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Enhancement of electron–positron pairs in combined potential wells with linear chirp frequency
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作者 王莉 李烈娟 +4 位作者 麦丽开·麦提斯迪克 安荣 李静静 谢柏松 张丰收 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期153-160,共8页
Effect of linear chirp frequency on the process of electron–positron pairs production from vacuum is investigated by the computational quantum field theory.With appropriate chirp parameters,the number of electrons cr... Effect of linear chirp frequency on the process of electron–positron pairs production from vacuum is investigated by the computational quantum field theory.With appropriate chirp parameters,the number of electrons created under combined potential wells can be increased by two or three times.In the low frequency region,frequency modulation excites interference effect and multiphoton processes,which promotes the generation of electron–positron pairs.In the high frequency region,high frequency suppression inhibits the generation of electron–positron pairs.In addition,for a single potential well,the number of created electron–positron pairs can be enhanced by several orders of magnitude in the low frequency region. 展开更多
关键词 electron–positron pairs linear chirp frequency the computational quantum field theory
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Solitary kinetic Alfvén waves in a dense electron–positron–ion plasma with degenerate electrons and positrons
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作者 Monzurul K AHMED Om P SAH 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第12期42-49,共8页
Through the use of a reductive perturbation technique, solitary kinetic Alfvén waves(KAWs) are investigated in a low but finite b(particle-to-magnetic pressure ratio) dense electron–positron–ion plasma where el... Through the use of a reductive perturbation technique, solitary kinetic Alfvén waves(KAWs) are investigated in a low but finite b(particle-to-magnetic pressure ratio) dense electron–positron–ion plasma where electrons and positrons are degenerate. The degenerate plasma model considered here permits the existence of sub-Alfvénic compressive solitary KAWs. The influence of r(equilibrium positron-to-ion density ratio), sF(electron-to-positron Fermi temperature ratio), b and obliqueness parameter lzon various characteristics of solitary KAWs are examined through numerical plots. We have shown that there exists a critical value of lzat which a soliton width attains its maximum value which decreases with an increase in r and sF.It is also found that solitons with a higher energy propagate more obliquely in the direction of an ambient magnetic field. The results of the present investigation may be useful for understanding low frequency nonlinear electromagnetic wave propagation in magnetized electron–positron–ion plasmas in dense stars. Specifically, the relevance of our investigation to a pulsar magnetosphere is emphasized. 展开更多
关键词 kinetic Alfvén waves solitons electron–positron–ion plasma degenerate plasma Thomas–Fermi approximation
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Enhanced electron–positron pair production by frequency chirping in one-and two-color laser pulse fields 被引量:2
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作者 Nuriman Abdukerim 李子良 谢柏松 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期48-55,共8页
Enhanced electron–positron pair production by frequency chirping in one- and two-color laser pulse fields is investigated by solving the quantum Vlasov equation. A small frequency chirp shifts the momentum spectrum a... Enhanced electron–positron pair production by frequency chirping in one- and two-color laser pulse fields is investigated by solving the quantum Vlasov equation. A small frequency chirp shifts the momentum spectrum along the momentum axis. The positive and negative frequency chirp parameters play the same role in increasing the pair number density. The sign change of the frequency chirp parameter at the moment t = 0 leads the pulse shape and momentum spectrum to be symmetric, and the number density to be increased. The number density of produced pairs in the two-color pulse field is much higher than that in the one-color pulse field and the larger frequency chirp pulse field dominates more strongly. In the two-color pulse fields, the relation between the frequency ratio of two colors and the number density is not sensitive to the parameters of small frequency chirp added in either a low frequency strong field or a high frequency weak field but sensitive to the parameters of large frequency chirp added in a high frequency weak field. 展开更多
