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Katok’s Entropy Formula of Unstable Metric Entropy for Partially Hyperbolic Diffeomorphisms
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作者 Ping Huang Chenwei Wang Ercai Chen 《Communications in Mathematics and Statistics》 SCIE CSCD 2024年第2期339-355,共17页
Katok’s entropy formula is an important formula in entropy theory.It plays significant roles in large deviation theories,multifractal analysis,quantitative recurrence and so on.This paper is devoted to establishing K... Katok’s entropy formula is an important formula in entropy theory.It plays significant roles in large deviation theories,multifractal analysis,quantitative recurrence and so on.This paper is devoted to establishing Katok’s entropy formula of unstable metric entropy which is the entropy caused by the unstable part of partially hyperbolic systems.We also construct a similar formula which can be used to study the quantitative recurrence in the unstable manifold for partially hyperbolic diffeomorphisms. 展开更多
关键词 Katok’s entropy formula Unstable metric entropy Measure decomposition Partially hyperbolic diffeomorphisms
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Discreteness of Flux Groups 被引量:1
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作者 Yong Seung CHO Myung Im LIM 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第1期115-122,共8页
Let (M, ω) be a closed symplectic 2n-dimensional manifold. Donaldson in his paper showed that there exist 2m-dimensional symplectie submanifolds (V^2m,ω) of (M,ω), 1 ≤m ≤ n - 1, with (m - 1)-equivalent in... Let (M, ω) be a closed symplectic 2n-dimensional manifold. Donaldson in his paper showed that there exist 2m-dimensional symplectie submanifolds (V^2m,ω) of (M,ω), 1 ≤m ≤ n - 1, with (m - 1)-equivalent inclusions. On the basis of this fact we obtain isomorphic relations between kernel of Lefschetz map of M and kernels of Lefschetz maps of Donaldson submanifolds V^2m, 2 ≤ m ≤ n - 1. Then, using this relation, we show that the flux group of M is discrete if the action of π1 (M) on π2(M) is trivial and there exists a retraction r : M→ V, where V is a 4-dimensional Donaldson submanifold. And, in the symplectically aspherical case, we investigate the flux groups of the manifolds. 展开更多
关键词 Symplectic diffeomorphisms FLUX Symplectically aspherical manifold Donaldson submanifold
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A MULTIDIMENSIONAL CENTRAL LIMIT THEOREM WITH SPEED OF CONVERGENCE FOR AXIOM A DIFFEOMORPHISMS
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作者 夏红强 檀大耀 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1123-1132,共10页
Let T:X → X be an Axiom A diffeomorphism,m the Gibbs state for a Hlder continuous function ɡ. Assume that f:X → R^d is a Hlder continuous function with ∫_X^(fdm) = 0.If the components of f are cohomologously i... Let T:X → X be an Axiom A diffeomorphism,m the Gibbs state for a Hlder continuous function ɡ. Assume that f:X → R^d is a Hlder continuous function with ∫_X^(fdm) = 0.If the components of f are cohomologously independent, then there exists a positive definite symmetric matrix σ~2:=σ~2 (f ) such that S^fn √ n converges in distribution with respect to m to a Gaussian random variable with expectation 0 and covariance matrix σ~2 . Moreover, there exists a real number A 〉 0 such that, for any integer n ≥ 1,Π( m*( 1√ nS f n ),N (0,σ~2 ) ≤A√n, where m*(1√ n S^fn)denotes the distribution of 1√ n S^fn with respect to m, and Π is the Prokhorov metric. 展开更多
关键词 multidimensional central limit theorem Axiom A diffeomorphisms symbolic dynamics transfer operator
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Scattering Cross-Sections in Quantum Gravity—The Case of Matter-Matter Scattering
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作者 Christian Wiesendanger 《Journal of Modern Physics》 2015年第3期273-282,共10页
