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Charge Quanta as Zeros of the Zeta Function in Bifurcated Spacetime
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作者 Otto Ziep 《Journal of Modern Physics》 2025年第2期249-262,共14页
In a fractal zeta universe of bifurcated, ripped spacetime, the Millikan experiment, the quantum Hall effect, atmospheric clouds and universe clouds are shown to be self-similar with mass ratio of about 1020. Chaotic ... In a fractal zeta universe of bifurcated, ripped spacetime, the Millikan experiment, the quantum Hall effect, atmospheric clouds and universe clouds are shown to be self-similar with mass ratio of about 1020. Chaotic one-dimensional period-doublings as iterated hyperelliptic-elliptic curves are used to explain n-dim Kepler- and Coulomb singularities. The cosmic microwave background and cosmic rays are explained as bifurcated, ripped spacetime tensile forces. First iterated binary tree cloud cycles are related to emissions 1…1000 GHz. An interaction-independent universal vacuum density allows to predict large area correlated cosmic rays in quantum Hall experiments which would generate local nuclear disintegration stars, enhanced damage of layers and enhanced air ionization. A self-similarity between conductivity plateau and atmospheric clouds is extended to correlations in atmospheric layer, global temperature and climate. 展开更多
关键词 Charge Quanta Zeta Function Cosmic Rays Cosmic Microwave Background Bifurcated spacetime
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Gravity Falls and Why the Fish Doesn’t Think: Nondeterministic Spacetime Ethics and a New Multiverse Aeon
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作者 Nicolas Vantis 《Philosophy Study》 2025年第2期91-100,共10页
Based on the Many Worlds Interpretation,I describe reality as a multilayer spacetime,where parallel layers play the role of alternative timelines.I link physics to ethics,arguing that one’s moral choices shape one’s... Based on the Many Worlds Interpretation,I describe reality as a multilayer spacetime,where parallel layers play the role of alternative timelines.I link physics to ethics,arguing that one’s moral choices shape one’s course in the multiverse.I consider one’s ethical decisions as decoherence events,leading to movement between alternative timelines,lighter(higher)or heavier(lower)realities.Sometimes in one’s curvilinear path in spacetime,one can even experience falling toward lower layers,slipping through wormholes.This theory supports free will and the simulation hypothesis.With this background,I explore the idea that a new theory of gravity might open new possibilities to shape matter and change our worldview through the invention of new technology,transforming information into waves and then into solid matter,paving the way for a new Multiverse Aeon for humanity. 展开更多
关键词 philosophy of physics DETERMINISM ETHICS GRAVITY relativistic spacetime Many Worlds Interpretation
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Second post-Newtonian motion in Simpson–Visser black-bounce spacetime
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作者 Bo Yang Chunhua Jiang Wenbin Lin 《Communications in Theoretical Physics》 2025年第9期72-80,共9页
In this paper,we present the second post-Newtonian solution for the quasi-Keplerian motion of a test particle in the regular Simpson–Visser black-bounce spacetime which has a bounce parameter a.The obtained solution ... In this paper,we present the second post-Newtonian solution for the quasi-Keplerian motion of a test particle in the regular Simpson–Visser black-bounce spacetime which has a bounce parameter a.The obtained solution is formulated in terms of orbital energy,angular momentum,and the bounce parameter of the black hole.We explicitly analyze the leading effects of the bounce parameter which has dimensions of length,on the test particle’s orbit,including the periastron advance and orbital period.Then,we apply this model to the precessing motion of OJ 287 and determine the upper limits of the dimensionless bounce parameter as a/m=3.45±0.01,where m is the mass of the regular black hole.Compared with the bound given by the periastron advance of star S2,our bound on a/m is reduced by one order of magnitude,although our upper limit of a still needs further improvement. 展开更多
关键词 Black holes Regular Simpson-Visser black-bounce spacetime Periastron advance
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Gravitational Waves Background, as Well as Some UFO, FRB and Supernova Flares, Are Due to Compressibility of the Spacetime (CoST)
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作者 Evgeny A. Novikov 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期67-70,共4页
The recently observed gravitational wave background is explained in terms of the quantum modification of the general relativity (Qmoger). Some UFO, FRB and supernova flares also can be explained in terms of Qmoger.
