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The contingent epiderivative and the calculus of variations on time scales. (English) Zbl 1239.49025
Summary: The calculus of variations on time scales is considered. We propose a new approach to the subject that consists of applying a differentiation tool called the contingent epiderivative. It is shown that the contingent epiderivative applied to the calculus of variations on time scales is very useful: it allows to unify the delta and nabla approaches previously considered in the literature. Generalized versions of the Euler-Lagrange necessary optimality conditions are obtained, both for the basic problem of the calculus of variations and isoperimetric problems. As particular cases one gets the recent delta and nabla results.
49K05Free problems in one independent variable (optimality conditions)
26E70Real analysis on time scales or measure chains
34N05Dynamic equations on time scales or measure chains