compact Hausdorff space is extremally disconnected if its function algebra is a bounded complete lattice
Let be a compact Hausdorff space and the algebra of continuous functions
. Recall that is a vector lattice with the usual order (http://planetmath.org/PartialOrder): takes positive
(or zero) values.
Theorem - If every subset of that is bounded from above has a least upper bound (i.e. is a bounded complete lattice), then is extremally disconnected.