关键词 双色激光场 频率啁啾 脉冲场 电子对 单脉冲 Vlasov方程 啁啾参数 动量谱
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 electron positron Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS Klein GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow ATTRACTION REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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An Electron Model Consistent with Electron-Positron Pair Production from High Energy Photons 被引量:1
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作者 Donald Bowen Robert V. Mulkern 《Journal of Modern Physics》 2015年第9期1334-1342,共9页
This is a rotating charge loop model of an electron which explains the electron’s de Broglie base frequency to an accuracy of over 6 decimal places. The model also predicts the magnetic moment of the electron to over... This is a rotating charge loop model of an electron which explains the electron’s de Broglie base frequency to an accuracy of over 6 decimal places. The model also predicts the magnetic moment of the electron to over 6 decimal places and helps explain the transition from a purely electromagnetic photon to a fermion state of matter. The model also explains how charge and spin are conserved in the transition. Finally, this concept might be extended to explain the muon and tau higher energy states of the electron as well. 展开更多
关键词 electron positron Loop MUON Tau Pair Production Photon FERMION Magnetic Moment De BROGLIE
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A Prototype Electron-Positron Fusion Reactor 被引量:1
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期949-951,共3页
In a previous paper [1] we established the possibility of the advantage of using the bombardment of electron-positron beams to produce commercial electrical energy. We consider the design of such a prototype reactor u... In a previous paper [1] we established the possibility of the advantage of using the bombardment of electron-positron beams to produce commercial electrical energy. We consider the design of such a prototype reactor using 100 KJ laser beams to produce electron-positron beams that are sent to the reactor to release the 100 KJ of energy in the form of Xrays, which creates the high temperature and pressure needed to ignite the deuterium-tritium pellets for the fusion reaction. 展开更多
关键词 electron-positron Prototype Reactor Laser Beams
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Dynamics of laser beams in inhomogeneous electron positron ion plasmas
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作者 成丽红 唐荣安 +1 位作者 杜宏娥 薛具奎 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期315-320,共6页
Nonlinear interaction of laser and electron–positron–ion plasmas is investigated by invoking the variational principle and numerical simulation, in terms of a nonlinear Schr o¨dinger equation with inhomogeneiti... Nonlinear interaction of laser and electron–positron–ion plasmas is investigated by invoking the variational principle and numerical simulation, in terms of a nonlinear Schr o¨dinger equation with inhomogeneities effect. It is shown that the plasma inhomogeneity has great influence on the laser beam dynamics. The laser beam can be self-trapped, focused, or defocused depending on the inhomogeneity character. The linearly decreasing axial plasma density makes the laser beam defocus, while the linearly increasing axial plasma density results in self-trapping of the beam. The self-focusing of the trapped beam is found in a high-density region. For the Gaussian types of density distribution, the beam field submits nonlinearly oscillating regime. The results provide an efficient way to manipulate the dynamics of laser beam propagating in plasma. 展开更多
关键词 等离子体密度 激光束 非均匀性 正电子 动力学 非线性相互作用 非线性薛定谔方程 不均匀性
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Enhanced electron positron pair creation by the frequency chirped laser pulse
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作者 姜敏 谢柏松 +1 位作者 桑海波 李子良 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期125-129,共5页
