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大变形中摩擦接触问题的数值模拟及应用 被引量:15
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作者 蔡中义 李明哲 陈庆敏 《应用力学学报》 CAS CSCD 北大核心 2002年第2期1-4,共4页
大变形的摩擦接触是复杂的非线性问题 ,本文介绍了一种处理摩擦接触问题的数值方法。采用接触单元技术模拟接触界面 ,基于弹塑性理论形式的非经典Coulomb摩擦定律及罚函数方法建立了摩擦接触的增量本构关系。结合大变形的增量分析格式... 大变形的摩擦接触是复杂的非线性问题 ,本文介绍了一种处理摩擦接触问题的数值方法。采用接触单元技术模拟接触界面 ,基于弹塑性理论形式的非经典Coulomb摩擦定律及罚函数方法建立了摩擦接触的增量本构关系。结合大变形的增量分析格式给出了积分摩擦接触本构方程的回映方法。这种处理摩擦接触问题的方法计算简单、使用方便。 展开更多
关键词 摩擦接触 coulomb定律 大变形 有限元 数值模拟
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用抗剪强度指标计算桩的侧阻力 被引量:15
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作者 王建华 《岩土工程技术》 2000年第3期180-182,共3页
应用库伦定律 ,采用有效应力和粘土的快剪强度计算混凝土预制桩的侧阻力 ,通过对大量桩的静载试验结果比较 ,其方法有较大的实用性。
关键词 桩基础 侧阻力 库伦定律 抗剪强度
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基于库仑定律的经验保护角法形成机理分析 被引量:8
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作者 李家启 江孟蜀 王代新 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第11期28-31,共4页
保护角法是一种确定避雷针有效保护范围的计算方法.基于闪电发生前瞬间可视为静电场,提出雷电流库仑引力比理论(①视雷电流为运动点电荷;②该电荷与避雷针尖及地面点间作用遵守库仑定律;③雷电流运动走向由其所受引力比决定),据此分析... 保护角法是一种确定避雷针有效保护范围的计算方法.基于闪电发生前瞬间可视为静电场,提出雷电流库仑引力比理论(①视雷电流为运动点电荷;②该电荷与避雷针尖及地面点间作用遵守库仑定律;③雷电流运动走向由其所受引力比决定),据此分析得到的避雷针保护半径理论式与IEC提供的经验公式一致,为避雷针经验保护角法形成机理提供了理论依据. 展开更多
关键词 避雷针 保护范围 保护角法 库仑定律
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Adapted Metrics for a Modified Coulomb/Newton’s Potential
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作者 Lucian M. Ionescu Cristina-Liliana Pripoae Gabriel Pripoae 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1311-1355,共45页
Modified Theories of Gravity include spin dependence in General Relativity, to account for additional sources of gravity instead of dark matter/energy approach. The spin-spin interaction is already included in the eff... Modified Theories of Gravity include spin dependence in General Relativity, to account for additional sources of gravity instead of dark matter/energy approach. The spin-spin interaction is already included in the effective nuclear force potential, and theoretical considerations and experimental evidence hint to the hypothesis that Gravity originates from such an interaction, under an averaging process over spin directions. This invites to continue the line of theory initiated by Einstein and Cartan, based on tetrads and spin effects modeled by connections with torsion. As a first step in this direction, the article considers a new modified Coulomb/Newton Law accounting for the spin-spin interaction. The physical potential is geometrized through specific affine connections and specific semi-Riemannian metrics, canonically associated to it, acting on a manifold or at the level of its tangent bundle. Freely falling particles in these “toy Universes” are determined, showing an interesting behavior and unexpected patterns. 展开更多
关键词 Modified Gravity Theory SPIN coulomb’s law Newton’s law Modified coulomb’s law Nuclear Force Adapted Connection Adapted Metric
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量纲关系“能量≡质量×速度×速度”的证明及推论(上) 被引量:3
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作者 王忆锋 《云光技术》 2022年第1期64-75,共12页
