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On the Inverse Limit of Higson Compactifications 被引量:1
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作者 曹阳 孙以丰 《Northeastern Mathematical Journal》 CSCD 2002年第2期95-98,共4页
Higson have introduced the conception of "Higson’s corona" (see [1]). For a given metric space X, it is a kind of compactification of X related to the metric d on it. Denote by BR(X) the set {y ∈ X\d(x,y) ... Higson have introduced the conception of "Higson’s corona" (see [1]). For a given metric space X, it is a kind of compactification of X related to the metric d on it. Denote by BR(X) the set {y ∈ X\d(x,y) < R}. Recall that a slowly oscillating function on X is a function f G C*(X) satisfying the following condition: 展开更多
关键词 stone-cech corapactification Higson compactification coarse equivalent
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Resolvable Spaces and Compactifications
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作者 Monerah Al-Hajri Karim Belaid 《Advances in Pure Mathematics》 2013年第3期365-367,共3页
This paper deals with spaces such that their compactification is a resolvable space. A characterization of space such that its one point compactification (resp. Wallman compactification) is a resolvable space is given.
关键词 RESOLVABLE SPACE Alexandroff compactification Wallman compactification
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A&zeta;x- and Open <i>C<sub>D</sub><sup>*</sup></i>-Filters Process of Compactifications and Any Hausdorff Compactification
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作者 Hueytzen J. Wu Wan-Hong Wu 《Advances in Pure Mathematics》 2012年第4期296-300,共5页
By means of a characterization of compact spaces in terms of open CD*-filters induced by a , a - and open CD*-filters process of compactifications of an arbitrary topological space Y is obtained in Sec. 3 by embedding... By means of a characterization of compact spaces in terms of open CD*-filters induced by a , a - and open CD*-filters process of compactifications of an arbitrary topological space Y is obtained in Sec. 3 by embedding Y as a dense subspace of , YS = {ε |ε is an open CD*-filter that does not converge in Y}, YT = {A|A is a basic open CD*-filter that does not converge in Y}, is the topology induced by the base B = {U*|U is open in Y, U ≠φ} and U* = {F∈Ysw (or YTw)|U∈F}. Furthermore, an arbitrary Hausdorff compactification (Z, h) of a Tychonoff space X?can be obtained from a by the?similar process in Sec.3. 展开更多
关键词 Net OPEN FILTER OPEN CD*-Filter Base Basic OPEN CD*-Filter OPEN CD*-Filter -Filter x-Filter Tychonoff Space Normal T1-Space Compact Space compactificationS stone-cech compactification Wallman compactification
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A Modified Wallman Method of Compactification
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作者 Hueytzen J.Wu Wan-Hong Wu 《Advances in Pure Mathematics》 2013年第6期590-597,共8页
Closed and basic closed C*D-filters are used in a process similar to Wallman method for compactifications of the topological spaces Y, of which, there is a subset of C*(Y) containing a non-constant function, where C*(... Closed and basic closed C*D-filters are used in a process similar to Wallman method for compactifications of the topological spaces Y, of which, there is a subset of C*(Y) containing a non-constant function, where C*(Y) is the set of bounded real continuous functions on Y. An arbitrary Hausdorff compactification (Z,h) of a Tychonoff space X can be obtained by using basic closed C*D-filters from in a similar way, where C(Z) is the set of real continuous functions on Z. 展开更多
关键词 Closed █_(x)-Filter Open and Closed C^(*)_(D)-Filter Bases Basic Open and Closed C^(*)_(D)-Filters compactification stone-cech and Wallman compactifications
