{"title":"Periodic Solutions for a Class of Nonlinear Differential Equations","authors":"Huafeng Xiao, Juan Xiao, Jianshe Yu","doi":"10.1007/s10884-024-10375-6","DOIUrl":"https://doi.org/10.1007/s10884-024-10375-6","url":null,"abstract":"<p>In this paper, we address the existence and multiplicity of 2-periodic solutions to differential equations with a distributed delay of the form </p><span>$$begin{aligned} x^{prime }(t)=fBig [int _{t-1}^t gbig (x(s)big ) d sBig ],quad x in textbf{R}^N. end{aligned}$$</span><p>Combining Kaplan–Yorke’s method with pseudoindex theory, we estimate the number of periodic solutions when the equations are both resonant and nonresonant. More specifically, we define two indices using asymptotic linear coefficient matrices at the origin and at infinity. Then the lower bound on the number of periodic solutions to the equations is estimated by the indices. Finally, two examples are given to illustrate our results.</p>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"44 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Krzysztof Leśniak, Nina Snigireva, Filip Strobin, Andrew Vince
{"title":"Highly Non-contractive Iterated Function Systems on Euclidean Space Can Have an Attractor","authors":"Krzysztof Leśniak, Nina Snigireva, Filip Strobin, Andrew Vince","doi":"10.1007/s10884-024-10367-6","DOIUrl":"https://doi.org/10.1007/s10884-024-10367-6","url":null,"abstract":"<p>Iterated function systems (IFSs) and their attractors have been central to the theory of fractal geometry almost from its inception. Moreover, contractivity of the functions in the IFS has been central to the theory of iterated functions systems. If the functions in the IFS are contractions, then the IFS is guaranteed to have a unique attractor. The converse question, does the existence of an attractor imply that the IFS is contractive, originates in a 1959 work by Bessaga which proves a converse to the contraction mapping theorem. Although a converse is true in that case, it is known that it does not always hold for an IFS. In general, there do exist IFSs with attractors and which are not contractive. However, in the context of IFSs in Euclidean space, this question has been open. In this paper we show that a highly non-contractive iterated function system in Euclidean space can have an attractor. In order to do that, we introduce the concept of an <i>L</i>-expansive map, i.e., a map that has Lipschitz constant strictly greater than one under any remetrization. This is necessitated by the absence of positively expansive maps on the interval.\u0000</p>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"23 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Semiflows Strongly Focusing Monotone with Respect to High-Rank Cones: I. Generic Dynamics","authors":"Lirui Feng","doi":"10.1007/s10884-024-10372-9","DOIUrl":"https://doi.org/10.1007/s10884-024-10372-9","url":null,"abstract":"<p>We consider a smooth semiflow strongly focusing monotone with respect to a cone of rank <i>k</i> on a Banach space. We obtain its generic dynamics, that is, semiorbits with initial data from an open and dense subset of any open bounded set either are pseudo-ordered or convergent to an equilibrium. For the case <span>(k=1)</span>, it is the celebrated Hirsch’s Generic Convergence Theorem. For the case <span>(k=2)</span>, we obtain the generic Poincaré-Bendixson Theorem.</p>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"46 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141502919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nonlocal Balance Equation: Representation and Approximation of Solution","authors":"Yurii Averboukh","doi":"10.1007/s10884-024-10373-8","DOIUrl":"https://doi.org/10.1007/s10884-024-10373-8","url":null,"abstract":"<p>We study a nonlocal balance equation that describes the evolution of a system consisting of infinitely many identical particles those move along a deterministic dynamics and can also either disappear or give a spring. In this case, the solution of the balance equation is considered in the space of nonnegative measures. We prove the superposition principle for the examined nonlocal balance equation. Furthermore, we interpret the source/sink term as a probability rate of jumps from/to a remote point. Using this idea and replacing the deterministic dynamics of each particle by a nonlinear Markov chain, we approximate the solution of the balance equation by a solution of a system of ODEs and evaluate the corresponding approximation rate. This result can be used for construction of numerical solutions of the nonlocal balance equation.</p>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"26 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141551852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exponential Mixing for Heterochaos Baker Maps and the Dyck System","authors":"Hiroki Takahasi","doi":"10.1007/s10884-024-10370-x","DOIUrl":"https://doi.org/10.1007/s10884-024-10370-x","url":null,"abstract":"<p>We investigate mixing properties of piecewise affine non-Markovian maps acting on <span>([0,1]^2)</span> or <span>([0,1]^3)</span> and preserving the Lebesgue measure, which are natural generalizations of the <i>heterochaos baker maps</i> introduced in Saiki et al. (Nonlinearity 34:5744–5761, 2021). These maps are skew products over uniformly expanding or hyperbolic bases, and the fiber direction is a center in which both contracting and expanding behaviors coexist. We prove that these maps are mixing of all orders. For maps with a mostly expanding or contracting center, we establish exponential mixing for Hölder functions. Using this result, for the Dyck system originating in the theory of formal languages, we establish exponential mixing for Hölder functions with respect to its two coexisting ergodic measures of maximal entropy.