在质量与其他物理量无关的前提下,可以证明量纲关系“能量≡质量×速度×速度”,导出公式E=Mc^(2),其物理意义是一个质量为M的质量体以光速c运动时所具有的能量。公式E=Mc^(2)具有普遍适用性,其特例是只有一个质量体的情况,此... 在质量与其他物理量无关的前提下,可以证明量纲关系“能量≡质量×速度×速度”,导出公式E=Mc^(2),其物理意义是一个质量为M的质量体以光速c运动时所具有的能量。公式E=Mc^(2)具有普遍适用性,其特例是只有一个质量体的情况,此时该质量体以光速保持匀速直线运动,该质量体的质量是宇宙总质量,这是一个最基本的物理现象,该现象用数学语言描述就是:宇宙总能量和宇宙总质量比值的平方根等于光速,这一论断是作者提出的光速原理。以量纲关系“能量≡质量×速度×速度”为基础可以导出动量,动量对时间求导得到牛顿第二运动定律。从牛顿第二运动定律可以导出牛顿第一运动定律。基于牛顿第二运动定律定义的力的量纲,可以提出基本引力禀性常数的概念,导出一般形式的引力定律,其特例是万有引力定律。在引力定律的基础上,可以导出库仑定律以及高斯定理,并进而建立麦克斯韦方程组。基于库仑定律可以导出普朗克常数的概念。在动量和普朗克常数的基础上,可以导出普朗克定律和不确定性原理。在引力分析的基础上,可以修正牛顿第三运动定律。从波动方程出发推导了薛定谔波动方程。指出了现有物理理论体系中的矛盾和问题,并做了相应的补充和完善。 展开更多
关键词 质量体 运动定律 光速原理 引力定律 基本引力禀性常数 库仑定律 高斯定理 普朗克常数 普朗克定律 不确定性原理 麦克斯韦方程组 薛定谔波动方程
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为提高大学物理教学的学术水平而努力 被引量:6
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作者 钟锡华 《大学物理》 2018年第6期1-6,共6页
阐述了牛顿定律、引力定律和库仑定律建立的依据,以及若干重要物理量引入的依据,最后讨论了如何恰当评价对称性和守恒律在基础物理教学中的地位.本文旨在表达一种教学理念,即,对物理学所蕴含的丰富物理思想和特有思维方式的明确阐述或... 阐述了牛顿定律、引力定律和库仑定律建立的依据,以及若干重要物理量引入的依据,最后讨论了如何恰当评价对称性和守恒律在基础物理教学中的地位.本文旨在表达一种教学理念,即,对物理学所蕴含的丰富物理思想和特有思维方式的明确阐述或深刻诠释,乃是一门物理学课程学术水平的重要体现,而努力提高物理学课程的学术水平,应当成为提高大学物理教学质量的一个重要方面. 展开更多
关键词 物理思想 物理学特有思维方式 学术水平 牛顿定律 引力定律 库仑定律
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矢量积分方法在电磁学中的应用
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作者 杨超 黄永明 汤长城 《科学咨询》 2024年第12期122-125,共4页
本文分别通过矢量投影方法和矢量积分方法对电磁学问题进行求解,同时对比了两种方法在处理问题时的区别和联系,意在说明在处理电磁学问题上,矢量积分方法有直观简便的优点。为达到该目的,我们利用矢量积分方法数值地展示了均匀带电圆环... 本文分别通过矢量投影方法和矢量积分方法对电磁学问题进行求解,同时对比了两种方法在处理问题时的区别和联系,意在说明在处理电磁学问题上,矢量积分方法有直观简便的优点。为达到该目的,我们利用矢量积分方法数值地展示了均匀带电圆环的电场分布和圆形载流线圈的磁场分布,这是矢量投影方法所难以做到的。因此,我们的结果表明矢量积分法在处理矢量积分问题中更具一般性,在处理复杂问题中时具有巨大的优势。最后我们呼吁电磁学教学中应更加重视矢量积分方法的讲解和练习。 展开更多
关键词 矢量积分 库仑定律 毕奥-萨伐尔定律
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类比推理在库仑定律建立中的作用——兼论类比推理的局限性 被引量:6
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作者 兰智高 万小龙 《物理实验》 2008年第11期37-41,共5页
对相关历史资料充分考察,通过对类比推理在库仑定律建立的过程中所起作用的例证分析,尝试建立类比推理在库仑定律建立过程中的理论模型,从方法论的角度进一步探讨类比推理的功能,并对库仑定律与万有引力定律的本质差异性进行深刻剖析,... 对相关历史资料充分考察,通过对类比推理在库仑定律建立的过程中所起作用的例证分析,尝试建立类比推理在库仑定律建立过程中的理论模型,从方法论的角度进一步探讨类比推理的功能,并对库仑定律与万有引力定律的本质差异性进行深刻剖析,讨论类比推理的局限性. 展开更多
关键词 类比推理 库仑定律 万有引力定律 理论模型
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Motion State Modification of Coulomb’s Law and Dynamic Gravitation
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作者 Chi Zhang 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第3期699-707,共9页
As we know, Coulomb’s law describes the interaction between static charges. In this paper, the modified formula of Coulomb’s law in the state of charge motion is given. Based on this formula, Ampere’s law and Lore... As we know, Coulomb’s law describes the interaction between static charges. In this paper, the modified formula of Coulomb’s law in the state of charge motion is given. Based on this formula, Ampere’s law and Lorentz’s law of force are derived by pure mathematics. According to the similarity between the formula of universal gravitation and Coulomb’s law, the correction of the formula of universal gravitation under the state of motion is assumed boldly, and some inferences are made on the motion law of celestial bodies. 展开更多