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Proof That Spatial Transitions Release/Absorb Energy That Compactification Necessarily Leads to Changes in Volume, Energy and Entropy
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第2期310-320,共11页
Using simple box quantization, we demonstrate explicitly that a spatial transition will release or absorb energy, and that compactification releases latent heat with an attendant change in volume and entropy. Increasi... Using simple box quantization, we demonstrate explicitly that a spatial transition will release or absorb energy, and that compactification releases latent heat with an attendant change in volume and entropy. Increasing spatial dimension for a given number of particles costs energy while decreasing dimensions supplies energy, which can be quantified, using a generalized version of the Clausius-Clapyeron relation. We show this explicitly for massive particles trapped in a box. Compactification from N -dimensional space to (N - 1) spatial dimensions is also simply demonstrated and the correct limit to achieve a lower energy result is to take the limit, Lw → 0, where Lw is the compactification length parameter. Higher dimensional space has more energy and more entropy, all other things being equal, for a given cutoff in energy. 展开更多
关键词 SPATIAL TRANSITIONS Box Quantization compactification
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An Expository on Some Nonstandard Compactifications
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作者 Alagu Somasundaram Rukhmoni Kala 《Advances in Pure Mathematics》 2021年第10期807-815,共9页
Three classical compactification procedures are presented with nonstandard flavour. This is to illustrate the applicability of Nonstandard analytic tool to beginners interested in Nonstandard analytic methods. The gen... Three classical compactification procedures are presented with nonstandard flavour. This is to illustrate the applicability of Nonstandard analytic tool to beginners interested in Nonstandard analytic methods. The general procedure is as follows: A suitable equivalence relation is defined on an enlargement <sup>*</sup>X of the space X which is a completely regular space or a locally compact Hausdorff space or a locally compact Abelian group. Accordingly, every f in C(X,R) (the space of bounded continuous real valued functions on X) or Cc(X,R) (the space of continuous real valued functions on X with compact support) or the dual group <span style="white-space:nowrap;">&#915; of the locally compact Abelian group G is extended to the set <img alt="" src="Edit_b9535172-924d-44f0-bab3-c49db17a3b7a.png" /> of the above mentioned equivalence classes. A compact topology on <img alt="" src="Edit_9d7962a3-b8a3-4693-b62a-078c8c4b4853.png" /> is obtained as the weak topology generated by these extensions of f. Then X is naturally imbedded densely in <img alt="" src="Edit_f7d403b2-eff3-4555-b8e7-1b106e06d2e7.png" />. 展开更多
关键词 Non-Standard compactification Completely Regular Space Locally Compact Hausdorff Space Locally Compact Abelian Group
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QUOTIENT SPACE OF LMC-COMPACTIFICATION AS A SPACE OF z-FILTERS
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作者 Mohammad Akbari Tootkaboni 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期2010-2020,共11页
The left multiplicative continuous compactification is the universal semigroup compactification of a semitopological semigroup.In this paper an internal construction of a quotient space of the left multiplicative cont... The left multiplicative continuous compactification is the universal semigroup compactification of a semitopological semigroup.In this paper an internal construction of a quotient space of the left multiplicative continuous compactification of a semitopological semigroup is constructed as a space of z-filters 展开更多