Viewing gravitational energy-momentum PG<sup style='margin-left:-7px;'>μ as equal by observation, but different in essence from inertial energy-momentum PI<sup style='margin-left:-7px;'>μ... Viewing gravitational energy-momentum PG<sup style='margin-left:-7px;'>μ as equal by observation, but different in essence from inertial energy-momentum PI<sup style='margin-left:-7px;'>μ naturally leads to the gauge theory of volume-preserving diffeomorphisms of a four-dimensional inner space. To analyse scattering in this theory, the gauge field is coupled to two Dirac fields with different masses. Based on a generalized LSZ reduction formula the S-matrix element for scattering of two Dirac particles in the gravitational limit and the corresponding scattering cross-section are calculated to leading order in perturbation theory. Taking the non-relativistic limit for one of the initial particles in the rest frame of the other the Rutherford-like cross-section of a non-relativistic particle scattering off an infinitely heavy scatterer calculated quantum mechanically in Newtonian gravity is recovered. This provides a non-trivial test of the gauge field theory of volume-preserving diffeomorphisms as a quantum theory of gravity. 展开更多
关键词 Renormalizable QUANTUM GRAVITY SCATTERING CROSS-SECTIONS in QUANTUM GRAVITY Gauge Theory of Volume-Preserving diffeomorphisms
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EMBEDDING FLOWS OF DIFFEOMORPHISMS
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作者 Yangyou Pan Xiang Zhang 《Annals of Differential Equations》 2014年第2期166-173,共8页
In this paper we first survey the results on the embedding flow problem of dif-feomorphisms in higher dimensional spaces. Next we present some new results on the characterization of semi-unipotent diffeomorphisms in R... In this paper we first survey the results on the embedding flow problem of dif-feomorphisms in higher dimensional spaces. Next we present some new results on the characterization of semi-unipotent diffeomorphisms in R3, which have a formal embedding flows. 展开更多
关键词 diffeomorphisms embedding vector field normal form
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Conservation of Gravitational Energy Momentum and Renormalizable Quantum Theory of Gravitation
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作者 Christian Wiesendanger 《Journal of Modern Physics》 2013年第8期133-152,共20页
Viewing gravitational energy-momentum as equal by observation, but different in essence from inertial energymomentum naturally leads to the gauge theory of volume-preserving diffeomorphisms of an inner Minkowski space... Viewing gravitational energy-momentum as equal by observation, but different in essence from inertial energymomentum naturally leads to the gauge theory of volume-preserving diffeomorphisms of an inner Minkowski space which can describe gravitation at the classical level. This theory is quantized in the path integral formalism starting with a non-covariant Hamiltonian formulation with unconstrained canonical field variables and a manifestly positive Hamiltonian. The relevant path integral measure and weight are then brought into a Lorentz- and gauge-covariant form allowing to express correlation functions—applying the De Witt-Faddeev-Popov approach—in any meaningful gauge. Next the Feynman rules are developed and the quantum effective action at one loop in a background field approach is renormalized which results in an asymptotically free theory without presence of other fields and in a theory without asymptotic freedom including the Standard Model (SM) fields. Finally the BRST apparatus is developed as preparation for the renormalizability proof to all orders and a sketch of this proof is given. 展开更多
关键词 Path Integral QUANTIZATION GAUGE Theory Volume-Preserving diffeomorphisms
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Trivial and Simple Spectrum for SL(d,R) Cocycles with Free Base and Fiber Dynamics
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作者 Mrio BESSA Paulo VARANDAS 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2015年第7期1113-1122,共10页