关键词 Gravitational Wave Background Quantum Modification of the General Relativity Compressibility of the spacetime (CoST)
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Theory and Properties of Atomic Spacetime
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作者 Sergei Yu. Eremenko 《Journal of Applied Mathematics and Physics》 2024年第6期1967-2006,共40页
Following A. Einsteins aspirations for an atomic theory, a novel theory of spacetime quantization/atomization based on finite Atomic AString Functions evolving since the 1970s is offered. Atomization Theorems allow re... Following A. Einsteins aspirations for an atomic theory, a novel theory of spacetime quantization/atomization based on finite Atomic AString Functions evolving since the 1970s is offered. Atomization Theorems allow representing polynomials, analytic functions, and solutions of General Relativity via the superposition of solitonic atoms which can be associated with flexible spacetime quanta, metriants, or elementary distortions. With multiple interpretations discussed, discrete-continuous spacetime is conceptualized as a lattice network of flexible solitonic atoms adjusting locations to reproduce different metrics. The theory may offer some variants of unified field theory under research based on Atomic AString Function where, like in string theory, fields become interconnected having a common mathematical ancestor. 展开更多
关键词 spacetime QUANTUM Atomic Function AString SOLITON Metriant Unified Theory
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Dynamic Spacetime: Key to the Mysteries of Dark Matter and Dark Energy
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作者 Tianxi Zhang 《Journal of Modern Physics》 2024年第4期416-434,共19页
Physics is a branch of science to study matter and its motion in space and time. Development of physics usually upgrades human perspective and understanding of the space and time. Einstein successfully developed speci... Physics is a branch of science to study matter and its motion in space and time. Development of physics usually upgrades human perspective and understanding of the space and time. Einstein successfully developed special and general theories of relativity and creatively promoted our perspective of spacetime from Newton’s absolute space and time to his relative spacetime. Based on redshift and distance measurements of galaxies and distant type Ia supernovae, cosmologists have suggested that our universe is expanding at an ever-increasing rate driven by a mysterious dark energy. Recently, the author has proposed that spacetime is dynamic. Spacetime is said to be absolute if it is independent of matter and motion, relative if it is affected by matter and motion, and dynamic if it mutually interacts with matter and motion. In dynamic spacetime, not only do matter and motion distort spacetime, but they are also affected by the distorted spacetime. Spacetime to be dynamic is a consequence of a deep insight to Mach’s principle, which tells us that the inertia of an object results from the gravitational interaction by the rest of the universe. Reaction of dynamic spacetime on a traveling light causes light redshift. Reaction of dynamic spacetime on a fast moving neutrino slows down the neutrino. The derived redshift-distance relation perfectly explained the measurements of distant type Ia supernovae and gamma ray bursts (GRBs) and also naturally