Sobolev Algebras Through a ‘Carré Du Champ’ Identity

  title={Sobolev Algebras Through a ‘Carr{\'e} Du Champ’ Identity},
  author={Fr{\'e}d{\'e}ric Bernicot and Dorothee Frey},
  journal={Proceedings of the Edinburgh Mathematical Society},
  pages={1041 - 1054}
  • F. Bernicot, D. Frey
  • Published 1 December 2016
  • Mathematics
  • Proceedings of the Edinburgh Mathematical Society
Abstract We consider abstract Sobolev spaces of Bessel-type associated with an operator. In this work, we pursue the study of algebra properties of such functional spaces through the corresponding semigroup. As a follow-up to our previous work, we show that by making use of the property of a ‘carré du champ’ identity, this algebra property holds in a wider range than previously shown. 
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