关键词 coulomb’s law Moving Charge Electromagnetism Dynamic Gravitation
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Coulomb Force, Charge, and Electric Properties under Collision Space-Time
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2023年第3期686-704,共19页
We have recently published a series of papers on a theory we call collision space-time, that seems to unify gravity and quantum mechanics. In this theory, mass and energy are redefined. We have not so far demonstrated... We have recently published a series of papers on a theory we call collision space-time, that seems to unify gravity and quantum mechanics. In this theory, mass and energy are redefined. We have not so far demonstrated how to make it compatible with electric properties such as charge and the Coulomb force. The aim of this paper is to show how electric properties can be reformulated to make it consistent with collision space-time. It is shown that we need to incorporate the Planck scale into the electric constants to do so. This is also fully possible from a practical point of view, as it has recently been shown how to measure the Planck length independent of other constants and without the need for dimensional analysis. 展开更多
关键词 coulomb’s law Elementary Charge Planck Charge Electric Units Collision Space-Time
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基于库仑摩擦定律的机床导轨润滑研究
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作者 王忠峰 倪朝阳 +2 位作者 李彦镔 刘义卿 姜孝杰 《内燃机与配件》 2024年第1期52-54,共3页
机械结构磨损的本质就是有相对摩擦,减小摩擦就能降低磨损,而机床减小摩擦的方式便是有足够的润滑。润滑是机床设计和使用中特别重要的一个环节,机床的结构中包含了很多机械传动形式及各式各样的摩擦副,润滑方式的选择是其设计中的要点... 机械结构磨损的本质就是有相对摩擦,减小摩擦就能降低磨损,而机床减小摩擦的方式便是有足够的润滑。润滑是机床设计和使用中特别重要的一个环节,机床的结构中包含了很多机械传动形式及各式各样的摩擦副,润滑方式的选择是其设计中的要点,也是判断其性能优劣的一个重要指标。导轨是机床实际应用中最容易、最常见的磨损机构。本文以库伦摩擦定律为理论基础,以机床导轨的润滑为例,提出了相应的设计方法和理念,期望本文能够给机床生产厂和机床使用厂家提供设计参考,将更加高效可靠的润滑方式进行推广,推动中国制造更好的向前发展。 展开更多
关键词 库仑定律 润滑 导轨 磨损
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课程思政在电磁场与电磁波课堂教学中的设计与实践 被引量:6
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作者 宋玲玲 黄文 《大学物理》 2021年第11期36-40,共5页
本文基于专业基础课程“电磁场与电磁波”中高斯定理这一内容,开展了以“教”为主的教学活动设计,提出了引、立、破、拓、结5个教学环节,实现了知识传承、能力迁徙的教学构想.同时,从3个维度有机融入课程思政元素,不仅破解了决定立体角... 本文基于专业基础课程“电磁场与电磁波”中高斯定理这一内容,开展了以“教”为主的教学活动设计,提出了引、立、破、拓、结5个教学环节,实现了知识传承、能力迁徙的教学构想.同时,从3个维度有机融入课程思政元素,不仅破解了决定立体角的大小、正负的关键要义、闭合曲面立体角的计算等教学难点,而且还引导学生多角度看问题,助推学生正确的人生观、价值观和世界观树立,实现了“在价值传播中凝练知识底蕴,在知识传播中实现价值引领”的课程育人目标. 展开更多
关键词 课程思政 高斯定理 立体角 库仑定律
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基于物理学史的“库仑定律”教学设计
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作者 辛睿 张勇 《科教导刊》 2024年第1期58-60,共3页
库仑定律在静电学中的地位与万有引力定律在力学中的地位相当,学习库仑定律发现的历史,领会库仑等科学家在探索过程中所展现出来的科学态度、科学精神,对培养学生的物理核心素养意义重大。文章基于库仑定律发现的物理史实进行了教学设计... 库仑定律在静电学中的地位与万有引力定律在力学中的地位相当,学习库仑定律发现的历史,领会库仑等科学家在探索过程中所展现出来的科学态度、科学精神,对培养学生的物理核心素养意义重大。文章基于库仑定律发现的物理史实进行了教学设计,以期对物理教师讲授库仑定律,运用物理学史提供借鉴作用。 展开更多
关键词 库仑定律 物理学史 教学设计
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A New Theory for the Essence and Nature of Electron Charge 被引量:3
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作者 Nader Butto 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期1190-1201,共12页