obtained Hubble’s law as an approximate relation at small redshift. This explanation of cosmological redshift as the opposition of dynamic spacetime does not mandate the universe to be expanding and accelerating, so that it does not need the universe to be initiated from a Big Bang and driven out mainly by a mysterious dark energy. Extremely slowed down neutrinos in dynamic spacetime, when they are gravitationally trapped around clusters, galaxies, and any celestial objects, would play the role of dark matter in explaining the velocity-radius relations of galaxy’s or cluster’s rotations. 展开更多
关键词 spacetime Cosmology REDSHIFT NEUTRINO GRAVITATION Dark Matter Dark Energy
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重构方向矢量的宽带空时抗干扰方法
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作者 蓝海 黄治磊 +1 位作者 段睿 曾浩 《计算机仿真》 2025年第5期367-371,497,共6页
基于LCMV准则的传统空时抗干扰算法计算权值时只对期望信号的中心频率增益进行约束,导致仅仅靠近中心频率的频段具有最大阵列增益,且阵列增益会在整个期望信号频带内产生波动,严重影响后级接收机对期望信号的解调。新算法首先将期望信... 基于LCMV准则的传统空时抗干扰算法计算权值时只对期望信号的中心频率增益进行约束,导致仅仅靠近中心频率的频段具有最大阵列增益,且阵列增益会在整个期望信号频带内产生波动,严重影响后级接收机对期望信号的解调。新算法首先将期望信号带宽均分为多个频率子带,每个子带使用多个频率点重构空时方向矢量,再对各子带的新方向矢量进行约束,最后求解最优权矢量解,解决了传统空时算法导致的期望信号带内增益波动问题。计算机仿真证明,新方法不仅确保了期望信号带内增益的平坦度,而且具有计算复杂度低和自由度消耗小的优点。 展开更多
关键词 宽带抗干扰 波束合成 空时方向矢量重构 频率子带
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珠江流域生态风险时空演变特征研究 被引量:1
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作者 王兴丽 崔海山 《国土与自然资源研究》 2025年第2期86-90,共5页
生态风险评价在环境保护和可持续发展领域具有重要的研究地位。以珠江流域为研究区域,基于遥感影像数据和统计数据,采用“压力-状态-响应”模型构建生态风险评价体系,开展珠江流域2014、2017、2020年生态风险值的时空演变特征研究。研... 生态风险评价在环境保护和可持续发展领域具有重要的研究地位。以珠江流域为研究区域,基于遥感影像数据和统计数据,采用“压力-状态-响应”模型构建生态风险评价体系,开展珠江流域2014、2017、2020年生态风险值的时空演变特征研究。研究结果表明,(1)流域风险水平较低,在空间分布上呈现“中间低,东南-西北两侧高”的特征。(2)生态风险转移主要在低水平风险等级内发生,2014-2017年转移速度快于2017-2020年转移速度,转移幅度小,以相邻等级间相互转换为主。(3)在2014-2017年,流域中部风险改善,沿东南-西北方向风险由中央向两侧加剧,在2017-2020年,流域西部风险改善,其余区域表现为加剧。研究结果有助于了解生态风险的时空分布情况,为管理者制定针对性的风险管理措施提供科学依据。 展开更多
关键词 时空演变 生态风险 珠江流域
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HUL视角下国家工业遗产地景观特征识别研究——以易门县绿汁镇为例
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作者 姚懿珂 刘扬 《绿色科技》 2025年第3期184-190,共7页
城镇城市化、现代化导致历史遗产景观出现荒废破坏的现象,传统保护方法的局限性日益凸显。研究从遗产保护的新视角——历史性城镇景观(HUL)出发,回顾了HUL方法的概念、实施指南及其在工业遗产保护中的应用。随后,以HUL方法中强调的关联... 城镇城市化、现代化导致历史遗产景观出现荒废破坏的现象,传统保护方法的局限性日益凸显。研究从遗产保护的新视角——历史性城镇景观(HUL)出发,回顾了HUL方法的概念、实施指南及其在工业遗产保护中的应用。随后,以HUL方法中强调的关联性与层积性作为研究的切入点,以国家工业遗产地易门县绿汁镇为例,应用于工业遗产要素识别研究中:在时间要素上,梳理绿汁镇工业景观资源的产生与发展背景,识别工业价值现状及特征;在空间要素上,选取自然基底、用地分布、城镇格局、文化景观4个指标,梳理历史地图,筛选遗产资源,进行历史空间层积叠加分析,识别出以工业文化景观为主的18种景观特征类型,通过在时空双维度上对绿汁镇进行景观特征识别,为工业遗产城镇尺度的遗产保护和可持续发展研究提供了新的视角和实践路径。 展开更多
关键词 历史性城镇景观(HUL) 国家工业遗产 特征识别 时空 易门县绿汁镇
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弯曲时空下的Aubry-André-Harper动量态链
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作者 毛一屹 戴汉宁 《物理学报》 北大核心 2025年第2期75-83,共9页
Anderson局域化是凝聚态物理中一个影响深远的现象,它代表了由无序引发的本征态的根本性转变.本文提出了一个基于超冷原子动量态晶格系统的实验方案,用以实现弯曲时空下的Aubry-André-Harper(AAH)模型,并研究其中的Anderson局域化... Anderson局域化是凝聚态物理中一个影响深远的现象,它代表了由无序引发的本征态的根本性转变.本文提出了一个基于超冷原子动量态晶格系统的实验方案,用以实现弯曲时空下的Aubry-André-Harper(AAH)模型,并研究其中的Anderson局域化.得益于每对相邻动量态之间耦合的单独可操控性,动量态晶格中的耦合强度可以被编辑成幂律位置依赖的形式J_(n)∝n^(σ),从而能够有效模拟弯曲时空.动量态晶格中波包演化的数值计算结果表现出初始格点依赖的局域化性质,符合理论预测的相分离现象.通过分析波包演化动力学数据,可以观测到相分离临界格点的移动.同时,本文还提出了通过调制时空弯曲参数σ来制备本征态的方案,并在动量态晶格中进行了数值仿真.最后,在不同准周期调制相位下制备能谱中所有本征态,分析了本征态的局域化性质,验证了在能谱中共存的局域相、延展相和摇摆相.本文为在实验中研究弯曲时空下的Anderson局域化物理提供了新的可行途径. 展开更多
关键词 ANDERSON 局域化 弯曲时空 超冷原子 动量态晶格
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基于时空演绎论多囊卵巢综合征临证经验思想传薪