关键词 LMC-compactification z-filters quotient space
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More Compactification for Differential Systems
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作者 Harry Gingold Daniel Solomon 《Advances in Pure Mathematics》 2013年第1期190-203,共14页
This article is a review and promotion of the study of solutions of differential equations in the “neighborhood of infinity” via a non traditional compactification. We define and compute critical points at infinity ... This article is a review and promotion of the study of solutions of differential equations in the “neighborhood of infinity” via a non traditional compactification. We define and compute critical points at infinity of polynomial autonomuos differential systems and develop an explicit formula for the leading asymptotic term of diverging solutions to critical points at infinity. Applications to problems of completeness and incompleteness (the existence and nonexistence respectively of global solutions) of dynamical systems are provided. In particular a quadratic competing species model and the Lorentz equations are being used as arenas where our technique is applied. The study is also relevant to the Painlevé property and to questions of integrability of dynamical systems. 展开更多
关键词 Nonlinear Polynomial compactification Ultra Extended Euclidean Space CRITICAL POINT Equilibrium POINT CRITICAL POINT at INFINITY CRITICAL Direction at INFINITY BASIN of Divergence BASIN of Convergence Ideal Solutions Asymptotic Stability Global Globally Asymptotically Stable Jacobian Painleve Analysis Competing Species Model Lorenz Equations Periodic Surface Differential Geometry Attractor REPELLER
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Extra Time Dimension: Deriving Relativistic Space-Time Transformations, Kinematics, and Example of Dimensional Compactification Using Time-Dependent Non-Relativistic Quantum Mechanics
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作者 Sajjad Zahir 《Journal of Modern Physics》 2023年第10期1333-1354,共22页
We consider a five-dimensional Minkowski space with two time dimensions characterized by distinct speeds of causality and three space dimensions. Formulas for relativistic coordinate and velocity transformations are d... We consider a five-dimensional Minkowski space with two time dimensions characterized by distinct speeds of causality and three space dimensions. Formulas for relativistic coordinate and velocity transformations are derived, leading to a new expression for the speed limit. Extending the ideas of Einstein’s Theory of Special Relativity, concepts of five-velocity and five-momenta are introduced. We get a new formula for the rest energy of a massive object. Based on a non-relativistic limit, a two-time dependent Schrödinger-like equation for infinite square-well potential is developed and solved. The extra time dimension is compactified on a closed loop topology with a period matching the Planck time. It generates interference of additional quantum states with an ultra-small period of oscillation. Some cosmological implications of the concept of four-dimensional versus five-dimensional masses are briefly discussed, too. 展开更多
关键词 Two-Time Physics Special Theory of Relativity Kaluza-Klein Theory Time-Dependent Schrödinger Equation compactification
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Effects of Compactification on Free Massive Scalar Fields in Five-Dimensional Space-Time with an Extra Time Dimension: Analysing Some Results
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作者 Sajjad Zahir 《Journal of Modern Physics》 2023年第12期1600-1616,共17页
