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arXiv · 2603.03516

Convex and quasiconvex truncations of nonconvex functions

Cornel Pintea
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Abstract

We consider nonconvex real valued functions whose truncations are either quasiconvex or even convex starting with a certain level. Among them, the $C^2$-smooth functions whose level sets are all completely contained in the positive definite region of their Hessian matrices, starting with a certain level, are good examples of such functions. For such a function we show the injectivity of its restricted gradient to a large subset of the positive definite region of its Hessian matrices.

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Cornel Pintea. 2026-03-03. Convex and quasiconvex truncations of nonconvex functions. https://arxiv.org/abs/2603.03516

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