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作者 杨翼 邓琳雯 《国际生殖健康/计划生育杂志》 2025年第4期332-337,共6页
中医时空医学理论最早可追溯至《黄帝内经》时期,该理论认为地理环境、生活状况等因素都会影响人体的生理机能和疾病传变,被运用于疾病诊断、治疗及预防养生等方面。传统中医理论中关于多囊卵巢综合征(polycystic ovary syndrome,PCOS)... 中医时空医学理论最早可追溯至《黄帝内经》时期,该理论认为地理环境、生活状况等因素都会影响人体的生理机能和疾病传变,被运用于疾病诊断、治疗及预防养生等方面。传统中医理论中关于多囊卵巢综合征(polycystic ovary syndrome,PCOS)的时空论治的报道呈碎片化。通过查阅古代文献,对古籍中类似PCOS相关病症的特点展开溯源考证,对古今治疗方法体系进行总结,又基于“因地制宜”理论阐释地域差异对PCOS诊治思路的影响,初步揭示PCOS相关病症的时(历史沿革)空(地域特点)演变规律,进而探讨PCOS的“时空医学”概念。结合基因组学、代谢组学等现代化技术进展,将传统中医与现代中医相联系,探究PCOS相关病症的治疗发展,为现代中医生殖理论诊治PCOS的创新、突破提供参考思路。 展开更多
关键词 多囊卵巢综合征 学术思想 因地制宜 辨证论治 时空演绎
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时空注意力改进图卷积神经网络异常行为辨识
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作者 王月 王玫 +1 位作者 阚瑞祥 刘鑫 《计算机仿真》 2025年第5期415-420,558,共7页
随着世界人口老龄化程度加剧,用于老年人群体的非接触式传感设备开发越来越受到业界重视。针对老人群体摔倒、磕碰等异常行为未被及时辨识而造成严重伤痛问题,提出了一种基于时空注意力机制优化图卷积网络的异常行为辨识方法,利用人体... 随着世界人口老龄化程度加剧,用于老年人群体的非接触式传感设备开发越来越受到业界重视。针对老人群体摔倒、磕碰等异常行为未被及时辨识而造成严重伤痛问题,提出了一种基于时空注意力机制优化图卷积网络的异常行为辨识方法,利用人体骨骼的三维节点数据进行人体异常动作识别,可以辅助用户及时发现异常,采取及时的急救措施。首先,使用Kinect V2设备进行数据集的采集,相较于图像数据,骨骼三维节点数据的数据量小、传输速度快。其次,利用图卷积神经网络对骨骼节点数据和节点动态信息进行空间和时域特征提取,同时,使用注意力机制对图卷积神经网络进行优化设计。最后,将特征输入到网络模型中进行训练,对异常动作进行识别。利用公共数据集NTURGB+D对异常动作进行识别,取得了平均98.0%的识别率;在NW-UCLA数据集上得到了平均93.1%的识别率。上述法可以进行摔倒、拳打等异常动作的实时识别且具有较高的准确性。 展开更多
关键词 图卷积神经网络 注意力机制 异常动作识别 时空域信息
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从哲学角度探讨时空弯曲与四大相互作用力的关系
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作者 胡效亚 《扬州大学学报(人文社会科学版)》 2025年第2期114-128,共15页
本文基于现有的物理学、宇宙学和哲学等学科的研究成果和文献,对物质相互作用及其时空属性进行了系统的推理和研究,得出如下结论:1.将宇宙中各类物质的时空曲率进行排序,得到与时空膨胀和收缩相关的宇宙时空曲率序列(CSCS),这对推论和... 本文基于现有的物理学、宇宙学和哲学等学科的研究成果和文献,对物质相互作用及其时空属性进行了系统的推理和研究,得出如下结论:1.将宇宙中各类物质的时空曲率进行排序,得到与时空膨胀和收缩相关的宇宙时空曲率序列(CSCS),这对推论和理解宇宙的诞生、演化和物质的相互作用具有重要作用;2.光是两种时空曲率在两个相互垂直方向周期性振动前行的能量波,光是唯一能在整个CSCS中存在的物质,光是所有自然物质诞生和演化的能量提供者和驱动者,能吸收和发射光的物质才能产生时空弯曲;3.胶子、W玻色子和引力波是CSCS不同区域中光的呈现形式;4.波粒二象性等量子特性、暗物质和暗能量存在的主要依据等是低时空曲率(绝对值)区的人观察高时空曲率(绝对值)区的物理现象时产生的客观感知;5.物理学四大相互作用力均源于时空的弯曲,作用力指向时空收缩,依次分布并覆盖CSCS全过程,对宇宙的膨胀起制约和稳定作用。弱力的本质是强相互作用力;6.在“静电作用力”中,不存在“正电荷”和“负电荷”,只存在获得高时空曲率电子的高时空曲率物质(或电子)和失去电子的低时空曲率物质。“磁场”是自旋电子定向排列引起的时空曲率分布;7.原子核的稳定性、夸克的“渐近自由”、夸克禁闭和弱力等用时空曲率可获得较合理的解释。上述研究结果为物理学、天文学、哲学和认知科学等学科领域学者的研究提供了有益的参考。 展开更多
关键词 四大相互作用力 时空弯曲 相对论 宇宙大爆炸理论 时间和空间
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Kerr Black Hole Geometry Leading to Dark Matter and Dark Energy via E-Infinity Theory and the Possibility of a Nano Spacetime Singularities Reactor 被引量:8
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作者 Mohamed S. El Naschie 《Natural Science》 2015年第4期210-225,共16页
The present paper is basically a synthesis resulting from incorporating Kerr spinning black hole geometry into E-infinity topology, then letting the result bares on the vacuum zero point Casimir effect as well as the ... The present paper is basically a synthesis resulting from incorporating Kerr spinning black hole geometry into E-infinity topology, then letting the result bares on the vacuum zero point Casimir effect as well as the cosmic dark energy and dark matter density. In E-infinity theory a quantum particle is represented by a Hausdorff dimension Φ where Φ =2/(√5+1) . The quantum wave on the other hand is represented by Φ2 . To be wave and a particle simultaneously intersection theory leads us to?