</p>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"41 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141253028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On the Well-Posedness of Two Driven-Damped Gross–Pitaevskii-Type Models for Exciton-Polariton Condensates","authors":"Jakob Möller, Jesus Sierra","doi":"10.1007/s10884-024-10359-6","DOIUrl":"https://doi.org/10.1007/s10884-024-10359-6","url":null,"abstract":"<p>We study the well-posedness of two systems modeling the non-equilibrium dynamics of pumped decaying Bose–Einstein condensates. In particular, we present the local theory for rough initial data using the Fourier restricted norm method introduced by Bourgain. We extend the result globally for initial data in <span>(L^{2})</span>.</p>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"47 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141060400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"First-time Sensitive Homeomorphisms","authors":"Mayara Antunes, Bernardo Carvalho","doi":"10.1007/s10884-024-10362-x","DOIUrl":"https://doi.org/10.1007/s10884-024-10362-x","url":null,"abstract":"<p>We introduce first-time sensitivity for a homeomorphism of a compact metric space, that is a condition on the first increasing times of open balls of the space. Continuum-wise expansive homeomorphisms, the shift map on the Hilbert cube, and also some partially hyperbolic diffeomorphisms satisfy this condition. We prove the existence of local unstable continua satisfying similar properties with the local unstable continua of continuum-wise expansive homeomorphisms, but assuming first-time sensitivity. As a consequence we prove that first-time sensitivity (with some additional technical assumptions) implies positive topological entropy.</p>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"85 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140601659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A KAM Theorem for the Time Quasi-periodic Reversible Perturbations of Linear Wave Equations Beyond Brjuno Conditions","authors":"","doi":"10.1007/s10884-024-10360-z","DOIUrl":"https://doi.org/10.1007/s10884-024-10360-z","url":null,"abstract":"<h3>Abstract</h3> <p>This paper is concerned with the existence of quasi-periodic response solutions (i.e., solutions that are quasi-periodic with the same frequencies as forcing term) for a class of forced reversible wave equations with derivative nonlinearity. The forcing frequency <span> <span>(omega in mathbb {R}^2)</span> </span> would be Liouvillean which is weaker than the usual Diophantine and Brjuno conditions. The derivative nonlinearity in the equation also leads to some difficulty in measure estimate. To overcome it, we also use the Töplitz–Lipschitz property of vector field. The proof is based on an infinite dimensional Kolmogorov–Arnold–Moser theorem for reversible systems.</p>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"22 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140601704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On the Structure of Entropy Solutions to the Riemann Problem for a Degenerate Nonlinear Parabolic Equation","authors":"","doi":"10.1007/s10884-024-10361-y","DOIUrl":"https://doi.org/10.1007/s10884-024-10361-y","url":null,"abstract":"<h3>Abstract</h3> <p>We find an explicit form of entropy solution to a Riemann problem for a degenerate nonlinear parabolic equation with piecewise constant velocity and diffusion coefficients. It is demonstrated that this solution corresponds to the minimum point of some strictly convex function of a finite number of variables. We also discuss the limit when piecewise constant coefficients approximate the arbitrary ones.</p>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"67 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140602199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Non-collision Orbits for a Class of Singular Hamiltonian Systems on the Plane with Weak Force Potentials","authors":"Mohamed Antabli, Morched Boughariou","doi":"10.1007/s10884-024-10363-w","DOIUrl":"https://doi.org/10.1007/s10884-024-10363-w","url":null,"abstract":"<p>We study the existence of non-collision orbits for a class of singular Hamiltonian systems </p><span>$$begin{aligned} ddot{q}+ V'(q)=0 end{aligned}$$</span><p>where <span>(q:{mathbb {R}} longrightarrow {mathbb {R}}^2)</span> and <span>(Vin C^2({mathbb {R}}^2 {setminus } {e},, {mathbb {R}}))</span> is a potential with a singularity at a point <span>(enot =0)</span>. We consider <i>V</i> which behaves like <span>(displaystyle -1/|q-e|^alpha )</span> as <span>( qrightarrow e )</span> with <span>(alpha in ]0,2[.)</span> Under the assumption that 0 is a strict global maximum for <i>V</i>, we establish the existence of a homoclinic orbit emanating from 0. Moreover, in case <span>(displaystyle V(q) longrightarrow 0)</span> as <span>(|q|rightarrow +infty )</span>, we prove the existence of a heteroclinic orbit “at infinity\" i.e. a solution <i>q</i> such that </p><span>$$begin{aligned} lim _{trightarrow -infty } q(t)=0,,, lim _{t rightarrow +infty }|q(t)|=+infty ,, hbox {and} , lim _{t rightarrow pm infty }dot{q}(t)=0. end{aligned}$$</span>","PeriodicalId":15624,"journal":{"name":"Journal of Dynamics and Differential Equations","volume":"35 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140602200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}