Nonsmooth calculus

Heinonen, Juha

doi:10.1090/S0273-0979-07-01140-8

Nonsmooth calculus

Author: Juha Heinonen
Journal: Bull. Amer. Math. Soc. 44 (2007), 163-232
MSC (2000): Primary 28A75, 49J52, 53C23, 51-02
DOI: https://doi.org/10.1090/S0273-0979-07-01140-8
Published electronically: January 24, 2007
MathSciNet review: 2291675
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Abstract: We survey recent advances in analysis and geometry, where first order differential analysis has been extended beyond its classical smooth settings. Such studies have applications to geometric rigidity questions, but are also of intrinsic interest. The transition from smooth spaces to singular spaces where calculus is possible parallels the classical development from smooth functions to functions with weak or generalized derivatives. Moreover, there is a new way of looking at the classical geometric theory of Sobolev functions that is useful in more general contexts.

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