(Φ) (Φ)2= Φ3 which will be shown here to be twice the value of the famous Casimir force of the vacuum for a massless scalar field. Thus in the present work a basically topological interpretation of the Casimir effect is given as a natural intrinsic property of the geometrical topological structure of the quantum-Cantorian micro spacetime. This new interpretation compliments the earlier conventional interpretation as vacuum fluctuation or as a Schwinger source and links the Casimir energy to the so called missing dark energy density of the cosmos. From the view point of the present work Casimir pressure is a local effect acting on the Casimir plates constituting the local boundary condition while dark energy is nothing but the global combined effect of infinitely many quantum waves acting on the M&#246bius-like boundary of the holographic boundary of the entire universe. Since this higher dimensional M&#246bius-like boundary is one sided, there is no outside to balance the internal collective Casimir pressure which then manifests itself as the force behind cosmic expansion, that is to say, dark energy. Thus analogous to the exact irrational value of ordinary energy density of spacetime E(O)=(Φ5/2) mc2 we now have P (Casimir) = (Φ3/2)(ch/d2) where c is the speed of light, m is the mass, h is the Planck constant and d is the plate separation. In addition the new emerging geometry combined with the topology of E-infinity theory leads directly to identifying dark matter with the quasi matter of the ergosphere. As a direct consequence of this new insight E=mc2 which can be written as E = E (O) + E (D)?where the exact rational approximation is E (O)=mc2/22 is?the ordinary energy density of the cosmos and the exact rational approximation E (D)=mc2/(21/22) is the corresponding dark energy which could be subdivided once more albeit truly approximately into E(D)=mc2/(5/22)?+mc2/(16/22)??where 5 is the Kaluza Klein spacetime dimension, 16 are the bosonic extra dimensions of Heterotic superstrings and 5/22 □?22% is approximately the density of the dark matter-like energy of the ergosphere of the Kerr geometry. As for the actual design of our nano reactor, this is closely related to branching clusters of polymer, frequently called lattice animals. In other words we will have Casimir spheres instead of Casimir plates and these spheres will be basically nano particles modelling lattice animals. Here D=?4 will be regarded as spacetime dimensionality while D=6 of percolations are the compactified super string dimensions and D=8 is the dimension of a corresponding super space. 展开更多
关键词 Casimir Effect Dark ENERGY E-INFINITY Cantorian spacetime Kerr spacetime GEOMETRY ENERGY from the Ergosphere Spinning Black Holes NANO spacetime Reactors Kaluza-Klein spacetime Heterotic SUPERSTRINGS
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多视图协同的实景三维时空数据可视化平台设计
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作者 郭素蓉 《武夷学院学报》 2025年第3期48-52,共5页
为增强数据展示的可视化程度,设计基于多视图协同的实景三维时空数据可视化平台。部署三台服务器,设计可视化平台硬件部分;通过数据服务器采集实景数据源,采用数据仓库技术(extract transform load,ETL)工具,对数据备份处理;利用力导布... 为增强数据展示的可视化程度,设计基于多视图协同的实景三维时空数据可视化平台。部署三台服务器,设计可视化平台硬件部分;通过数据服务器采集实景数据源,采用数据仓库技术(extract transform load,ETL)工具,对数据备份处理;利用力导布局算法,整合数据,并将其作为三维场景搭建的基础数据,基于图数协同和图图协同两种视图协调交互模式,更新实景视图,形成批量加载的三维模型;利用ArcGIS接口,形成实景数据三维场景,采用K-means算法,对场景中的数据转换为坐标,形成实景三维时空数据的可视化平台。实验结果表明,设计实景三维时空数据可视化平台延时性较低,具有较好的应用性。 展开更多
关键词 多视图协同 实景三维时空 数据可视化平台 Scrapy框架 图数协同 矢量数据解析
