Asymptotic homomorphisms into the Calkin algebra ∗
نویسنده
چکیده
Let A be a separable C∗-algebra and let B be a stable C∗-algebra with a strictly positive element. We consider the (semi)group Ext(A,B) (resp. Ext(A,B)) of homotopy classes of asymptotic (resp. of genuine) homomorphisms from A to the corona algebra M(B)/B and the natural map i : Ext(A,B) −→ Ext(A,B). We show that if A is a suspension then Ext(A,B) coincides with E-theory of Connes and Higson and the map i is surjective. In particular any asymptotic homomorphism from SA to M(B)/B is homotopic to some genuine homomorphism.
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