Charge is a fundamental physical property of matter that is responsible for its interactions with electromagnetic fields. The real nature and the essence of charge are unknown. In this paper, a new theory is presented... Charge is a fundamental physical property of matter that is responsible for its interactions with electromagnetic fields. The real nature and the essence of charge are unknown. In this paper, a new theory is presented to describe the nature and the essence of electric charge is formulated based on the vortex model of the electron which has a finite size and has an irrotational vortex structure. This theory and the vortex model of the electron enables us, for the first time, to describe the origin of bivalency, stability, quantization, equality of the absolute values of the bivalent charges, to derive a simple formulation to calculate the electric charge based on hydrodynamics without the use any constant. The difference between negative and positive charge, is revealed and the charged particles interactions are described. The electric charge is an expression of accelerated spherical mass per area reduced by the stiffness of the vacuum which has the units <i>ε</i><sub>0</sub> ML<sup>3</sup>/T<sup>2</sup>. The calculated results based on these equations comply accurately with the experimental results. 展开更多
关键词 Electric Charge Irrotational Vortex coulomb’s law Volume Flow Rate Charge Density
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基于电动汽车两阶段充电站分配的聚合商定价方法 被引量:1
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作者 林卉 周一辰 +1 位作者 李永刚 郑皓阳 《电力系统保护与控制》 EI CSCD 北大核心 2023年第21期44-56,共13页
随着“双碳”目标的提出,电动汽车数量与日俱增,充电桩数量不足导致电动汽车充电排队时间增加、聚合商定价等问题日益凸显。针对上述问题,提出电动汽车两阶段充电站分配的聚合商定价方法。首先将聚合商与电动汽车签约模式分为完全调度... 随着“双碳”目标的提出,电动汽车数量与日俱增,充电桩数量不足导致电动汽车充电排队时间增加、聚合商定价等问题日益凸显。针对上述问题,提出电动汽车两阶段充电站分配的聚合商定价方法。首先将聚合商与电动汽车签约模式分为完全调度、奖罚机制调度和自由调度三类,考虑外部因素对电动汽车能耗影响并建立路网模型。然后采用改进A^(*)算法求解最短路径,在A^(*)算法的估价函数中引入时间因子。同时根据交通能耗、不间断行驶时间、红绿灯等待时间等因素改进估价函数。聚合商根据电动汽车的充放电需求、库伦定律得到充电站对电动汽车的吸引力。再建立电网-聚合商-电动汽车供应链,并进行两阶段的合理定价及充电站分配。最后通过算例验证聚合商定价方法可以显著提高调峰效率和聚合商利润,减少电动汽车排队时间及交通能耗。 展开更多
关键词 改进A^(*)算法 库伦定律 吸引力 充电站分配 两阶段 供应链
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基于推广的长程外力场的库仑Snake算法应用于MR心室图像的分割 被引量:3
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作者 王蓓 张立明 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2004年第1期21-26,共6页
提出了一种Snake算法的新的外部能量模型,用基于库仑定律的图像库仑场代替传统Snake中的外力场,并对该外部能量场进行了推广,根据图像的边缘特征自动设定参数,使其外力具有真正的长程性.实验结果表明,该方法提高了分割精度,减少了外部... 提出了一种Snake算法的新的外部能量模型,用基于库仑定律的图像库仑场代替传统Snake中的外力场,并对该外部能量场进行了推广,根据图像的边缘特征自动设定参数,使其外力具有真正的长程性.实验结果表明,该方法提高了分割精度,减少了外部能量场中存在的局部最小,从而大大减少了对初始轮廓的限制,同时减少了人工干预. 展开更多
关键词 图像处理 主动轮廓线模型 库仑定律 边缘提取 图像分割
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Coulomb stress changes due to the 2021 MS7.4 Maduo Earthquake and expected seismicity rate changes in the surroundings 被引量:4
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作者 Yashan FENG Xiong XIONG +1 位作者 Bin SHAN Chengli LIU 《Science China Earth Sciences》 SCIE EI CSCD 2022年第4期675-686,共12页
