Let the space $\mathbb{R}^n$ be endowed with a Minkowski structure $M$ (that is $M\colon \mathbb{R}^n \to [0,+\infty)$ is the gauge function of a compact convex set having the origin as an interior point, and with boundary of class $C^2$), and let $d^M(x,y)$ be the (asymmetric) distance associated to $M$. Given an open domain $Ω\subset\mathbb{R}^n$ of class $C^2$, let $d_Ω(x) := \inf\{d^M(x,y); y\in\partialΩ\}$ be the Minkowski distance of a point $x\inΩ$ from the boundary of $Ω$. We prove that a suitable extension of $d_Ω$ to $\mathbb{R}^n$ (which plays the röle of a signed Minkowski distance to $\partial Ω$) is of class $C^2$ in a tubular neighborhood of $\partial Ω$, and that $d_Ω$ is of class $C^2$ outside the cut locus of $\partialΩ$ (that is the closure of the set of points of non--differentiability of $d_Ω$ in $Ω$). In addition, we prove that the cut locus of $\partial Ω$ has Lebesgue measure zero, and that $Ω$ can be decomposed, up to this set of vanishing measure, into geodesics starting from $\partialΩ$ and going into $Ω$ along the normal direction (with respect to the Minkowski distance). We compute explicitly the Jacobian determinant of the change of variables that associates to every point $x\in Ω$ outside the cut locus the pair $(p(x), d_Ω(x))$, where $p(x)$ denotes the (unique) projection of $x$ on $\partialΩ$, and we apply these techniques to the analysis of PDEs of Monge-Kantorovich type arising from problems in optimal transportation theory and shape optimization.
Alfréd Rényi Institute of Mathematics, Hungarian Academy of Sciences(匈牙利科学院阿尔弗雷德·雷尼数学研究所);Lagrange Mathematical and Computational Center(拉格朗日数学与计算中心);Instituto Nacional de Matemática Pura e Aplicada(纯粹与应用数学国家研究所)
研究Minkowski体及其L_p-Minkowski体在1 ≤ p ≠ n范围内的定量稳定性,证明了概率测度的Hausdorff距离和Fraenkel不对称性与测度距离之间的关系。
Key Laboratory of Pure and Applied Mathematics, School of Mathematical Sciences, Peking University(北京大学数学科学学院纯与应用数学重点实验室);Mathematisches Institut, Albert-Ludwigs-Universität Freiburg(弗莱堡大学数学研究所);Centro di Ricerca Matematica Ennio De Giorgi, Scuola Normale Superiore(比萨高等师范学院恩尼奥·德乔治数学研究中心);Dipartimento di Matematica, Università di Pisa(比萨大学数学系)