scholarly journals A Short Return to Simple Ah-Algebras with Real Rank Zero

2014 ◽  
Vol 114 (2) ◽  
pp. 264
Author(s):  
Huaxin Lin
Keyword(s):  
Stable Rank ◽  
Real Rank ◽  
Real Rank Zero ◽  
Rank Zero ◽  
Rank One ◽  
Tracial Rank ◽  
Unital Simple

Let $A$ be a unital simple AH-algebra with stable rank one and real rank zero such that $kx=0$ for all $x\in\operatorname{ker}\rho_A$, the subgroup of infinitesmal elements in $K_0(A)$, and for the same integer $k\ge 1$. We show that $A$ has tracial rank zero and is isomorphic to a unital simple AH-algebra with no dimension growth.

Ideal Structure of Multiplier Algebras of Simple C*-algebras With Real Rank Zero

2001 ◽  
Vol 53 (3) ◽  
pp. 592-630 ◽  
Author(s):  
Francesc Perera
Keyword(s):  
Stable Rank ◽  
Real Rank ◽  
Ideal Structure ◽  
Real Rank Zero ◽  
Von Neumann ◽  
Rank Zero ◽  
Rank One ◽  
A Chain ◽  
Multiplier Algebras ◽  
The Ideal

AbstractWe give a description of the monoid of Murray-von Neumann equivalence classes of projections for multiplier algebras of a wide class of σ-unital simple C*-algebras A with real rank zero and stable rank one. The lattice of ideals of this monoid, which is known to be crucial for understanding the ideal structure of themultiplier algebra , is therefore analyzed. In important cases it is shown that, if A has finite scale then the quotient of modulo any closed ideal I that properly contains A has stable rank one. The intricacy of the ideal structure of is reflected in the fact that can have uncountably many different quotients, each one having uncountably many closed ideals forming a chain with respect to inclusion.

Tracially Quasidiagonal Extensions

2003 ◽  
Vol 46 (3) ◽  
pp. 388-399 ◽  
Author(s):  
Huaxin Lin
Keyword(s):  
Exact Sequence ◽  
Short Exact Sequence ◽  
Real Rank ◽  
Real Rank Zero ◽  
Rank Zero ◽  
Tracial Topological Rank ◽  
Unital Simple ◽  
Quasidiagonal Extension

AbstractIt is known that a unital simple C*-algebra A with tracial topological rank zero has real rank zero. We show in this note that, in general, there are unital C*-algebras with tracial topological rank zero that have real rank other than zero.Let 0 → J → E → A → 0 be a short exact sequence of C*-algebras. Suppose that J and A have tracial topological rank zero. It is known that E has tracial topological rank zero as a C*-algebra if and only if E is tracially quasidiagonal as an extension. We present an example of a tracially quasidiagonal extension which is not quasidiagonal.

Homomorphisms From C(X) Into C*-Algebras

1997 ◽  
Vol 49 (5) ◽  
pp. 963-1009 ◽  
Author(s):  
Huaxin Lin
Keyword(s):  
Real Rank ◽  
Real Rank Zero ◽  
Rank Zero ◽  
C Algebra ◽  
C Algebras ◽  
Finite Dimensional ◽  
Countable Rank ◽  
Rank One ◽  
Dimensional Range

AbstractLet A be a simple C*-algebra with real rank zero, stable rank one and weakly unperforated K0(A) of countable rank. We show that a monomorphism Φ: C(S2) → A can be approximated pointwise by homomorphisms from C(S2) into A with finite dimensional range if and only if certain index vanishes. In particular,we show that every homomorphism ϕ from C(S2) into a UHF-algebra can be approximated pointwise by homomorphisms from C(S2) into the UHF-algebra with finite dimensional range.As an application, we show that if A is a simple C*-algebra of real rank zero and is an inductive limit of matrices over C(S2) then A is an AF-algebra. Similar results for tori are also obtained. Classification of Hom (C(X), A) for lower dimensional spaces is also studied.

scholarly journals Strict Comparison of Positive Elements in Multiplier Algebras

2017 ◽  
Vol 69 (02) ◽  
pp. 373-407 ◽  
Author(s):  
Victor Kaftal ◽  
Ping Wong Ng ◽  
Shuang Zhang
Keyword(s):  
Positive Element ◽  
Real Rank ◽  
Real Rank Zero ◽  
Multiplier Algebra ◽  
Rank Zero ◽  
C Algebra ◽  
Positive Elements ◽  
Rank One ◽  
Multiplier Algebras ◽  
Positive Linear Combination

