{"title":"Some remarks on Shanks-type conjectures","authors":"Christopher Felder","doi":"10.1007/s13324-024-00951-w","DOIUrl":"10.1007/s13324-024-00951-w","url":null,"abstract":"<div><p>We discuss the zero sets of two-variable polynomials as they relate to an approximation problem in the Hardy space on the bidisk.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vladislav V. Kravchenko, Víctor A. Vicente-Benítez
{"title":"Schrödinger equation with finitely many (delta )-interactions: closed form, integral and series representations for solutions","authors":"Vladislav V. Kravchenko, Víctor A. Vicente-Benítez","doi":"10.1007/s13324-024-00957-4","DOIUrl":"10.1007/s13324-024-00957-4","url":null,"abstract":"<div><p>A closed form solution for the one-dimensional Schrödinger equation with a finite number of <span>(delta )</span>-interactions </p><div><div><span>$$begin{aligned} {textbf{L}}_{q,{mathfrak {I}}_{N}}y:=-y^{prime prime }+left( q(x)+sum _{k=1}^{N}alpha _{k}delta (x-x_{k})right) y=lambda y,quad 0<x<b,;lambda in {mathbb {C}} end{aligned}$$</span></div></div><p>is presented in terms of the solution of the unperturbed equation </p><div><div><span>$$begin{aligned} {textbf{L}}_{q}y:=-y^{prime prime }+q(x)y=lambda y,quad 0<x<b,;lambda in {mathbb {C}} end{aligned}$$</span></div></div><p>and a corresponding transmutation (transformation) operator <span>({textbf{T}}_{{mathfrak {I}}_{N}}^{f})</span> is obtained in the form of a Volterra integral operator. With the aid of the spectral parameter power series method, a practical construction of the image of the transmutation operator on a dense set is presented, and it is proved that the operator <span>({textbf{T}}_{{mathfrak {I}}_{N}}^{f})</span> transmutes the second derivative into the Schrödinger operator <span>({textbf{L}}_{q,{mathfrak {I}}_{N}})</span> on a Sobolev space <span>(H^{2})</span>. A Fourier-Legendre series representation for the integral transmutation kernel is developed, from which a new representation for the solutions and their derivatives, in the form of a Neumann series of Bessel functions, is derived.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On the existence of radially symmetric solutions to p-k-Hessian equations and systems","authors":"Ling Mi, YangYang Ji","doi":"10.1007/s13324-024-00953-8","DOIUrl":"10.1007/s13324-024-00953-8","url":null,"abstract":"<div><p>The main objective of this paper is to study the <i>p</i>-<i>k</i>-Hessian problems. To our knowledge, the problems that has additional term in the <i>p</i>-<i>k</i>-Hessian operator were seldom studied in the literature. By means of monotone iteration method and Arzelà-Ascoli theorem, this paper investigates the existence of positive radially symmetric solutions of the following augmented <i>p</i>-<i>k</i>-Hessian equations </p><div><div><span>$$begin{aligned} S_{k} (lambda (D_{i}(|Du|^{p-2}D_{j}u) + alpha I)) =a^{k}(x)f^{k}(u),~xin mathbb {R}^n, end{aligned}$$</span></div></div><p>and <i>p</i>-<i>k</i>-Hessian systems </p><div><div><span>$$begin{aligned} {left{ begin{array}{ll} S_{k}(lambda (D_{i}(|Du|^{p-2}D_{j}u) + alpha I)) =a^{k}(x)f^{k}(v),~xin mathbb {R}^n, S_{k}(lambda (D_{i}(|Dv|^{p-2}D_{j}v) + alpha I)) = b^{k}(x)g^{k}(u),~xin mathbb {R}^n. end{array}right. } end{aligned}$$</span></div><div>\u0000 (0.1)\u0000 </div></div></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141880459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ill-posedness for the Camassa–Holm equation in (B_{p,1}^{1}cap C^{0,1})","authors":"Jinlu Li, Yanghai Yu, Yingying Guo, Weipeng Zhu","doi":"10.1007/s13324-024-00956-5","DOIUrl":"10.1007/s13324-024-00956-5","url":null,"abstract":"<div><p>In