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

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In summary, the conversation discusses the concepts of continuum product, sequentially compact spaces, and compact spaces in the Tychonoff topology. It also mentions an exercise involving the I^I space and the issue of whether it is compact in a certain topology. The conversation highlights the difference between sequentially compact and compact spaces, as well as their relationship in metrizable spaces.
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xaos
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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.
 

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

1. What is arbitrary product compactness?

Arbitrary product compactness is a mathematical concept used to measure the size and structure of a set of products. It is a way to determine how tightly or loosely packed the products are within a given space.

2. How is arbitrary product compactness calculated?

The arbitrary product compactness can be calculated by dividing the total volume of the products by the volume of the smallest enclosing shape that can contain all the products. This ratio provides a numerical value that represents the compactness of the products.

3. What factors can affect the arbitrary product compactness?

The arbitrary product compactness can be influenced by various factors such as the size and shape of the products, the arrangement of the products within the space, and the type of packing material used. In addition, external forces such as vibration or pressure can also impact the compactness of the products.

4. Why is arbitrary product compactness important?

Arbitrary product compactness is important in various industries, including manufacturing, logistics, and packaging. It can help optimize the use of space, reduce shipping costs, and improve the efficiency of product storage and transportation. It is also a useful tool for quality control, as it can indicate any potential issues with the packing process.

5. Are there any limitations to using arbitrary product compactness?

While arbitrary product compactness is a useful measure, it does have some limitations. It does not take into account the weight or fragility of the products, and it may not accurately reflect the actual packing density in real-world scenarios. Additionally, different methods of calculating compactness may yield different results. Therefore, it should be used in conjunction with other measures and considerations when assessing product packing.

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