AbstractMain result: If a C*-algebrais simple,σ-unital, hasfinitely many extremal traces, and has strict comparison of positive elements by traces, then its multiplier algebraalso has strict comparison of positive elements by traces. The same results holds if finitely many extremal traces is replaced byquasicontinuous scale. A key ingredient in the proof is that every positive element in the multiplier algebra of an arbitrary σ-unital C* -algebra can be approximated by a bi-diagonal series. As an application of strict comparison, ifis a simple separable stable C* -algebra with real rank zero, stable rank one, and strict comparison of positive elements by traces, then whether a positive element is a positive linear combination of projections is determined by the trace values of its range projection.

scholarly journals AF FLOWS AND CONTINUOUS SYMMETRIES

2001 ◽  
Vol 13 (12) ◽  
pp. 1505-1528 ◽  
Author(s):  
O. BRATTELI ◽  
A. KISHIMOTO
Keyword(s):  
Symmetry Breaking ◽  
Fixed Points ◽  
Automorphism Groups ◽  
Real Rank ◽  
Continuous Symmetry ◽  
Real Rank Zero ◽  
Rank Zero ◽  
Finite Dimensional ◽  
Continuous Symmetries ◽  
Unital Simple

We consider AF flows, i.e. one-parameter automorphism groups of a unital simple AF C*-algebra which leave invariant the dense union of an increasing sequence of finite-dimensional *-subalgebras, and derive two properties for these; an absence of continuous symmetry breaking and a kind of real rank zero property for the almost fixed points.

scholarly journals Tracial Rokhlin property for automorphisms on simple -algebras

2008 ◽  
Vol 28 (4) ◽  
pp. 1215-1241
Author(s):  
HUAXIN LIN ◽  
HIROYUKI OSAKA
Keyword(s):  
Metric Space ◽  
Crossed Product ◽  
Real Rank ◽  
Compact Metric Space ◽  
Real Rank Zero ◽  
Rank Zero ◽  
Simple Algebras ◽  
Minimal Homeomorphisms ◽  
Unital Simple ◽  
Tracial Rokhlin Property

AbstractLet A be a unital simple $A\mathbb {T}$-algebra of real rank zero. Given an isomorphismγ1:K1(A)→K1(A), we show that there is an automorphism α:A→A such that α*1=γ1 and α has the tracial Rokhlin property. Consequently, the crossed product $A\rtimes _{\alpha }\mathbb {Z}$ is a simple unital AH-algebra with real rank zero. We also show that automorphisms with the Rokhlin property can be constructed from minimal homeomorphisms on a connected compact metric space.

The Structure of Positive Elements for C*-Algebras with Real Rank Zero

1997 ◽  
Vol 08 (03) ◽  
pp. 383-405 ◽  
Author(s):  
Francesc Perera
Keyword(s):  
Grothendieck Group ◽  
Real Rank ◽  
Real Rank Zero ◽  
Rank Zero ◽  
C Algebra ◽  
C Algebras ◽  
Positive Elements ◽  
Riesz Decomposition ◽  
Riesz Decomposition Properties ◽  
Rank One

In this paper we give a representation theorem for the Cuntz monoid S(A) of a σ-unital C*-algebra A with real rank zero and stable rank one, which allows to prove several Riesz decomposition properties on the monoid. As a consequence, it is proved that the comparability conditions (FCQ), stable (FCQ) and (FCQ+) are equivalent for simple C*-algebras with real rank zero. It is also shown that the Grothendieck group [Formula: see text] of S(A) is a Riesz group, and lattice-ordered under some additional assumptions on A.

scholarly journals Closed Convex Hulls of Unitary Orbits in Certain Simple Real Rank Zero C* -algebras

2017 ◽  
Vol 69 (5) ◽  
pp. 1109-1142 ◽  
Author(s):  
P.W. Ng ◽  
P. Skoufranis
Keyword(s):  
Upper Bound ◽  
Convex Combination ◽  
Convex Hulls ◽  
Real Rank ◽  
Real Rank Zero ◽  
Rank Zero ◽  
C Algebras ◽  
Rank One ◽  
Adjoint Operators ◽  
Tracial States

AbstractIn this paper, we characterize the closures of convex hulls of unitary orbits of self-adjoint operators in unital, separable, simple C* -algebras with non-trivial tracial simplex, real rank zero, stable rank one, and strict comparison of projections with respect to tracial states. In addition, an upper bound for the number of unitary conjugates in a convex combination needed to approximate a self-adjoint are obtained.

Sign in / Sign up

Export Citation Format

Share Document