this paper, we study the Cauchy problem for the Camassa–Holm equation on the real line. By presenting a new construction of initial data, we show that the solution map in the smaller space <span>(B_{p,1}^{1}cap C^{0,1})</span> with <span>(pin (2,infty ])</span> is discontinuous at origin. More precisely, the initial data in <span>(B_{p,1}^{1}cap C^{0,1})</span> can guarantee that the Camassa–Holm equation has a unique local solution in <span>(W^{1,p}cap C^{0,1})</span>, however, this solution is instable and can have an inflation in <span>(B_{p,1}^{1}cap C^{0,1})</span>.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141880460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fractional maximal operators on weighted variable Lebesgue spaces over the spaces of homogeneous type","authors":"Xi Cen","doi":"10.1007/s13324-024-00955-6","DOIUrl":"10.1007/s13324-024-00955-6","url":null,"abstract":"<div><p>Let <span>((X,d,mu ))</span> is a space of homogeneous type, we establish a new class of fractional-type variable weights <span>(A_{p(cdot ), q(cdot )}(X))</span>. Then, we get the new weighted strong-type and weak-type characterizations for fractional maximal operators <span>(M_eta )</span> on weighted variable Lebesgue spaces over <span>((X,d,mu ))</span>. This study generalizes the results by Cruz-Uribe–Fiorenza–Neugebauer (J Math Anal Appl 64(394):744–760, 2012), Bernardis–Dalmasso–Pradolini (Ann Acad Sci Fenn-M 39:23-50, 2014), Cruz-Uribe–Shukla (Stud Math 242(2):109–139, 2018), and Cruz-Uribe–Cummings (Ann Fenn Math 47(1):457–488, 2022).</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141886741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Normalized solution to p-Kirchhoff-type equation in (mathbb {R}^{N})","authors":"ZhiMin Ren, YongYi Lan","doi":"10.1007/s13324-024-00954-7","DOIUrl":"10.1007/s13324-024-00954-7","url":null,"abstract":"<div><p>The paper is concerned with the <i>p</i>-Kirchhoff equation </p><div><div><span>$$begin{aligned} -left( a+bint _{mathbb {R}^{N}}|nabla u|^{p}dxright) Delta _{p} u=f(u)-mu u-V(x)u^{p-1}~~~~~in~~H^{1}(mathbb {R}^{N}), end{aligned}$$</span></div><div>\u0000 (1)\u0000 </div></div><p>where <span>(a,b>0)</span>. When <span>(V(x)=0)</span>, <span>(p=2)</span> and <span>(Nge 3)</span>, we obtain that any energy ground state normalized solutions of (1) has constant sign and is radially symmetric monotone with respect to some point in <span>(mathbb {R}^{N})</span> by using some energy estimates. When <span>(V(x)not equiv 0, p>sqrt{3}+1, frac{2}{p-2}<ple N<2p)</span>, under an explicit smallness assumption on <i>V</i> with <span>(lim _{|x|rightarrow infty }V(x)=sup _{mathbb {R}^{N}}V(x))</span>, we prove the existence of energy ground state normalized solutions of (1).</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Regularity and continuity of higher order maximal commutators","authors":"Feng Liu, Yuan Ma","doi":"10.1007/s13324-024-00952-9","DOIUrl":"10.1007/s13324-024-00952-9","url":null,"abstract":"<div><p>Let <span>(kge 1)</span>, <span>(0le alpha <d)</span> and <span>(mathfrak {M}_{b,alpha }^k)</span> be the <i>k</i>-th order fractional maximal commutator. When <span>(alpha =0)</span>, we denote <span>(mathfrak {M}_{b,alpha }^k=mathfrak {M}_{b}^k)</span>. We show that <span>(mathfrak {M}_{b,alpha }^k)</span> is bounded from the first order Sobolev space <span>(W^{1,p_1}(mathbb {R}^d))</span> to <span>(W^{1,p}(mathbb {R}^d))</span> where <span>(1<p_1,p_2,p<infty )</span>, <span>(1/p=1/p_1+k/p_2-alpha /d)</span>. We also prove that if <span>(0<s<1)</span>, <span>(1<p_1,p_2,p,q<infty )</span> and <span>(1/p=1/p_1+k/p_2)</span>, then <span>(mathfrak {M}_b^k)</span> is bounded and continuous from the fractional Sobolev space <span>(W^{s,p_1}(mathbb {R}^d))</span> to <span>({W^{s,p}(mathbb {R}^d)})</span> if <span>(bin W^{s,p_2}(mathbb {R}^d))</span>, from the inhomogeneous Triebel–Lizorkin space <span>(F_s^{p_1,q}(mathbb {R}^d))</span> to <span>(F_s^{p,q}(mathbb {R}^d))</span> if <span>(bin F_s^{p_2,q} (mathbb {R}^d))</span> and from the inhomogeneous Besov space <span>(B_s^{p_1,q}(mathbb {R}^d))</span> to <span>(B_s^{p,q}(mathbb {R}^d))</span> if <span>(bin B_s^{p_2,q}(mathbb {R}^d))</span>. It should be pointed out that the main ingredients of proving the above results are some refined and complex difference estimates of higher order maximal commutators as well as some characterizations of the Sobolev spaces, Triebel–Lizorkin spaces and Besov spaces.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exponential polynomials as solutions of certain type binomial differential equations","authors":"Linkui Gao, Changjiang Song","doi":"10.1007/s13324-024-00949-4","DOIUrl":"10.1007/s13324-024-00949-4","url":null,"abstract":"<div><p>In this paper, we focus on investigating the entire solutions to one certain type of non-linear binomial differential equations with respect to several problems posed by Gundersen and Yang. We also illustrate the exponential polynomials solutions to this equation. Some examples are used to illustrate our results.\u0000</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Inverse parameter and shape problem for an isotropic scatterer with two conductivity coefficients","authors":"Rafael Ceja Ayala, Isaac Harris, Andreas Kleefeld","doi":"10.1007/s13324-024-00950-x","DOIUrl":"10.1007/s13324-024-00950-x","url":null,"abstract":"<div><p>In this paper, we consider the direct and inverse problem for isotropic scatterers with two conductive boundary conditions. First, we show the uniqueness for recovering the coefficients from the known far-field data at a fixed incident direction for multiple frequencies. Then, we address the inverse shape problem for recovering the scatterer for the measured far-field data at a fixed frequency. Furthermore, we examine the direct sampling method for recovering the scatterer by studying the factorization for the far-field operator. The direct sampling method is stable with respect to noisy data and valid in two dimensions for partial aperture data. The theoretical results are verified with numerical examples to analyze the performance by the direct sampling method.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gerardo Ariznabarreta, Manuel Mañas, Piergiulio Tempesta
{"title":"Sobolev orthogonal polynomials, Gauss–Borel factorization and perturbations","authors":"Gerardo Ariznabarreta, Manuel Mañas, Piergiulio Tempesta","doi":"10.1007/s13324-024-00883-5","DOIUrl":"10.1007/s13324-024-00883-5","url":null,"abstract":"<div><p>We present a comprehensive class of Sobolev bi-orthogonal polynomial sequences, which emerge from a moment matrix with an <i>LU</i> factorization. These sequences are associated with a measure matrix defining the Sobolev bilinear form. Additionally, we develop a theory of deformations for Sobolev bilinear forms, focusing on polynomial deformations of the measure matrix. Notably, we introduce the concepts of Christoffel–Sobolev and Geronimus–Sobolev transformations. The connection formulas between these newly introduced polynomial sequences and existing ones are explicitly determined.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13324-024-00883-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141823957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}