This paper deals with some aspects of two-time physics (i.e., 2T + 3S five-dimensional space) for a Minkowski-like space with distinct speeds of causality for the time dimensions. Detailed calculations are provided to... This paper deals with some aspects of two-time physics (i.e., 2T + 3S five-dimensional space) for a Minkowski-like space with distinct speeds of causality for the time dimensions. Detailed calculations are provided to obtain results of Kaluza-Klein type compactification for free massive scalar fields and abelian free gauge fields. As already indicated in the literature, a tower of massive fields results from the compactification with mass terms having signs opposite to those of the ones appearing in other five-dimensional theories with an extra space dimension. We perform elaborate numerical calculations to highlight the magnitude of the imaginary masses and ask if we need to explore alternative compactification techniques. 展开更多
关键词 Two-Time Physics Theory of Special Relativity Kaluza-Klein Theory compactification Klein-Gordon Equation TACHYONS Abelian Gauge Theory
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A Inherent Characterization of L-fuzzy Compactification
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作者 孟培源 周武能 《湖北科技学院学报》 1994年第1期1-9,共9页
AInherentCharacterizationofL-fuzzyCompactification¥Mengpeiyuan(XianningTeachers'College,Hubei,China)Zhouwune... AInherentCharacterizationofL-fuzzyCompactification¥Mengpeiyuan(XianningTeachers'College,Hubei,China)Zhouwuneng(YunyangTeacher... 展开更多
关键词 α-ultra-closed filter Nice-compactness T_(1)-seperation L-fuzzy topological space compactification
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可定向复三维卡拉比-丘流形的计算与数据库构建
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作者 高鸿飞 高昕 《四川大学学报(自然科学版)》 北大核心 2025年第2期465-471,共7页
为了满足IIB型弦理论紧致化的需求,我们基于Kreuzer和Skarke构建的多面体数据库,计算并生成了一个可定向复三维卡拉比-丘流形数据库.计算流程如下:首先,通过四维自反多面体构建一个四维Toric底空间,并确定该底空间中存在的一般复三维卡... 为了满足IIB型弦理论紧致化的需求,我们基于Kreuzer和Skarke构建的多面体数据库,计算并生成了一个可定向复三维卡拉比-丘流形数据库.计算流程如下:首先,通过四维自反多面体构建一个四维Toric底空间,并确定该底空间中存在的一般复三维卡拉比-丘流形的超平面表达式.同时,通过分析除子的拓扑性质,确定底空间中可能存在的除子交换Z2对称性.进一步,我们计算了具有除子交换Z2对称性的复三维卡拉比-丘流形及其固定点等性质,并评估了其在IIB型弦理论紧致化中的适用性.在固定点计算过程中,我们对相关计算步骤进行了简化处理.统计结果表明,这种简化对固定点计算结果的影响小于1%,但显著减少了计算时间,从而大幅提高了计算效率.我们的研究不仅为IIB型弦理论紧致化提供了重要的数据支持,也展示了计算方法优化在复杂几何计算中的潜力. 展开更多
关键词 卡拉比-丘流形 弦紧致化 IIB型弦理论
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球面与紧致空间乘积的K理论
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作者 唐九奇 崔婷婷 钟佳媚 《红河学院学报》 2025年第2期132-133,140,共3页
在拓扑K理论中,我们主要证明了如下结果:对任意紧致的Hausdorff空间X,存在以下同构,当n=2k(k≥0)时,K^(0)(X×S~n)≌K^(0)(x)十K^(0)(X);而当n=2k-1(k≥1)时,有K^(0)(X×S~n)≌K^(-1)(X)■K^(0)(X).当n=2k-1(k≥1)时,K^(0)(X... 在拓扑K理论中,我们主要证明了如下结果:对任意紧致的Hausdorff空间X,存在以下同构,当n=2k(k≥0)时,K^(0)(X×S~n)≌K^(0)(x)十K^(0)(X);而当n=2k-1(k≥1)时,有K^(0)(X×S~n)≌K^(-1)(X)■K^(0)(X).当n=2k-1(k≥1)时,K^(0)(X×S~n)≌K^(-1)(X×S~n);而当n=2左(k≥0)时,K^(-1)(X×S~n)≌K^(-1)■K^(-1)(X).我们的结果依赖于以下两个事实:一是拓扑K理论中的博特周期定理和球面与欧式空间的一点紧致化同胚,这导致我们去算非紧空间作一点紧致化后的K理论;二是对任意局部紧的Hausdorff空间X总有K^(0)(X×R)≌K^(-1)(X)成立.最后,我们进一步推广了相关结论,算出环面的拓扑K理论. 展开更多
关键词 紧致性 HAUSDORFF空间 拓扑K理论
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NO<sub>2</sub>Excited State Properties Revisited: An Effect of Extra Compactified Dimensions
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作者 Hans-Georg Weber 《Journal of Modern Physics》 2017年第11期1749-1761,共13页
Experiments on NO2 reveal a substructure underlying the optically excited isolated hyperfine structure (hfs) levels of the molecule. This substructure is seen in a change of the symmetry of the excited molecule and is... Experiments on NO2 reveal a substructure underlying the optically excited isolated hyperfine structure (hfs) levels of the molecule. This substructure is seen in a change of the symmetry of the excited molecule and is represented by the two “states” and of a hfs-level. Optical excitation induces a transition from the ground state of the molecule to the excited state . However, the molecule evolves from to in a time τ0 ≈ 3 μs. Both and have the radiative lifetime τR ≈ 40 