{"title":"Nonlinear Dynamics of a Roller Bicycle","authors":"Ivan A. Bizyaev, Ivan S. Mamaev","doi":"10.1134/S1560354724530017","DOIUrl":"10.1134/S1560354724530017","url":null,"abstract":"<div><p>In this paper we consider the dynamics of a roller\u0000bicycle on a horizontal plane. For this bicycle we derive a\u0000nonlinear system of equations of motion in a form that allows\u0000us to take into account the symmetry of the system in a\u0000natural form. We analyze in detail the stability of straight-line\u0000motion depending on the parameters of the bicycle.\u0000We find numerical evidence that, in addition to stable straight-line motion,\u0000the roller bicycle can exhibit other, more complex,\u0000trajectories for which the bicycle does not fall.</p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 5","pages":"728 - 750"},"PeriodicalIF":0.8,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933186","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":"(C^{1})-Smooth (Omega)-Stable Skew Products and Completely Geometrically Integrable Self-Maps of 3D-Tori, I: (Omega)-Stability","authors":"Lyudmila S. Efremova","doi":"10.1134/S1560354724520010","DOIUrl":"10.1134/S1560354724520010","url":null,"abstract":"<div><p>We prove here the criterion of <span>(C^{1})</span>- <span>(Omega)</span>-stability of self-maps of a 3D-torus, which\u0000are skew products of circle maps. The <span>(C^{1})</span>- <span>(Omega)</span>-stability property is studied with respect to homeomorphisms of skew products type. We give here an example of the <span>(Omega)</span>-stable map on a 3D-torus and investigate approximating properties of maps under consideration.</p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 3","pages":"491 - 514"},"PeriodicalIF":0.8,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933436","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":"Solvable Algebras and Integrable Systems","authors":"Valery V. Kozlov","doi":"10.1134/S1560354724520022","DOIUrl":"10.1134/S1560354724520022","url":null,"abstract":"<div><p>This paper discusses a range of questions concerning the application of\u0000solvable Lie algebras of vector fields to exact integration of systems of ordinary\u0000differential equations. The set of <span>(n)</span> independent vector fields\u0000generating a solvable Lie algebra in <span>(n)</span>-dimensional space is locally\u0000reduced to some “canonical” form. This reduction is performed constructively (using\u0000quadratures), which, in particular, allows a simultaneous integration of <span>(n)</span> systems of\u0000differential equations that are generated by these fields.\u0000Generalized completely integrable systems are introduced and their properties are investigated.\u0000General ideas are applied to integration of the Hamiltonian systems of differential equations.</p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 5","pages":"717 - 727"},"PeriodicalIF":0.8,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140942573","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":"Genericity of Homeomorphisms with Full Mean Hausdorff Dimension","authors":"Jeovanny Muentes Acevedo","doi":"10.1134/S1560354724510014","DOIUrl":"10.1134/S1560354724510014","url":null,"abstract":"<div><p>It is well known that the presence of horseshoes leads to positive entropy. If our goal is to construct a continuous map with infinite entropy, we can consider an infinite sequence of horseshoes, ensuring an unbounded number of legs.</p><p>Estimating the exact values of both the metric mean dimension and mean Hausdorff dimension for a homeomorphism is a challenging task. We need to establish a precise relationship between the sizes of the horseshoes and the number of appropriated legs to control both quantities.</p><p>Let <span>(N)</span> be an <span>(n)</span>-dimensional compact Riemannian manifold, where <span>(ngeqslant 2)</span>, and <span>(alphain[0,n])</span>. In this paper, we construct a homeomorphism <span>(phi:Nrightarrow N)</span> with mean Hausdorff dimension equal to <span>(alpha)</span>. Furthermore, we prove that the set of homeomorphisms on <span>(N)</span> with both lower and upper mean Hausdorff dimensions equal to <span>(alpha)</span> is dense in <span>(text{Hom}(N))</span>. Additionally, we establish that the set of homeomorphisms with upper mean Hausdorff dimension equal to <span>(n)</span> contains a residual subset of <span>(text{Hom}(N).)