Based on the quantum Vlasov equation,the effect of frequency chirp on electron–positron pair production is investigated.The cycle parameter,which characterizes the laser field cycle degree within the pulse,is also co... Based on the quantum Vlasov equation,the effect of frequency chirp on electron–positron pair production is investigated.The cycle parameter,which characterizes the laser field cycle degree within the pulse,is also considered.In both supercycle and subcycle laser pulses the frequency chirp can greatly enhance the momentum distribution function of created pairs and the pair number density.The pair number density created by a supercycle laser pulse is larger than that by a subcycle pulse under the same laser frequency and chirping.There exists an optimal cycle parameter corresponding to the maximum value of the created pair number density for different chirp rates.It is found that the pair number density is sensitive/insensitive to chirping rate when the cycle parameter lies below/above the optimal one. 展开更多
关键词 啁啾激光脉冲 正负电子对 频率啁啾 动量分布函数 循环参数 线性调频 光脉冲产生 准周期
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Linear tearing modes in an electron-positron plasma
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作者 宋桂良 蔡辉山 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第4期23-27,共5页
The general dispersion of tearing modes due to the effects of electron inertia and resistivity in pair plasmas is derived analytically,and is discussed in two cases:△'■1 and△'■1,where△'is the instabil... The general dispersion of tearing modes due to the effects of electron inertia and resistivity in pair plasmas is derived analytically,and is discussed in two cases:△'■1 and△'■1,where△'is the instability criterion of the tearing mode.It is found that the conditions under which either resistivity or electron inertia dominates depend strongly on the limit of A'considered. 展开更多
关键词 电子等离子体 撕裂模 线性 稳定性判据 电阻率 惯性
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Nonlinear ion-acoustic solitary waves in an electron-positron-ion plasma with relativistic positron beam
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作者 Ridip Sarma Amar P Misra Nirab C Adhikary 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期471-476,共6页
The propagation characteristics of nonlinear ion–acoustic(IA) solitary waves(SWs) are studied in thermal electron–positron–ion plasma considering the effect of relativistic positron beam. Starting from a set of flu... The propagation characteristics of nonlinear ion–acoustic(IA) solitary waves(SWs) are studied in thermal electron–positron–ion plasma considering the effect of relativistic positron beam. Starting from a set of fluid equations and using the reductive perturbation technique, we derive a Korteweg–de Vries(KdV) equation which governs the evolution of weakly nonlinear IA SWs in relativistic beam driven plasmas. The properties of the IA soliton are studied, and it is shown that the presence of relativistic positron beam significantly modifies the characteristics of IA solitons. 展开更多
关键词 弱非线性 正电子 相对论 离子 血浆 波浪 独居 声学
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Constraining Galactic pγ Interactions with Cosmic Ray Electron and Positron Spectra
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作者 Nayantara Gupta 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第2期153-158,共6页
高精力质子由宇宙的光线的各种各样的来源生产了,例如,超新星残余,脉冲星风星云,活跃星群的原子核和 gamma 光线爆炸,参予 p&#947; 和 pp 相互作用。尽管 pp 相互作用可以是在我们的星系的主导的机制, p&#947; 过程怎么... 高精力质子由宇宙的光线的各种各样的来源生产了,例如,超新星残余,脉冲星风星云,活跃星群的原子核和 gamma 光线爆炸,参予 p&#947; 和 pp 相互作用。尽管 pp 相互作用可以是在我们的星系的主导的机制, p&#947; 过程怎么重要,是不清楚的。我们证明总数的部分上的上面的界限在宇宙的光线的所有星群的天体物理学的来源内参予 p&#947; 相互作用的质子数是 10% 。 展开更多
关键词 宇宙射线 质子 电子 正电子 星系
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Non-Linear Ion-Acoustic Solitary Waves in Electron-Positron-Ion Plasma with Non-Thermal Electrons
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作者 S. K. Anguma I. Habumugisha +2 位作者 L. Nazziwa E. Jurua N. Noreen 《Journal of Modern Physics》 2017年第6期892-902,共11页
