Lemmas | Theorems in topology

Lebesgue's number lemma

In topology, Lebesgue's number lemma, named after Henri Lebesgue, is a useful tool in the study of compact metric spaces. It states: If the metric space is compact and an open cover of is given, then there exists a number such that every subset of having diameter less than is contained in some member of the cover. Such a number is called a Lebesgue number of this cover. The notion of a Lebesgue number itself is useful in other applications as well. (Wikipedia).

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From playlist Theory of numbers

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From playlist Abstract Algebra

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From playlist Real Analysis

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From playlist Measure Theory

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From playlist ℕumber Theory

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From playlist Real Analysis

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From playlist Measure Theory

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From playlist Real Analysis

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From playlist Measure Theory

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From playlist Math Problems with Number 2023

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From playlist Measure Theory

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From playlist École d’été 2013 - Théorie des nombres et dynamique

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Vaughn Climenhaga: Closed geodesics and the measure of maximal entropy on surfaces without...

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From playlist Jean-Morlet Chair - Pollicott/Vaienti

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From playlist Oxford Mathematics 1st Year Student Lectures

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From playlist Measure Theory

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From playlist Measure Theory

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From playlist Measure Theory

Related pages

Compact space | Metric space | Extreme value theorem | Topology | Henri Lebesgue | Subset | Diameter