The Cartesian product theorem for dimension 0

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SUMMARY

The Cartesian product theorem states that the Cartesian product ∏X = Xi of a countable family {Xi} of regular spaces is zero-dimensional if and only if all spaces Xi are zero-dimensional. The discussion raises questions about the necessity of the countability assumption for ensuring the regularity of the product space and its implications for the clopen basis. It is confirmed that products of an arbitrary number of regular spaces remain regular, indicating that the countability condition may not be essential for the proof. The proof provided appears to hold for uncountable products as well.

PREREQUISITES
  • Understanding of zero-dimensional spaces in topology
  • Familiarity with regular spaces and their properties
  • Knowledge of Cartesian products in topology
  • Basic comprehension of clopen sets and their significance
NEXT STEPS
  • Study the properties of zero-dimensional spaces in topology
  • Explore the concept of regular spaces and their implications
  • Investigate the role of countability in topological proofs
  • Review advanced topology texts that cover Cartesian products and their properties
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Mathematicians, topologists, and students studying advanced topology concepts, particularly those interested in the properties of regular and zero-dimensional spaces.

hedipaldi
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The cartesian product ∏X = Xi of a countable family {Xi} of regular spaces is zero-dimensional
i f and only i f all spaces Xi , are zero-dimensional.
I wonder if the countability assumption is just to ensure the regularity of the product space ,or it is crucial for the clopen basis.
Thank's
 
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Products of an arbitrary number of regular spaces are always regular, so the problem isn't there. Did you check the proof?? Where did they use countable?
What book is this anyway?
 
The proof seems to hold for uncountable product.The proof is attached.
 

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