On May 22 nd,2021,an MS7.4 earthquake occurred near the Maduo county of the Qinghai Province,China,within the Bayan Har Block.Seismic activities have been intense in this block,thus whether the Maduo Earthquake will b... On May 22 nd,2021,an MS7.4 earthquake occurred near the Maduo county of the Qinghai Province,China,within the Bayan Har Block.Seismic activities have been intense in this block,thus whether the Maduo Earthquake will bring subsequent seismic hazards to its surrounding regions raises wide concerns.In this paper,we first calculated the Coulomb failure stress changes caused by the Maduo Earthquake on nearby faults,and estimated how much these faults are brought closer or further from their next failures based on their stressing rates.Next,we combined the Coulomb failure stress changes with the rate-state frictional law to estimate the seismicity rate in the study region in the next decade.A declustered catalogue before the Maduo Earthquake was adopted to calculate background seismicity rate,and rate-state parameters are constrained by fault slip rates.Our results show that the Maduo Earthquake increases stress accumulations in the northwestern portion of the Qingshuihe fault(0.02 MPa at maximum),the two ends of the Kunlun Mountain Pass-Jiangcuo fault(0.01 MPa at maximum),and the northwestern portion of the Maduo-Gande fault(on average~0.09 MPa),and seismicity rates are expected to increase near these faults.What is especially worth noting is the seismic hazard in the region extending from the eastern end of the Kunlun Mountain Pass-Jiangcuo fault to the Maqin-Maqu seismic gap on the Eastern Kunlun fault,which is calculated to have experienced a maximum stress increase of 0.67 MPa after the Maduo Earthquake.On the other hand,stress accumulations are reduced in the southern end of the Elashan fault,the Eastern Kunlun fault segment to the west of Maduo,and the northwestern portion of the Dari fault.Seismic hazards are expected to be low in these regions.For the study region as a whole,the probability of an M≥6 earthquake taking place in the next decade is estimated to be 59%,about twice the value calculated for the time period before the Maduo Earthquake. 展开更多
关键词 Maduo Earthquake coulomb stress change Fault slip rate Seismicity rate Rate-state frictional law
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库仑电摆实验研究 被引量:4
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作者 孙立萍 徐平 《唐山师范学院学报》 2006年第2期62-65,共4页
根据物理学史记载对库仑当年为测电引力而做的电摆实验进行了研究,在实验重现后对实验进行改进以使其更简易,更具教学意义;并对改进后的仪器做了相同的实验,分析改进前后的实验,找出各实验的优缺点。
关键词 库仑定律 电引力 库仑电器
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Q-Theory: A Connection between Newton’s Law and Coulomb’s Law? 被引量:1
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第2期632-660,共29页
Assuming a Winterberg model for space where the vacuum consists of a very stiff two-component superfluid made up of positive and negative mass planckions, Q theory is the hypothesis, that Planck charge, <i>q<... Assuming a Winterberg model for space where the vacuum consists of a very stiff two-component superfluid made up of positive and negative mass planckions, Q theory is the hypothesis, that Planck charge, <i>q<sub>pl</sub></i>, was created at the same time as Planck mass. Moreover, the repulsive force that like-mass planckions experience is, in reality, due to the electrostatic force of