COMPLETELY POSITIVE MAPS AND-ISOMORPHISM OF C-ALGEBRAS

摘要

＜正＞ Let A,B be unital C*-algebras.XA={|are all completely positive linear maps from Mn（C）to A with ‖a‖≤1}.(a=((e11)…(e1n……(en1)…(enn)),where{eiy}is the matrix unit of Mn（C）.)Let a be the natural action of SU（n）on Mn（C）.For n≥3,if Φis an a-invariant affine isomorphism between XA and XB,Φ（0）=0,then A and B are*-isomorphic.In this paper a counter example is given for the case n=2.