Is Every Arbitrary Product of Compact Spaces Compact in Any Topology?

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SUMMARY

The discussion centers on the properties of compact spaces and their products, specifically referencing the Tychonoff theorem, which states that an arbitrary product of compact spaces is compact in the Tychonoff topology. However, the conversation highlights that the product of sequentially compact spaces may not be sequentially compact, leading to confusion regarding the compactness of I^I in different topologies. The distinction between the product topology and the box topology is crucial, as the latter can lead to non-compactness despite the individual spaces being compact.

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  • Understanding of compact spaces and their properties
  • Familiarity with the Tychonoff theorem and its implications
  • Knowledge of product topology versus box topology
  • Concept of sequential compactness and its relationship to compactness
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  • Study the Tychonoff theorem in detail, focusing on its proof and applications
  • Explore the differences between product topology and box topology
  • Investigate the concept of sequential compactness in various topological spaces
  • Examine examples of non-compact spaces derived from compact products in different topologies
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Mathematicians, particularly those specializing in topology, students studying advanced concepts in topology, and anyone interested in the properties of compact spaces and their products.

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i'm reading Hocking&Young(Dover), and its clear I've missed something in my understanding.

first it mentions in sec1-8 that a continuum product of sequencially compact spaces (therefore compact?) need not be sequentially compact (therefore not compact?)

then it proves thm1-28 that an arbitrary product of compact spaces in the Tychonoff topology is compact, the so called 'Tychonoff theorem'

then in an exercise it asks you to show that I^I is not compact in some unmentioned topology. isn't this an arbitrary product of compact spaces?

perhaps these are all distinct ideas, but its unclear to me what that is. i know whether or not the space is a metric space is an issue, but how?
 
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Tychonoff does show that any product of compact spaces is compact (a "product" of spaces always implies the product topology, by the way). So the I^I example must be using a different topology, maybe box.

Also, compact spaces are sequentially compact and limit point compact, but in general the converse doesn't hold. It does hold in metrizable spaces, where the three notions are equivalent.
 

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