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Transcript
uniformizable space∗
CWoo†
2013-03-21 22:16:33
Let X be a topological space with T the topology defined on it. X is said
to be uniformizable
1. there is a uniformity U defined on X, and
2. T = TU , the uniform topology induced by U.
It can be shown that a topological space is uniformizable iff it is completely
regular.
Clearly, every pseudometric space is uniformizable. The converse is true if
the space has a countable basis. Pushing this idea further, one can show that
a uniformizable space is metrizable iff it is separating (or Hausdorff) and has a
countable basis.
Let X, T , and U be defined as above. Then X is said to be completely
uniformizable if U is a complete uniformity.
Every paracompact space is completely uniformizable. Every completely
uniformizable space is completely regular, and hence uniformizable.
∗ hUniformizableSpacei created: h2013-03-21i by: hCWooi version: h39055i Privacy
setting: h1i hDefinitioni h54E15i
† This text is available under the Creative Commons Attribution/Share-Alike License 3.0.
You can reuse this document or portions thereof only if you do so under terms that are
compatible with the CC-BY-SA license.
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