Let ACD(M, SL(d,R)) denote the pairs (f, A) so that f∈ A C Diff^1(M) is a C^1-Anosov transitive diffeomorphisms and A is an SL(d,R) cocycle dominated with respect to f. We prove that open and densely in ACD... Let ACD(M, SL(d,R)) denote the pairs (f, A) so that f∈ A C Diff^1(M) is a C^1-Anosov transitive diffeomorphisms and A is an SL(d,R) cocycle dominated with respect to f. We prove that open and densely in ACD(M, SL(d,R)), in appropriate topologies, the pair (f,A) has simple spectrum with respect to the unique maximal entropy measure μf. Then, we prove prevalence of trivial spectrum near the dynamical cocycle of an area-preserving map and also for generic cocycles in AUtLeb(M) × LP(M, SL(d, R)). 展开更多
关键词 Linear cocycles Lyapunov exponents Anosov diffeomorphisms topological conjugacy maximal entropy measures
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Weighted area-minimizing submanifolds with soap-film-like singularities assembled from special Lagrangian pieces
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作者 HIEU Doan The 《Science China Mathematics》 SCIE 2010年第10期2749-2754,共6页
A suffcient condition for a set of calibrated submanifolds to be area-minimizing with multiplicities,also call weighted area-minimizing under diffeomorphisms (WAMD) is stated.We construct some WAMD submanifolds by ass... A suffcient condition for a set of calibrated submanifolds to be area-minimizing with multiplicities,also call weighted area-minimizing under diffeomorphisms (WAMD) is stated.We construct some WAMD submanifolds by assembling pieces of special Lagrangian (SL) normal bundles including the one of three surfaces meeting at an angle of 120° along soap-film-like singularities.We also mention a symmetry property of SL submanifolds and Bjrling type problem for SL normal bundles. 展开更多
关键词 WEIGHTED area-minimizing under diffeomorphisms SPECIAL LAGRANGIAN
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Quasisymmetric property for conjugacies between Anosov diffeomorphisms of the two-torus
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作者 HU HuYi 1 & JIANG YunPing 2, 1 Department of Mathematics, Michigan State University, East Lansing, MI 48824, USA 2 Department of Mathematics, the Graduate Center and Queens College of CUNY, Flushing, NY 11367, USA 《Science China Mathematics》 SCIE 2010年第3期663-670,共8页
We prove that the restrictions of the conjugacy between two Anosov diffeomorphisms of the twotorus to the stable and unstable manifolds are quasisymmetric homeomorphisms.
关键词 quasisymmetry Anosov diffeomorphisms CONJUGACY Hlder condition MARKOV PARTITION
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Twistor quantization of the space of half-differentiable vector functions on the circle revisited
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作者 SERGEEV Armen 《Science China Mathematics》 SCIE 2009年第12期2714-2729,共16页
We discuss the twistor quantization problem for the classical system (V d ,A d ), represented by the phase space V d , identified with the Sobolev space H 0 1/2 (S 1,? d ) of half-differentiable vector functions on th... We discuss the twistor quantization problem for the classical system (V d ,A d ), represented by the phase space V d , identified with the Sobolev space H 0 1/2 (S 1,? d ) of half-differentiable vector functions on the circle, and the algebra of observables A d , identified with the semi-direct product of the Heisenberg algebra of V d and the algebra Vect(S 1) of tangent vector fields on the circle. 展开更多
关键词 twistor quantization Sobolev space of half-differentiable functions group of diffeomorphisms of the circle 58E20 53C28 32L25
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A Renormalizable Theory of Quantum Gravity: Renormalization Proof of the Gauge Theory of Volume Preserving Diffeomorphisms
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作者 Christian Wiesendanger 《Journal of Modern Physics》 2014年第10期959-983,共25页
