{"title":"Nonlinear Fourier Transforms for the Sawada–Kotera Equation on the Line","authors":"Lin Huang, Deng-Shan Wang, Xiaodong Zhu","doi":"10.1111/sapm.70075","DOIUrl":null,"url":null,"abstract":"<div>\n \n <p>This paper presents a Riemann–Hilbert (RH) problem formalism for the initial value problem of the Sawada–Kotera equation defined on the real line. Assuming the existence of a solution, we establish that this solution can be effectively represented by solving a <span></span><math>\n <semantics>\n <mrow>\n <mn>3</mn>\n <mo>×</mo>\n <mn>3</mn>\n </mrow>\n <annotation>$3 \\times 3$</annotation>\n </semantics></math> matrix RH problem. Notably, the formulation of this RH problem involves four spectral functions: <span></span><math>\n <semantics>\n <msub>\n <mi>s</mi>\n <mn>32</mn>\n </msub>\n <annotation>$s_{32}$</annotation>\n </semantics></math>, <span></span><math>\n <semantics>\n <msub>\n <mi>s</mi>\n <mn>33</mn>\n </msub>\n <annotation>$s_{33}$</annotation>\n </semantics></math>, <span></span><math>\n <semantics>\n <msubsup>\n <mi>s</mi>\n <mn>32</mn>\n <mi>A</mi>\n </msubsup>\n <annotation>$s^A_{32}$</annotation>\n </semantics></math>, and <span></span><math>\n <semantics>\n <msubsup>\n <mi>s</mi>\n <mn>33</mn>\n <mi>A</mi>\n </msubsup>\n <annotation>$s^A_{33}$</annotation>\n </semantics></math>, which are obtained via a nonlinear Fourier transform applied to the initial data. Furthermore, this study conducts a detailed spectral analysis, providing a foundation for the application of the nonlinear steepest descent method to determine the long-time asymptotic behavior of solutions to the Sawada–Kotera equation on the real line.</p></div>","PeriodicalId":51174,"journal":{"name":"Studies in Applied Mathematics","volume":"155 1","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Studies in Applied Mathematics","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/sapm.70075","RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS, APPLIED","Score":null,"Total":0}
引用次数: 0
Abstract
This paper presents a Riemann–Hilbert (RH) problem formalism for the initial value problem of the Sawada–Kotera equation defined on the real line. Assuming the existence of a solution, we establish that this solution can be effectively represented by solving a matrix RH problem. Notably, the formulation of this RH problem involves four spectral functions: , , , and , which are obtained via a nonlinear Fourier transform applied to the initial data. Furthermore, this study conducts a detailed spectral analysis, providing a foundation for the application of the nonlinear steepest descent method to determine the long-time asymptotic behavior of solutions to the Sawada–Kotera equation on the real line.
期刊介绍:
Studies in Applied Mathematics explores the interplay between mathematics and the applied disciplines. It publishes papers that advance the understanding of physical processes, or develop new mathematical techniques applicable to physical and real-world problems. Its main themes include (but are not limited to) nonlinear phenomena, mathematical modeling, integrable systems, asymptotic analysis, inverse problems, numerical analysis, dynamical systems, scientific computing and applications to areas such as fluid mechanics, mathematical biology, and optics.