Hint
|
Answer
|
T1 and normal
|
t4
|
For all x ∈ X, for all open U ∋ x, there
exists connected C and open V such that x ∈ V ⊆ C ⊆ U
|
locally connected
|
For all x ∈ X and open U ∋ x, there exists open V and compact K such that x ∈ V ⊆ K ⊆ U
|
locally compact
|
There is continuous f : X → [0, 1] such that f(A) ⊆ {0} and f(B) ⊆ {1
|
functionally separated
|
T is the coarsest topology such that all πλ are continuous
|
tychonoff topology
|
Every open cover has a locally finite open refinement
|
paracompact
|
∀u ∈ U, ∃v ∈ V, u ⊆ v
|
refinement
|
For all x ∈ X, there exists open V ∋ x such that V ∩ U /= ∅ for only finitely many U ∈ U
|
locally finite
|
Whenever C and D are disjoint and closed in X,
there exist open U and V such that C ⊆ U, D ⊆ V , and U ∩ V = ∅
|
normal
|
Every countable open cover
has a finite subcover
|
countably compact
|
Whenever x and y are distinct points
of X, there is an open set U such that either x ∈ U and y /∈ U, or x /∈ U and y ∈ U
|
t0
|
For all A ⊆ X, either A ∈ U, or X \ A ∈ U
|
ultafilter
|
Whenever x ∈ X and C ⊆ X is closed, and x /∈ C,
there exist open U, V such that x ∈ U, C ⊆ V and U ∩ V = ∅
|
regular
|
|
Hint
|
Answer
|
f is closed, and has compact fibres
|
proper
|
Whenever C is a closed set, and x /∈ C, {x} and C are functionally separated
|
completely regular
|
The set of all F ⊆ X such that x ∈ F◦
|
neighbourhood filter
|
X has a countable basis
|
second countable
|
h : X → Y has the following properties:
a) h is one-to-one,
b) h is a homeomorphism from X to h(X),
c) h(X) is dense in Y
|
hausdorff compactification
|
T1 and regular
|
t3
|
1. ≤ is a total order of Y , and
2. Every non-empty subset of Y has a ≤-least element
|
well ordering
|
1. αX is a topological space with points X ∪ {∗}, such that U is open iff
a) U is open in X, or
b) ∗ ∈ U, and X \ U is compact.
2. h : X → X ∪ {∗} is the identity
|
alexandroff compatification
|
Completely regular and T1
|
tychonoff
|
Every open cover has a countable
subcover
|
lindelof
|
Whenever x /= y ∈ X, there exists open U,
V such that x ∈ U, y ∈ V and U ∩ V = ∅
|
t2
|
Whenever x and y are distinct points
of X, there is an open set U such that x ∈ U and y /∈ U
|
t1
|
Compact Hausdorff space with a basis of clopen
sets
|
stone space
|
|