Inertial and gravitational mass or energy momentum need not be the same for virtual quantum states. Separating their roles naturally leads to the gauge theory of volume-preserving diffeomorphisms of an inner four-dime... Inertial and gravitational mass or energy momentum need not be the same for virtual quantum states. Separating their roles naturally leads to the gauge theory of volume-preserving diffeomorphisms of an inner four-dimensional space. The gauge-fixed action and the path integral measure occurring in the generating functional for the quantum Green functions of the theory are shown to obey a BRST-type symmetry. The related Zinn-Justin-type equation restricting the corresponding quantum effective action is established. This equation limits the infinite parts of the quantum effective action to have the same form as the gauge-fixed Lagrangian of the theory proving its spacetime renormalizability. The inner space integrals occurring in the quantum effective action which are divergent due to the gauge group’s infinite volume are shown to be regularizable in a way consistent with the symmetries of the theory demonstrating as a byproduct that viable quantum gauge field theories are not limited to finite-dimensional compact gauge groups as is commonly assumed. 展开更多
关键词 RENORMALIZATION PROOF of GAUGE Field THEORY of Volume-Preserving diffeomorphisms
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Centralizers and Iterate Radicals of Morse-Smale Diffeomorphisms of the Circle
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作者 Zhang Meirong Department of Applied Mathematics Tsinghua University Beijing,100084 China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1995年第1期1-11,共11页
In this paper,we will use the embedding flows in[1],[2]to give a complete descrip- tion of the smooth centralizers and iterate radicals of all C^r(r≥2)Morse-Smale diffeomorphisms of the circle S^1.As a result,we prov... In this paper,we will use the embedding flows in[1],[2]to give a complete descrip- tion of the smooth centralizers and iterate radicals of all C^r(r≥2)Morse-Smale diffeomorphisms of the circle S^1.As a result,we prove that every centralizer is a solvable subgroup of Diff^r(S^1). 展开更多
关键词 Centralizers and Iterate Radicals of Morse-Smale diffeomorphisms of the Circle TDFs
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微分同胚的不可积性
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作者 王冰杰 许志国 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2008年第6期1113-1115,共3页
考虑微分同胚的不可积性.在非共振情形下给出了解析微分同胚存在形式首次积分的必要条件,进而在一般共振情形下给出了解析微分同胚存在形式首次积分的必要条件.
关键词 微分同胚 首次积分 不可积性 共振
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利用吸引盆证明Hardamard-Levy定理
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作者 潘庆茂 王文相 《连云港师范高等专科学校学报》 2004年第4期77-78,共2页
在局部同胚的条件下,Hardamard-Levy定理给出数值连续法可行性的条件。文章利用吸引盆为工具,推广 了在Banach空间判定全局同胚的条件,并以此为基础,给出了Hardamard-Levy定理的一种新的证明。
关键词 吸引盆 全局同胚 连续法 延拓性
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基于流体映射模型的医学图像弹性配准 被引量:2
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作者 何力 周康源 +2 位作者 李长富 胡耀辉 陈增胜 《北京生物医学工程》 2005年第5期366-369,378,共5页
为了实现约束条件下的非刚性匹配,引入流体映射模型,以两组反映待配准图像轮廓信息的对应控制点集,对头颅,肝,脾等各种器官进行弹形匹配。流体模型借用了流体运动中流体的相互关系的数学模型,通过寻求控制点集的最优变换轨迹,以实现图... 为了实现约束条件下的非刚性匹配,引入流体映射模型,以两组反映待配准图像轮廓信息的对应控制点集,对头颅,肝,脾等各种器官进行弹形匹配。流体模型借用了流体运动中流体的相互关系的数学模型,通过寻求控制点集的最优变换轨迹,以实现图像各象素点相互制约的平滑变形。实验结果证明,无论是对小变形还是大变形图像的弹性配准,使用流体映射模型都能取得良好的配准效果。 展开更多
关键词 弹性配准 流体映射模型 控制点 拉格朗日变换轨迹
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关于低维Sobolev同胚的两个问题 献给余家荣教授100华诞
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作者 叶东 《中国科学:数学》 CSCD 北大核心 2019年第11期1707-1720,共14页
本文讨论和介绍Sobolev同胚的一些性质及相关结果,证明一维情形下微分同胚在Sobolev同胚中的稠密性,还证明在固定体积形式和边界的约束下,如果二维圆盘上新的体积形式是径向对称的并且一致靠近于Lebesgue测度,那么旋转对称同胚是Dirich... 本文讨论和介绍Sobolev同胚的一些性质及相关结果,证明一维情形下微分同胚在Sobolev同胚中的稠密性,还证明在固定体积形式和边界的约束下,如果二维圆盘上新的体积形式是径向对称的并且一致靠近于Lebesgue测度,那么旋转对称同胚是Dirichlet能量的唯一极小解. 展开更多
关键词 Sobolev同胚 微分同胚的稠密性 体积形式约束下的Dirichlet能量
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关于显式的Alekseev-Meinrenken微分同胚
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作者 肖哲衡 王嘉晟 《数学进展》 CSCD 北大核心 2020年第5期561-572,共12页
Alekseev-Meinrenken微分同胚是一个从埃尔米特矩阵集合到正定埃尔米特矩阵集合的映射,该映射由某些特殊的线性代数性质唯一刻画.本文运用纯线性代数方法重新给出了该微分同构的具体公式.