</span></p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 3","pages":"474 - 490"},"PeriodicalIF":0.8,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140629052","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":"Integrable Mechanical Billiards in Higher-Dimensional Space Forms","authors":"Airi Takeuchi, Lei Zhao","doi":"10.1134/S1560354724510038","DOIUrl":"10.1134/S1560354724510038","url":null,"abstract":"<div><p>In this article, we consider mechanical billiard systems defined with Lagrange’s integrable extension of Euler’s two-center problems in the Euclidean space, the sphere, and the hyperbolic space of arbitrary dimension <span>(ngeqslant 3)</span>. In the three-dimensional Euclidean space, we show that the billiard systems with any finite combinations of spheroids and circular hyperboloids of two sheets having two foci at the Kepler centers are integrable.\u0000The same holds for the projections of these systems on the three-dimensional sphere and\u0000in the three-dimensional hyperbolic space by means of central projection. Using the same approach, we also extend these results to the <span>(n)</span>-dimensional cases.</p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 3","pages":"405 - 434"},"PeriodicalIF":0.8,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140629055","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":"Numerical Evidence of Hyperbolic Dynamics and Coding of Solutions for Duffing-Type Equations with Periodic Coefficients","authors":"Mikhail E. Lebedev, Georgy L. Alfimov","doi":"10.1134/S156035472451004X","DOIUrl":"10.1134/S156035472451004X","url":null,"abstract":"<div><p>In this paper, we consider the equation <span>(u_{xx}+Q(x)u+P(x)u^{3}=0)</span> where <span>(Q(x))</span> and <span>(P(x))</span> are periodic\u0000functions. It is known that, if <span>(P(x))</span> changes sign, a “great part” of the solutions for this\u0000equation are singular, i. e., they tend to infinity at a finite point of the real axis. Our aim is to describe as completely as possible solutions, which are regular (i. e., not singular) on <span>(mathbb{R})</span>. For this purpose we consider the Poincaré map <span>(mathcal{P})</span> (i. e., the map-over-period) for this equation and analyse the areas of the plane <span>((u,u_{x}))</span> where <span>(mathcal{P})</span> and <span>(mathcal{P}^{-1})</span> are defined. We give sufficient conditions for hyperbolic dynamics generated by <span>(mathcal{P})</span> in these areas and show that the regular solutions correspond to a Cantor set situated in these areas. We also present a numerical algorithm for verifying these sufficient conditions at the level of “numerical evidence”. This allows us to describe regular solutions of this equation, completely or within some class, by means of symbolic dynamics. We show that regular solutions can be coded by bi-infinite sequences of symbols of some alphabet, completely or within some class. Examples of the application of this technique are given.</p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 3","pages":"451 - 473"},"PeriodicalIF":0.8,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140628477","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":"Biasymptotically Quasi-Periodic Solutions for Time-Dependent Hamiltonians","authors":"Donato Scarcella","doi":"10.1134/S1560354724510026","DOIUrl":"10.1134/S1560354724510026","url":null,"abstract":"<div><p>We consider time-dependent perturbations of integrable and near-integrable Hamiltonians. Assuming the perturbation decays polynomially fast as time tends to infinity, we prove the existence of biasymptotically quasi-periodic solutions. That is, orbits converging to some quasi-periodic solutions in the future (as <span>(tto+infty)</span>) and the past (as <span>(tto-infty)</span>).</p><p>Concerning the proof, thanks to the implicit function theorem, we prove the existence of a family of orbits converging to some quasi-periodic solutions in the future and another family of motions converging to some quasi-periodic solutions in the past. Then, we look at the intersection between these two families\u0000when <span>(t=0)</span>. Under suitable hypotheses on the Hamiltonian’s regularity and the perturbation’s smallness, it is a large set, and each point gives rise to biasymptotically quasi-periodic solutions.</p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 and Dmitry Treschev)","pages":"620 - 653"},"PeriodicalIF":0.8,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140629019","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}
Dijs de Neeling, Diederik Roest, Marcello Seri, Holger Waalkens
