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arXiv · 2107.07638

Quasi Differential Quotients

Francesca Angrisani·Franco Rampazzo
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Abstract

We explore basic properties and some applications of Quasi Differential Quotients ($QDQ$s) and the related $QDQ$-approximating multi-cones. A $QDQ$, which is a special kind of H.Sussmann's Approximate Generalized Differential Quotient ($AGDQ$), consists in a notion of generalized differentiation for set-valued maps. $QDQ$s have the advantage over $AGDQ$s of allowing a genuine, non-punctured, Open Mapping result, so implying stronger set-separation theorems. They have already proved quite useful in the investigation of some connections occurring between infimum gap phenomena and the normality of minima. Moreover, $QDQ$-approximating multi-cones are fit in optimal control to deduce Maximum Principles that involve (set-valued) Lie brackets of nonsmooth vector fields.

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Francesca Angrisani, Franco Rampazzo. 2021-07-15. Quasi Differential Quotients. https://arxiv.org/abs/2107.07638

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