Ion-acoustic solitary (IAS) waves in electron-positron-ion (e-p-i) plasma have been of interest to many researchers probably due to their relevance in understanding the Universe. However, the study of non-linear ion-a... Ion-acoustic solitary (IAS) waves in electron-positron-ion (e-p-i) plasma have been of interest to many researchers probably due to their relevance in understanding the Universe. However, the study of non-linear ion-acoustic waves in e-p-i plasma with non-thermal electrons has not been adequately studied. A theoretical investigation on non-linear IAS waves in e-p-i plasma comprising of warm inertial adiabatic fluid ions and electrons that are kappa distributed, and Boltzman distributed positron is presented here using the Sagdeev potential technique. It was found that existence domains of finite amplitude IAS waves were confined within the limits of minimum and maximum Mach numbers with varying k values. For lower values of k, the amplitude of the solitary electrostatic potential structures increased as the width decreased, while for high values, the potential amplitude decreased as the width of the solitary structure increased. 展开更多
关键词 NON-THERMAL electronS Ion-Acoustic Solitary Waves electron-positron-Ion Plasmas
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Exploring positron characteristics utilizing two new positron–electron correlation schemes based on multiple electronic structure calculation methods
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作者 张文帅 谷冰川 +2 位作者 韩小溪 刘建党 叶邦角 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期535-542,共8页
We make a gradient correction to a new local density approximation form of positron–electron correlation. The positron lifetimes and affinities are then probed by using these two approximation forms based on three el... We make a gradient correction to a new local density approximation form of positron–electron correlation. The positron lifetimes and affinities are then probed by using these two approximation forms based on three electronic-structure calculation methods, including the full-potential linearized augmented plane wave(FLAPW) plus local orbitals approach,the atomic superposition(ATSUP) approach, and the projector augmented wave(PAW) approach. The differences between calculated lifetimes using the FLAPW and ATSUP methods are clearly interpreted in the view of positron and electron transfers. We further find that a well-implemented PAW method can give near-perfect agreement on both the positron lifetimes and affinities with the FLAPW method, and the competitiveness of the ATSUP method against the FLAPW/PAW method is reduced within the best calculations. By comparing with the experimental data, the new introduced gradient corrected correlation form is proved to be competitive for positron lifetime and affinity calculations. 展开更多
关键词 结构计算 正负电子 相关方 全势线性缀加平面波 正电子寿命 FLAPW 局域密度近似 多重
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Role of the Reference Frame in Angular Photon Distribution at Electron-Positron Annihilation
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作者 Andrey N. Volobuev Eugene S. Petrov Eugene L. Ovchinnikov 《Journal of Modern Physics》 2014年第6期353-358,共6页
The reasons of angular photon distribution occurrence at electron-positron annihilation are considered. It is shown that angular photon distribution is consequence of Doppler’s effect in the reference frame of the el... The reasons of angular photon distribution occurrence at electron-positron annihilation are considered. It is shown that angular photon distribution is consequence of Doppler’s effect in the reference frame of the electron and positron mass center. In the reference frame bound with moving electron the angular photon distribution is absent. But it is replaced by the Doppler’s shift of photons frequencies. The received results are applied to the analysis of a positron-emission tomograph work. 展开更多
关键词 ANNIHILATION electron positron PHOTON Doppler’s Effect ANGULAR PHOTON DISTRIBUTION positron-Emission Tomograph
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The Exact Similarity between the Positron and the Electron Equations in a P and the T Violations
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作者 Roger Boudet 《Journal of Modern Physics》 2012年第8期774-776,共3页
Using in CPT a P and T violations we show that the equation of the positron is exactly the same as the one of the electron, on the condition that both the sign of the charge and the electromagnetic potential are chang... Using in CPT a P and T violations we show that the equation of the positron is exactly the same as the one of the electron, on the condition that both the sign of the charge and the electromagnetic potential are changed. As a consequence the velocities are both in direction to the future and the masses are both positive and, in similar experiences, the behaviours of the two particles are the same. These theoretical results are in quite agreements with the experiments of the LEP. 展开更多
