Computing lebesgue number for an open covering

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The discussion centers on the Lebesgue number lemma, which states that for a compact metric space X and an open covering A, there exists a δ>0 such that any subset of X with diameter less than δ is contained in some element of A. The proof provided by Munkres allows for the computation of δ using a finite subcollection of A, though this δ may not be the smallest possible Lebesgue number. Participants express interest in whether there is a proof that identifies the smallest Lebesgue number, if it exists. Clarification is made regarding the terminology, specifically distinguishing between the largest and smallest Lebesgue numbers. The conversation indicates a desire to explore further the properties of Lebesgue numbers in open coverings.
Useful nucleus
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Munkres proof for the Lebesgue number lemma which is
(If X is a compact metric space and A is an open covering then there exists δ>0 such that for each subset of X having diameter less than δ , then there exists an element of the covering A containing it)
gives a way to compute δ using a finite subcollection that covers the compact metric space. However, this is not necessarily the smallest Lebesgue number. I wonder if there is another proof that involves evaluating the smallest Lebesgue number, if the latter exists.
 
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Useful nucleus, do you mean the largest Lebesgue number? Any positive number smaller than a Lebesgue number for a covering is also a Lebesgue number for the covering.
 
lugita15, you are absolutely right, I meant largest Lebesgue number if exist. I did not have time to refelct on this question again, but will give it a try soon.
 

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