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From a Dual Einstein-Kaluza Spacetime to ‘tHooft Renormalon and the Reality of Accelerated Cosmic Expansion 被引量:4
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作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2017年第8期1319-1329,共11页
We use a dual Einstein-Kaluza spacetime to calculate the exact energy density of dark energy and dark matter using a novel topological computation method. Starting from the said spacetime and ‘tHooft’s topological r... We use a dual Einstein-Kaluza spacetime to calculate the exact energy density of dark energy and dark matter using a novel topological computation method. Starting from the said spacetime and ‘tHooft’s topological renormalon as well as the corresponding symmetry group, we show how the zero set quantum particle and the empty set quantum wave interact with the vacuum and give rise to pure dark energy and pure dark matter all along with ordinary energy density of the cosmos. The consistency of the exact calculation and the accurate observations attests to the reality of ‘tHooft’s renormalon dark matter, pure dark energy and accelerated cosmic expansion. 展开更多
关键词 Accelerated COSMIC Expansion tHooft Renormalon Cantorian spacetime DARK Matter Pure DARK ENERGY Topological E-Infinity Computation Zero Set Quantum Particle Empty Set Quantum Wave Hausdorff MASS of Ordinary ENERGY Topological MASS of DARK ENERGY Mixed MASS of DARK Matter and Pure DARK ENERGY A Dual Einstein-Kaluza spacetime
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Exact Solution of a(2+1)-Dimensional Anisotropic Star in Finch and Skea Spacetime 被引量:1
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作者 Piyali Bhar Farook Rahaman +1 位作者 Ritabrata Biswas Hafiza Ismat Fatima 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第8期221-226,共6页
We provide a new class of interior solution of a(2+1)-dimensional anisotropic star in Finch and Skea spacetime corresponding to the BTZ black hole. We develop the model by considering the MIT bag model EOS and a parti... We provide a new class of interior solution of a(2+1)-dimensional anisotropic star in Finch and Skea spacetime corresponding to the BTZ black hole. We develop the model by considering the MIT bag model EOS and a particular ansatz for the metric function grrproposed by Finch and Skea [M.R. Finch and J.E.F. Skea, Class. Quantum.Grav. 6(1989) 467]. Our model is free from central singularity and satisfies all the physical requirements for the acceptability of the model. 展开更多
关键词 (2+1)-dimensional ANISOTROPIC STAR Finch and Skea spacetime
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The Emergence of Spacetime from the Quantum in Three Steps 被引量:5
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作者 Mohamed S. El Naschie 《Advances in Pure Mathematics》 2016年第6期446-454,共9页
The paper presents a very simple and straight forward yet pure mathematical derivation of the structure of actual spacetime from quantum set theory. This is achieved by utilizing elements of the topological theory of ... The paper presents a very simple and straight forward yet pure mathematical derivation of the structure of actual spacetime from quantum set theory. This is achieved by utilizing elements of the topological theory of cobordism and the Menger-Urysohn dimensional theory in conjunction with von Neumann-Connes dimensional function of Klein-Penrose modular holographic boundary of the E8E8 exceptional Lie group bulk of our universe. The final result is a lucid sharp mental picture, namely that the quantum wave is an empty set representing the surface, i.e. boundary of the zero set quantum particle and in turn quantum spacetime is simply the boundary or the surface of the quantum wave empty set. The essential difference of the quantum wave and quantum spacetime is that the wave is a simple empty set while spacetime is a multi-fractal type of infinitely many empty sets with increasing degrees of emptiness. 展开更多
