A surprising formula for Sobolev norms

Haïm Brezis1,2,3,4, Jean Van Schaftingen5, Po-Lam Yung6,7

  • 1Department of Mathematics, Rutgers University, Piscataway, NJ 08854; brezis@math.rutgers.edu.

Summary

This study demonstrates a key equivalence in Sobolev and Gagliardo seminorms, replacing strong derivatives with weak ones. This finding offers new estimation methods for fractional inequalities in specific mathematical cases.

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