μs, but and differ in the degree of polarization of the fluorescence light. Zeeman coherence in the magnetic sublevels is conserved in the transition &rarr;, and optical coherence of and is able to affect (inversion effect) the transition &rarr;. This substructure, which is not caused by collisions with baryonic matter or by intramolecular dynamics in the molecule, contradicts our knowledge on an isolated hfs-level. We describe the experimental results using the assumption of extra dimensions with a compactification space of the size of the molecule, in which dark matter affects the nuclei by gravity. In , all nuclei of NO2 are confined in a single compactification space, and in , the two O nuclei of NO2 are in two different compactification spaces. Whereas and represent stable configurations of the nuclei,represents an unstable configuration because the vibrational motion in shifts one of the two O nuclei periodically off the common compactification space, enabling dark matter interaction to stimulate the transition &rarr;with the rate (τ0)&minus;1. We revisit experimental results, which were not understood before, and we give a consistent description of these results based on the above assumption. 展开更多
关键词 EXTRA DIMENSIONS compactification Space DARK Matter Molecular Physics
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双边生灭过程的轨道结构与构造理论 被引量:4
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作者 陈丽 薛玲霞 +1 位作者 兰社云 刘利敏 《河南大学学报(自然科学版)》 CAS 北大核心 2012年第4期337-342,共6页
给出了双边生灭过程的轨道结构,用Markov链的Ray-Knight方法得到了强Markov过程X=(Ω,F,Ft,Xt,θt,Px),它克服了在Markov链通常构造的典范链的只具有右下半连续性及仅保持部分强Markov性的缺陷,并从∞是流入的、∞是流出的、∞是自然的... 给出了双边生灭过程的轨道结构,用Markov链的Ray-Knight方法得到了强Markov过程X=(Ω,F,Ft,Xt,θt,Px),它克服了在Markov链通常构造的典范链的只具有右下半连续性及仅保持部分强Markov性的缺陷,并从∞是流入的、∞是流出的、∞是自然的、∞是正则的等几个方面指出双边生灭轨道结构与构造理论之间的对应关系. 展开更多
关键词 双边生灭过程 Martin流出边界 Ray-Knight紧化 右过程 正则点
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有限温度下10维超引力模型的稳定紧致化 被引量:2
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作者 颜骏 黄庆 陶必友 《西南交通大学学报》 EI CSCD 北大核心 1998年第5期595-600,共6页
对单圈量子与有限温度修正下的10维超引力模型紧致化中的稳定性问题进行了研究。结果表明,对于10维KalbRamond模型,通过导出有限温度等效势证明了不存在稳定的紧致化;但对具有费米子凝聚的10维超引力模型,当温度... 对单圈量子与有限温度修正下的10维超引力模型紧致化中的稳定性问题进行了研究。结果表明,对于10维KalbRamond模型,通过导出有限温度等效势证明了不存在稳定的紧致化;但对具有费米子凝聚的10维超引力模型,当温度函数满足一定的约束条件时,却可能达到稳定的紧致化。 展开更多
关键词 引力论宇宙学 温度 超引力模型 稳定紧致化
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最小Q-过程的Martin流入边界与Ray-Knight紧化 被引量:4
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作者 徐长伟 阎国军 郝淑双 《应用概率统计》 CSCD 北大核心 2011年第6期633-641,共9页
郝淑双(黄河科技学院信息工程学院,郑州,450063)本文讨论了在最小Q-过程不中断的条件下Martin流入边界与Ray-Knight紧化之间的关系,即在Martin流入边界有限的条件下,Martin流入边界中的点与Ray-Knight紧化所添加的点之间具有一一对应关系.
关键词 最小Q-过程 Martin流入边界 Ray-Knight紧化 右过程
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hit-or-miss拓扑上的度量:直接扩充 被引量:5
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作者 王延庚 卫国 李瑞 《纯粹数学与应用数学》 CSCD 北大核心 2008年第4期643-645,741,共4页
设E是Hausdorff局部紧第二可数拓扑空间.用F表示由E的所有闭子集构成的超空间,其上赋予hit-or-miss拓扑.本文引入了E上的紧型度量和F上保距扩张的概念,建立了E上度量是紧型的充分必要条件,并且证明了E上任何一个紧型度量度可以直接扩充... 设E是Hausdorff局部紧第二可数拓扑空间.用F表示由E的所有闭子集构成的超空间,其上赋予hit-or-miss拓扑.本文引入了E上的紧型度量和F上保距扩张的概念,建立了E上度量是紧型的充分必要条件,并且证明了E上任何一个紧型度量度可以直接扩充为F上的保距度量. 展开更多
关键词 Alexandroff一点紧化 hit—or-miss拓扑 紧型度量 直接扩充
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数学:连接有限与无限的金桥——读赵焕光教授等《梦想相遇无穷》有感 被引量:1
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作者 季理真 章勤琼 《数学教育学报》 CSSCI 北大核心 2014年第2期93-94,共2页
在数学中,无穷的概念非常重要,处于中心地位.从著作《梦想相遇无穷》出发,讨论无穷以及与之相关的几个概念,如完备、紧致、退化等,进而探讨当代数学中由这些概念导出的主要理论与定理.
关键词 无穷 极限 完备 紧致 退化
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紧凑型发生精馏器的实验研究 被引量:1
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作者 陈亚平 施明恒 郝志永 《东南大学学报(自然科学版)》 EI CAS CSCD 1998年第a11期50-55,共6页
提出了一种氨水吸收式制冷机紧凑化的方案,特别是采用螺旋板式换热器作为发生器和分凝器以降低发生精馏器高度的新设计,给出了采用上述改进方案所研制的乙醇蒸馏装置的实验结果.
关键词 螺旋板换热器 制冷机 发生精馏器 氨水吸收式
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