关键词 Quantum spacetime Transfiite Theory Noncommutative Geometry ‘tHooft-Susskind Holography Cantorian spacetime Penrose-Connes Fractal Universe E-Infinity Theory E8 Exceptional Lie
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A Novel Spacetime Collocation Meshless Method for Solving Two- Dimensional Backward Heat Conduction Problems 被引量:1
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作者 Chihyu Liu Chengyu Ku +1 位作者 Jingen Xiao Weichung Yeih 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第1期229-252,共24页
In this article,a meshless method using the spacetime collocation for solving the two-dimensional backward heat conduction problem(BHCP)is proposed.The spacetime collocation meshless method(SCMM)is to derive the gener... In this article,a meshless method using the spacetime collocation for solving the two-dimensional backward heat conduction problem(BHCP)is proposed.The spacetime collocation meshless method(SCMM)is to derive the general solutions as the basis functions for the two-dimensional transient heat equation using the separation of variables.Numerical solutions of the heat conduction problem are expressed as a series using the addition theorem.Because the basis functions are the general solutions of the governing equation,the boundary points may be collocated on the spacetime boundary of the domain.The proposed method is verified by conducting several heat conduction problems.We also carry out numerical applications to compare the SCMM with other meshless methods.The results show that the SCMM is accurate and efficient.Furthermore,it is found that the recovered boundary data on inaccessible boundary can be obtained with high accuracy even though the over specified data are provided only at a 1/6 portion of the spacetime boundary. 展开更多
关键词 spacetime COLLOCATION MESHLESS method BACKWARD heat conduction problem basis functions.
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GLOBAL STRUCTURE OF A NODAL SOLUTIONS SET OF MEAN CURVATURE EQUATION IN STATIC SPACETIME 被引量:1
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作者 Hua LUO Guowei DAI 《Acta Mathematica Scientia》 SCIE CSCD 2022年第5期2078-2086,共9页
By bifurcation and topological methods,we study the global structure of a radial nodal solutions set of the mean curvature equation in a standard static spacetime div {a∇u√1−a^(2)|∇u|^(2)+g(∇u,∇a)/√1−a^(2)|∇u|^(2)=... By bifurcation and topological methods,we study the global structure of a radial nodal solutions set of the mean curvature equation in a standard static spacetime div {a∇u√1−a^(2)|∇u|^(2)+g(∇u,∇a)/√1−a^(2)|∇u|^(2)=λNH,with a 0-Dirichlet boundary condition on the unit ball.According to the behavior of H near 0,we obtain the global structure of sign-changing radial spacelike graphs for this problem. 展开更多
关键词 BIFURCATION static spacetime mean curvature operator nodal solution
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