Easton's theorem

In set theory, Easton's theorem is a result on the possible cardinal numbers of powersets. (extending a result of Robert M. Solovay) showed via forcing that and, for , that are the only constraints on permissible values for 2κ when κ is a regular cardinal.

Easton's theorem

In set theory, Easton's theorem is a result on the possible cardinal numbers of powersets. (extending a result of Robert M. Solovay) showed via forcing that and, for , that are the only constraints on permissible values for 2κ when κ is a regular cardinal.