A chain rule involving vector functions of bounded variation
Moreau, Jean Jacques ; Valadier, Michel
HAL, hal-01788917 / Harvested from HAL
By f ϵ lbv(I, X), we mean that f is a function of a real interval I to a Banach space X, with bounded variation on every compact subinterval of I; to such f, an X-valued measure df, called its differential measure, classically corresponds. Let Ω be an open convex subset of X and γ: Ω → . Two situations are investigated where the function γ ∘ f: t → γ (f(t)) belongs to lbv(I) and some properties of the real measure d(γ ∘ f) are established. In the first case, γ is supposed convex and continuous in Ω. The subdifferential δγ is invoked in the sense of Convex Analysis; under the ordering of real measures, d(γ ∘ f) is shown to satisfy some inequalities. This generalizes previous results of one of the authors, aimed at deriving energy-like inequalities in nonsmooth mechanical evolution problems. In the second case, γ is supposed Lipschitz on every bounded subset of Ω and Clarke's generalized gradient of γ is used. In both situations, if γ happens to be Gâteaux-differentiable, and f ϵ lbv(I, X) continuous, a chain rule of the familiar form is found to hold. Finally, for γ Fréchet-differentiable, an expression of d(γ ∘ f) is obtained.
Publié le : 1987-10-04
Classification:  [MATH]Mathematics [math],  [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]
@article{hal-01788917,
     author = {Moreau, Jean Jacques and Valadier, Michel},
     title = {A chain rule involving vector functions of bounded variation},
     journal = {HAL},
     volume = {1987},
     number = {0},
     year = {1987},
     language = {en},
     url = {http://dml.mathdoc.fr/item/hal-01788917}
}
Moreau, Jean Jacques; Valadier, Michel. A chain rule involving vector functions of bounded variation. HAL, Tome 1987 (1987) no. 0, . http://gdmltest.u-ga.fr/item/hal-01788917/