The Kolmogorov–riesz Compactness Theorem

نویسندگان

  • H. HANCHE-OLSEN
  • Helge Kristian Jenssen
چکیده

We show that the Arzelà–Ascoli theorem and Kolmogorov compactness theorem both are consequences of a simple lemma on compactness in metric spaces. Their relation to Helly’s theorem is discussed. The paper contains a detailed discussion on the historical background of the Kolmogorov compactness theorem.

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تاریخ انتشار 2009