{"title":"Extremal Black Holes as Relativistic Systems with Kepler Dynamics","authors":"Dijs de Neeling, Diederik Roest, Marcello Seri, Holger Waalkens","doi":"10.1134/S1560354724020035","DOIUrl":"10.1134/S1560354724020035","url":null,"abstract":"<div><p>The recent detection of gravitational waves emanating from inspiralling black hole binaries has triggered a renewed interest in the dynamics of relativistic two-body systems. The conservative part of the latter are given by Hamiltonian systems obtained from so-called post-Newtonian expansions of the general relativistic description of black hole binaries. In this paper we study the general question of whether there exist relativistic binaries that display Kepler-like dynamics with elliptical orbits. We show that an orbital equivalence to the Kepler problem indeed exists for relativistic systems with a Hamiltonian of a Kepler-like form. This form is realised by extremal black holes with electric charge and scalar hair to at least first order in the post-Newtonian expansion for arbitrary mass ratios and to all orders in the post-Newtonian expansion in the test-mass limit of the binary. Moreover, to fifth post-Newtonian order, we show that Hamiltonians of the Kepler-like form can be related explicitly through a canonical transformation and time reparametrisation to the Kepler problem, and that all Hamiltonians conserving a Laplace – Runge – Lenz-like vector are related in this way to Kepler.</p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 2","pages":"344 - 368"},"PeriodicalIF":0.8,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140579014","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}
Clodoaldo Grotta-Ragazzo, Björn Gustafsson, Jair Koiller
{"title":"On the Interplay Between Vortices and Harmonic Flows: Hodge Decomposition of Euler’s Equations in 2d","authors":"Clodoaldo Grotta-Ragazzo, Björn Gustafsson, Jair Koiller","doi":"10.1134/S1560354724020011","DOIUrl":"10.1134/S1560354724020011","url":null,"abstract":"<div><p>Let <span>(Sigma)</span> be a compact manifold without boundary whose first homology is nontrivial. The Hodge decomposition of the incompressible Euler equation in terms of 1-forms yields a coupled PDE-ODE system. The <span>(L^{2})</span>-orthogonal components are a “pure” vorticity flow and a potential flow (harmonic, with the dimension of the homology). In this paper we focus on <span>(N)</span> point vortices on a compact Riemann surface without boundary of genus <span>(g)</span>, with a metric chosen in the conformal class. The phase space has finite dimension <span>(2N+2g)</span>. We compute a surface of section for the motion of a single vortex (<span>(N=1)</span>) on a torus (<span>(g=1)</span>) with a nonflat metric that shows typical features of nonintegrable 2 degrees of freedom Hamiltonians. In contradistinction, for flat tori the harmonic part is constant. Next, we turn to hyperbolic surfaces (<span>(ggeqslant 2)</span>) having constant curvature <span>(-1)</span>, with discrete symmetries. Fixed points of involutions yield vortex crystals in the Poincaré disk. Finally, we consider multiply connected planar domains. The image method due to Green and Thomson is\u0000viewed in the Schottky double. The Kirchhoff – Routh Hamiltonian\u0000given in C. C. Lin’s celebrated theorem is recovered by\u0000Marsden – Weinstein reduction from <span>(2N+2g)</span> to <span>(2N)</span>.\u0000The relation between the electrostatic Green function and the\u0000hydrodynamic Green function is clarified.\u0000A number of questions are suggested.</p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 2","pages":"241 - 303"},"PeriodicalIF":0.8,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140579141","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 Eisenhart’s Type Theorem for Sub-Riemannian Metrics on Step (2) Distributions with (mathrm{ad})-Surjective Tanaka Symbols","authors":"Zaifeng Lin, Igor Zelenko","doi":"10.1134/S1560354724020023","DOIUrl":"10.1134/S1560354724020023","url":null,"abstract":"<div><p>The classical result of Eisenhart states that, if a Riemannian metric <span>(g)</span> admits a Riemannian metric that is not constantly proportional to <span>(g)</span> and has the same (parameterized) geodesics as <span>(g)</span> in a neighborhood of a given point, then <span>(g)</span> is a direct product of two Riemannian metrics in this neighborhood. We introduce a new generic class of step <span>(2)</span> graded nilpotent Lie algebras, called <span>(mathrm{ad})</span><i>-surjective</i>, and extend the Eisenhart theorem to sub-Riemannian metrics on step <span>(2)</span> distributions with <span>(mathrm{ad})</span>-surjective Tanaka symbols. The class of ad-surjective step <span>(2)</span> nilpotent Lie algebras contains a well-known class of algebras of H-type as a very particular case.</p></div>","PeriodicalId":752,"journal":{"name":"Regular and Chaotic Dynamics","volume":"29 2","pages":"304 - 343"},"PeriodicalIF":0.8,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140579412","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}