On Homotopy Classification of Elliptic Problems with Contractions and K-Groups of Corresponding C*-Algebras.

We consider a computation of a group of stable homotopy classes for pseudodifferential elliptic boundary problems. We study this problem in terms of topological K-groups of spaces in the following cases: boundary-value problems on manifolds with boundary, transmission problems with conditions on a closed submanifold of codimension one, and nonlocal problems with contractions. [ABSTRACT FROM AUTHOR]