repulsion between like charges. These forces also give rise to what appears to be a gravitational force of attraction between two like planckions, but this is an illusion. In reality, gravity is electrostatic in origin if our model is correct. We determine the spring constant associated with planckion masses, and find that, <img src="Edit_770c2a48-039c-4cc9-8f66-406c0cfc565c.png" width="90" height="15" alt="" />, where <i>ζ</i>(3) equals Apery’s constant, 1.202 …, and, <i>n</i><sub>+</sub>(0)=<i>n</i>_(0), is the relaxed, <i>i.e.</i>, <img src="Edit_813d5a6f-b79a-49ba-bdf7-5042541b58a0.png" width="25" height="12" alt="" />, number density of the positive and negative mass planckions. In the present epoch, we estimate that, <i>n</i><sub>+</sub>(0) equals, 7.848E54 m<sup>-3</sup>, and the relaxed distance of separation between nearest neighbor positive, or negative, planckion pairs is, <i>l</i><sub>+</sub>(0)=<i>l</i><sub>_</sub>(0)=5.032E-19 meters. These values were determined using box quantization for the positive and negative mass planckions, and considering transitions between energy states, much like as in the hydrogen atom. For the cosmos as a whole, given a net smeared macroscopic gravitational field of, <img src="Edit_efc8003d-5297-4345-adac-4ac95536934d.png" width="80" height="15" alt="" />, due to all the ordinary, and bound, matter contained within the observable universe, an average displacement from equilibrium for the planckion masses is a mere 7.566E-48 meters, within the vacuum made up of these particles. On the surface of the earth, where, <i>g</i>=9.81m/s<sup>2</sup>, the displacement amounts to, 7.824E-38 met 展开更多
关键词 Extended Gravity Winterberg Model Planckion Mass Theory Modified Quantum Vacuum Planck Charge Newton’s law coulomb’s law Dark Energy
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Potential Simplification of Charge and the Coulomb Force without Affecting Predictions
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2022年第10期3003-3015,共13页
We are taking a deeper look at charge and the Coulomb force and other electric properties. There is an embedded 10<sup>-7</sup> in the Coulomb constant that we will claim is “only” needed to cancel out a... We are taking a deeper look at charge and the Coulomb force and other electric properties. There is an embedded 10<sup>-7</sup> in the Coulomb constant that we will claim is “only” needed to cancel out an embedded 10<sup>7</sup> in the charge squared. We suggest three alternatives to redefine the charge and the Coulomb constant that give considerable simplification. The Coulomb constant is not needed as a separate constant as, in the new suggested framework, it can be replaced with simply the speed of light without affecting predicted output values. We also point out potential issues with the 2019 redefinition of the Coulomb constant and elementary charge. This is not meant conclusive but to open up for further discussion on how one potential can simplify parts of physics. 展开更多
关键词 coulomb law coulomb Constant Elementary Charge Planck Charge Planck Voltage Electric Units
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