关键词 埃尔米特矩阵 Gelfand-Zeitlin系统 Alekseev-Meinrenken微分同胚
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三相有源电力滤波器精确反馈线性化空间矢量PWM复合控制 被引量:33
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作者 乐江源 谢运祥 +1 位作者 张志 陈林 《中国电机工程学报》 EI CSCD 北大核心 2010年第15期32-39,共8页
提出一种基于精确反馈线性化的三相有源电力滤波器空间矢量脉宽调制控制方法。在三相并联型有源电力滤波器的仿射非线性模型基础上,推导出其状态反馈精确线性化非线性控制律,实现三相并联型有源电力滤波器有功补偿电流和无功补偿电流的... 提出一种基于精确反馈线性化的三相有源电力滤波器空间矢量脉宽调制控制方法。在三相并联型有源电力滤波器的仿射非线性模型基础上,推导出其状态反馈精确线性化非线性控制律,实现三相并联型有源电力滤波器有功补偿电流和无功补偿电流的解耦控制。选取适当的反馈系数可确定交流侧指令电压,利用空间矢量脉宽调制技术对所需的指令电压进行逼近。与PI控制的三角载波控制方案进行仿真对比分析,验证了所提出的控制方案的动、静性能指标均优于PI控制方案。研制了一台小功率样机,验证了所提方案的正确性和可行性。 展开更多
关键词 有源电力滤波器 解耦控制 精确反馈线性化 空间矢量脉宽调制 微分同胚
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欠驱动水面船舶的曲线航迹跟踪控制 被引量:12
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作者 曾薄文 朱齐丹 于瑞亭 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2011年第10期1317-1322,共6页
针对欠驱动水面船舶的航迹跟踪控制面临着本质非线性、强耦合和无法线性化处理的控制等问题,首先通过对欠驱动水面船舶航迹控制系统的非线性模型.进行全局微分同胚和反馈变换,构造了由2个级联的子系统构成的航迹跟踪误差系统,然后基于... 针对欠驱动水面船舶的航迹跟踪控制面临着本质非线性、强耦合和无法线性化处理的控制等问题,首先通过对欠驱动水面船舶航迹控制系统的非线性模型.进行全局微分同胚和反馈变换,构造了由2个级联的子系统构成的航迹跟踪误差系统,然后基于反步法的设计原理,运用Lyapunov直接方法对变换后的误差系统设计了航迹跟踪控制律,该控制律可以实现一定条件下欠驱动水面船舶的曲线航迹跟踪.仿真结果验证了该控制律的有效性. 展开更多
关键词 欠驱动水面船舶 跟踪控制 反步法 微分同胚
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非线性经济时间序列的相空间重构及预测 被引量:5
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作者 王庆余 《天津职业技术师范学院学报》 2003年第1期23-26,共4页
综述了通过一维的经济时间序列的相空间重构技术构造反映产生经济时间序列的原始系统的本质因素的理论,并举例说明了该技术的实际应用。
关键词 非线性经济时间序列 相空间重构 预测 混沌吸引子 微分同胚 李雅普诺夫指数 计量经济学 股票市场
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