In
mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
, in the field of
general topology, a
topological space is said to be mesocompact if every
open cover has a ''compact-finite'' open
refinement. That is, given any open cover, we can find an open refinement with the property that every compact set meets only finitely many members of the refinement.
[Pearl, p23]
The following facts are true about mesocompactness:
* Every
compact space, and more generally every
paracompact space is mesocompact. This follows from the fact that any
locally finite cover is automatically compact-finite.
* Every mesocompact space is
metacompact, and hence also
orthocompact. This follows from the fact that points are compact, and hence any compact-finite cover is automatically point finite.
Notes
References
*
* {{Citation, editor-first=Elliott, editor-last=Pearl, title=Open Problems in Topology II, year=2007, isbn=0-444-52208-5, publisher=Elsevier
Compactness (mathematics)
Properties of topological spaces