Title of article :
is not closed
Author/Authors :
Zelenyuk، نويسنده , , Yevhen Zelenyuk، نويسنده ,
Issue Information :
دوماهنامه با شماره پیاپی سال 2011
Abstract :
Let S be an infinite discrete semigroup which can be embedded algebraically into a group and let βS be the Stone–Čech compactification of S. We show that if | S | is not Ulam-measurable, then the smallest ideal of βS is not closed.
Keywords :
Stone–?ech compactification , Ultrafilter semigroup , Smallest ideal , Idempotent , Extremally disconnected space
Journal title :
Topology and its Applications
Journal title :
Topology and its Applications
