Topological property of the Cantor set

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The discussion centers on proving that a separable, zero-dimensional metric space X is homeomorphic to a subset of the Cantor set. The approach involves using a collection of functions that separate points from closed sets, leading to the evaluation map being an embedding. It is noted that X has a countable basis of clopen sets, which aids in constructing functions mapping X to {0,1}. Concerns are raised about the injectivity of the resulting function into the product space, with a suggestion that the Hausdorff property of X ensures injectivity. The conversation emphasizes the importance of these properties in establishing the homeomorphism.
hedipaldi
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Let X be a metric separable metric and zero dimensional space.Then X is homeomorphic to a subset of Cantor set.
How can it be proved?
Thank's a lot,
Hedi
 
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Hint: prove the following theorem:

  • Let ##X## be a ##T_1## space (= singletons are closed). Let ##\{f_i~\vert~i\in I\}## be a collection of functions ##f_i:X\rightarrow X_i## which separates points from closed sets, then the evaluation map ##e:X\rightarrow \prod_{i\in I}X_i## is an embedding.

Now, your space ##X## has a countable basis consisting of clopen sets (why?). Use this to construct functions ##f_n:X\rightarrow \{0,1\}## for ##n\in \mathbb{N}## and apply the theorem.
 
Thank you.
 
Injectivity of the function

The resulting function from X into the product space doesn't seem to be one-to-one.Maybe i fail to see something?
 
After further thinking i suppose injectivity is due to X being Haussdorff.Am i right?
 

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