STRONG MORITA EQUIVALENCE OF INVERSE SEMIGROUPS

We introduce strong Morita equivalence for inverse semigroups. This notion encompasses Mark Lawson's concept of enlargement. Strongly Morita equivalent inverse semigroups have Morita equivalent universal groupoids in the sense of Paterson and hence strongly Morita equivalent universal and reduced C*-algebras. As a consequence we obtain a new proof of a result of Khoshkam and Skandalis showing that the C*-algebra of an F-inverse semigroup is strongly Morita equivalent to a cross product of a commutative C*-algebra by a group.