 

Gábor Braun
Characterization of matrix types of ultramatricial algebras


Published: 
January 31, 2005

Keywords: 
matrix type of a ring; dimension group; ultramtaricial algebra; automorphism group of a dimension group 
Subject: 
Primary 20K30, 16S50; Secondary 06F20, 19A49 


Abstract
For any equivalence relation ≡ on positive integers such that nk ≡ mk if and
only if n ≡ m, there is an abelian group G such that the
endomorphism ring of G^{n} and G^{m} are isomorphic if and only if n ≡
m. However, G^{n} and G^{m} are not isomorphic if n ≠ m.


Author information
Alfréd Rényi Institute of Mathematics, Hungarian Academy of Sciences, Budapest, Reáltanoda u 1315, 1053, Hungary
braung@renyi.hu

