Vocab Flashcards
Compact
Every open cover has a finite subcover
Closed
Contains all its own limit points, complement is open
Complement
Overarching set minus A
Topology
Subset of the power set, finite intersections, arbitrary unions, contains the entire set and the null.
Limit point
Any neighborhood of a limit point of A contains a different point of A
Open set
Any set that’s in the topology
Continuous
Open sets in destination have open preimages in source
Connected
Can’t be represented as union of disjoint open sets.
Path Connected
There’s an f: [0,1] to A with f(0) = a, f(1) = b, for any a,b in A.
Locally Path Connected
Every neighborhood has a path connected subset.
Locally Connected
Every neighborhood has a connected subset.
Cover
Set of open sets whose union contains the covered set
Subcover
Subset of the index of a cover, which still contains the covered set.