 

Mark Tomforde
Ext Classes and Embeddings for C*Algebras of Graphs with Sinks


Published: 
November 10, 2001 
Keywords: 
CuntzKrieger algebra, graph algebra, 1sink extension, CKequivalence, C*algebra 
Subject: 
19K33 and 46L55 


Abstract
We consider directed graphs E
obtained by adding a sink to a fixed graph G.
We associate an element of Ext(C*(G)) to each such E,
and show that the classes of two such graphs are equal in
Ext(C*(G)) if and only if the associated C*algebra
of one can be embedded as a full corner in the
C*algebra of the other in a particular way. If every
loop in G has an exit, then we are able to use this
result to generalize some known classification
theorems for C*algebras of graphs with sinks.


Author information
Department of Mathematics, Dartmouth College, Hanover, NH 037553551, USA
mark.tomforde@dartmouth.edu

