Local Minimizers Of Semi-Algebraic Functions From The Viewpoint Of Tangencies

Consider a semialgebraic function $f\colon\mathbb{R}^n \to {\mathbb{R}},$ which is continuous around a point $\bar{x} \in \mathbb{R}^n.$ Using the so-called tangency variety of $f$ at $\bar{x},$ we first provide necessary and sufficient conditions for $\bar{x}$ to be a local minimizer of $f,$ and th...

Mô tả đầy đủ

Đã lưu trong:
Chi tiết về thư mục
Tác giả chính: Phạm, Tiến Sơn
Định dạng: Journal article
Ngôn ngữ:English
Được phát hành: Society for Industrial and Applied Mathematics 2021
Những chủ đề:
Truy cập trực tuyến:http://scholar.dlu.edu.vn/handle/123456789/500
Các nhãn: Thêm thẻ
Không có thẻ, Là người đầu tiên thẻ bản ghi này!
Thư viện lưu trữ: Thư viện Trường Đại học Đà Lạt
id oai:scholar.dlu.edu.vn:123456789-500
record_format dspace
spelling oai:scholar.dlu.edu.vn:123456789-5002022-02-10T22:56:32Z Local Minimizers Of Semi-Algebraic Functions From The Viewpoint Of Tangencies Phạm, Tiến Sơn Local minimizers Lojasiewicz gradient inequality Optimality conditions Semialgebraic Sharp minimality Strong metric subregularity Tangencies Consider a semialgebraic function $f\colon\mathbb{R}^n \to {\mathbb{R}},$ which is continuous around a point $\bar{x} \in \mathbb{R}^n.$ Using the so-called tangency variety of $f$ at $\bar{x},$ we first provide necessary and sufficient conditions for $\bar{x}$ to be a local minimizer of $f,$ and then in the case where $\bar{x}$ is an isolated local minimizer of $f,$ we define a “tangency exponent” $\alpha_* > 0$ so that for any $\alpha \in \mathbb{R}$ the following four conditions are always equivalent: (i) the inequality $\alpha \ge \alpha_*$ holds, (ii) the point $\bar{x}$ is an $\alpha$th order sharp local minimizer of $f$, (iii) the limiting subdifferential $\partial f$ of $f$ is $(\alpha - 1)$th order strongly metrically subregular at $\bar{x}$ for 0, and (iv) the function $f$ satisfies the Łojaseiwcz gradient inequality at $\bar{x}$ with the exponent $1 - \frac{1}{\alpha}.$ Besides, we also present a counterexample to a conjecture posed by Drusvyatskiy and Ioffe [Math. Program. Ser. A, 153 (2015), pp. 635--653]. 30 3 1777–1794 2021-08-23T08:09:07Z 2021-08-23T08:09:07Z 2020-07 Journal article Bài báo đăng trên tạp chí thuộc ISI, bao gồm book chapter http://scholar.dlu.edu.vn/handle/123456789/500 10.1137/19M1237466 en ISSN (print): 1052-6234 ISSN (online): 1095-7189 Society for Industrial and Applied Mathematics
institution Thư viện Trường Đại học Đà Lạt
collection Thư viện số
language English
topic Local minimizers
Lojasiewicz gradient inequality
Optimality conditions
Semialgebraic
Sharp minimality
Strong metric subregularity
Tangencies
spellingShingle Local minimizers
Lojasiewicz gradient inequality
Optimality conditions
Semialgebraic
Sharp minimality
Strong metric subregularity
Tangencies
Phạm, Tiến Sơn
Local Minimizers Of Semi-Algebraic Functions From The Viewpoint Of Tangencies
description Consider a semialgebraic function $f\colon\mathbb{R}^n \to {\mathbb{R}},$ which is continuous around a point $\bar{x} \in \mathbb{R}^n.$ Using the so-called tangency variety of $f$ at $\bar{x},$ we first provide necessary and sufficient conditions for $\bar{x}$ to be a local minimizer of $f,$ and then in the case where $\bar{x}$ is an isolated local minimizer of $f,$ we define a “tangency exponent” $\alpha_* > 0$ so that for any $\alpha \in \mathbb{R}$ the following four conditions are always equivalent: (i) the inequality $\alpha \ge \alpha_*$ holds, (ii) the point $\bar{x}$ is an $\alpha$th order sharp local minimizer of $f$, (iii) the limiting subdifferential $\partial f$ of $f$ is $(\alpha - 1)$th order strongly metrically subregular at $\bar{x}$ for 0, and (iv) the function $f$ satisfies the Łojaseiwcz gradient inequality at $\bar{x}$ with the exponent $1 - \frac{1}{\alpha}.$ Besides, we also present a counterexample to a conjecture posed by Drusvyatskiy and Ioffe [Math. Program. Ser. A, 153 (2015), pp. 635--653].
format Journal article
author Phạm, Tiến Sơn
author_facet Phạm, Tiến Sơn
author_sort Phạm, Tiến Sơn
title Local Minimizers Of Semi-Algebraic Functions From The Viewpoint Of Tangencies
title_short Local Minimizers Of Semi-Algebraic Functions From The Viewpoint Of Tangencies
title_full Local Minimizers Of Semi-Algebraic Functions From The Viewpoint Of Tangencies
title_fullStr Local Minimizers Of Semi-Algebraic Functions From The Viewpoint Of Tangencies
title_full_unstemmed Local Minimizers Of Semi-Algebraic Functions From The Viewpoint Of Tangencies
title_sort local minimizers of semi-algebraic functions from the viewpoint of tangencies
publisher Society for Industrial and Applied Mathematics
publishDate 2021
url http://scholar.dlu.edu.vn/handle/123456789/500
_version_ 1768305772153798656