Dynamical Equivalences and Coronas
by
Igor Protasov

For every infinite discrete group G, the remainder G^*=bG\G of the Stone-Cech compactification bG of G has a natural structure of G-space. The orbit equivalence on G^* determines the smallest by inclusion, closed in G^*×G^* equivalence ~ containing the orbit equivalence, and factor-space nG=G^*/ ~ is called the corona of G. I am going (following [1], [2]) to talk over relationships between bG (as a right topological semigroup) and nG.

1. I.V.Protasov, Coronas of balleans, Topol. Appl., 149 (2005), 149-160.
2. I. Protasov, Dynamical equivalences on G^*, Topol. Appl. (2008), on-line.

Date received: June 18, 2008