Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Extensions of Quasidiagonal C*-algebras and K-theory   We study the extension problem for quasidiagonal (QD) C*-algebras (i.e. when
is an extension of QD C*-algebras again QD?). The main positive result states
that in many instances an extension will remain QD provided that a certain
boundary arising from the K-theory of the extension vanishes. A K-theoretic
Hahn-Banach type property is also introduced for QD C*-algebras. We show that
every nuclear QD C*-algebra has this Hahn-Banach property if and only if the
extension problem for many QD C*-algebras is completely determined by a
boundary map on K-theory.

12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin