential to improve PRF. A range of dyadic interventions have been developed over the past two decades, some of which explicitly target PRF as part ...
Jane Barlow +2 more
wiley +1 more source
An application of the Sakai′s theorem to the characterization of H*‐algebras
International Journal of Mathematics and Mathematical Sciences, Volume 18, Issue 2, Page 317-322, 1995., 1995 The well‐known Sakai′s theorem, which states that every derivation acting on a von Neumann algebra is inner, is ,used to obtain a new elegant proof of the Saworotnow′s characterization theorem for associative H*‐algebras via two‐sided H*‐algebras. This proof completely avoids structure theory.
Borut Zalar
wiley +1 more source
Nonlinear maps preserving higher-dimensional numerical range of skew Lie product of operators
, 2016 Let k be a positive integer. Let H and K be complex Hilbert spaces of dimensions greater than k . By Wk(A) denote the k -dimensional numerical range of an operator A . In this paper we prove that a surjective map φ : B(H) → B(K) satisfies Wk(AB−BA∗) = Wk(
Chaoqun Chen, F. Lu
semanticscholar +1 more source
A note on the $C$ -numerical radius and the $\lambda$ -Aluthge transform in finite factors [PDF]
Annals of Functional Analysis, 2017 We prove that for any two elements A, B in a factor M, if B commutes with all the unitary conjugates of A, then either A or B is in CI. Then we obtain an equivalent condition for the situation that the C-numerical radius ωC(·) is a weakly unitarily ...
Xiaoyan Zhou, Junsheng Fang, Shilin Wen
semanticscholar +1 more source
On cyclic vectors and thin von Neumann algebras
Operators and Matrices, 2013 We prove that certain classes of von Neumann algebras with regular, injective subalgebras are thin. As a consequence, all Hochschild cohomology groups of these algebras are zero. Mathematics subject classification (2010): 46L10, 47A16.
Florin Pop
semanticscholar +1 more source
A note on one‐parameter groups of automorphisms
International Journal of Mathematics and Mathematical Sciences, Volume 13, Issue 1, Page 135-138, 1990., 1988 Let {αt : t ∈ R} and {βt : t ∈ R} be two commuting one‐parameter groups of ∗‐automorphisms of a von Neumann algebra M such that αt + α−t = βt + β−t for all t ∈ R. The purpose of this note is to provide a simple and short proof of the central decomposition result: αt = βt on Mp and a αt = β−t on M(1 − p) for a central projection p ∈ M, without using the
A. B. Thaheem, Noor Mohammad
wiley +1 more source
Pseudo-Diagonals and Uniqueness Theorems [PDF]
, 2013 We examine a certain type of abelian C*-subalgebra that allows one to give a unified treatment of two uniqueness theorems: for graph C*algebras and for certain reduced crossed products.
G. Nagy, Sarah Reznikoff
semanticscholar +1 more source
On the operator equation α + α−1 = β + β−1
International Journal of Mathematics and Mathematical Sciences, Volume 9, Issue 4, Page 767-770, 1986., 1986 Let α, β be ∗‐automorphisms of a von Neumann algebra M satisfying the operator equation α + α−1 = β + β−1. In this paper we use new techniques (which are useful in noncommutative situations as well) to provide alternate proofs of the results:‐ If α, β commute then there is a central projection p in M such that α = β on MP and α = β−1 on M(1 − P); If M =
A. B. Thaheem
wiley +1 more source