关键词 positron the electron EQUATIONS
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Canonical Angular Momentum of Electron, Positron and the Gamma Photon
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作者 Ziya Saglam Mesude Saglam 《Journal of Modern Physics》 2016年第1期134-138,共5页
We calculate the canonical angular momentum of a free electron, positron and gamma photon. We show that for any particle with charge q the canonical angular momentum (J<sub>c</sub>) is written as the summa... We calculate the canonical angular momentum of a free electron, positron and gamma photon. We show that for any particle with charge q the canonical angular momentum (J<sub>c</sub>) is written as the summation of the kinetic angular momentum (J<sub>kin</sub>) and the intrinsic quantum flux dependent terms. In terms of the z-components this can be written as . For a free electron (e<sup>-</sup>) and a positron (e<sup>+</sup>) depending on the spin orientation we find that:;;and respectively. Similarly for a gamma (γ) photon, propagating in z direction with an angular frequency ω, the canonical angular momentum is found to be: , here the (+) and (-) signs stand for the right and left hand circular helicity respectively. 展开更多
关键词 Magnetic Moment Quantum Flux Gamma Photons Canonical Angular Momentum electron-positron Annihilation Right (Left) Hand Circular Helicity
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双振荡场产生正负电子对的理论研究
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作者 李传可 林南省 +2 位作者 周鲜鲜 江淼 李英骏 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第4期151-160,共10页
在强电磁场下真空产生正负电子对的研究中,多场的组合扮演重要的角色.本文运用计算量子场论方法在全时空数值求解狄拉克方程,研究了两个空间分离的局域化振荡电场击穿真空产生正负电子对的过程.结果表明通过选取合适的场参数,两场的相... 在强电磁场下真空产生正负电子对的研究中,多场的组合扮演重要的角色.本文运用计算量子场论方法在全时空数值求解狄拉克方程,研究了两个空间分离的局域化振荡电场击穿真空产生正负电子对的过程.结果表明通过选取合适的场参数,两场的相互作用可以显著增强正负电子对的产生.两场的相互作用使产生正负电子对的动量分布曲线出现了周期性的振荡,并导致了非对称的多光子跃迁过程.通过含时微扰理论分析得出,正负电子对的动量分布的周期性振荡可由电场宽度、电场频率和两场间距共同决定.两场间距能够改变正负电子对动量分布的变化周期,随着两场间距的增大,产生正负电子对的动量(能量)的单一性得到优化;电场宽度不仅影响正负电子对动量分布的峰谷高度差,还会改变其在动量空间峰值的展宽;根据能量守恒定律,电场频率的增大使得产生粒子对的动量随之变大.因此,通过选择合适电场参数可以抑制或加强特定动量分布的正负电子对,这为今后的实验设计提供了重要的理论指导. 展开更多
关键词 正负电子对产生 计算量子场论 强场物理
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用经典力学计算氢原子和电子偶素基态能量
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作者 何帅 《山西化工》 CAS 2024年第4期136-137,140,共3页
笔者对云南大学陈景教授的用经典力学计算氢分子键长、键能及力常数的理论模型进行推广,采用经典力学的方法,分别计算了氢原子和电子偶素的基态能量,得到的理论计算值分别为13.6 eV和6.8 eV,理论计算值与实验值一致。理论模型直观,计算... 笔者对云南大学陈景教授的用经典力学计算氢分子键长、键能及力常数的理论模型进行推广,采用经典力学的方法,分别计算了氢原子和电子偶素的基态能量,得到的理论计算值分别为13.6 eV和6.8 eV,理论计算值与实验值一致。理论模型直观,计算方法简单且计算结果精确,同时未添加任何人为性的参数。 展开更多
关键词 氢原子 电子偶素 基态能量 质子 电子 正电子 负电子
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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1050-1062,共13页
The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has... The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta. 展开更多
关键词 ELECTROSTATIC electron positron COULOMB Force ATTRACTION REPULSION Wave Function Electric Magnetic Radiation Pressure Shell THEOREM 3D Computer Model Quantum
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Calculation of <i>G</i>Gravity Constant from the Mass and Electron Charge, and Fine Structure Constant 被引量:1
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作者 Valentino Straser 《Journal of Modern Physics》 2021年第8期1172-1181,共10页
This study proposes, from the theoretical point of view, the calculation of the gravitational constant <em>G</em>, made starting from the charge and the electron mass, taking the constant of the Fine Struc... This study proposes, from the theoretical point of view, the calculation of the gravitational constant <em>G</em>, made starting from the charge and the electron mass, taking the constant of the Fine Structure into examination. In the empty space, couples of virtual positron electrons dematerialize, giving virtual photon origin. They, at their time, will become electrons, positrons and so on. These transformations are made keeping the board of their “amount of movement” and when they meet the matter, these couples come, reissued depending on the field and on the matter mass. The matter is the change of the trend of their gyromagnetic movement relationship which puts under pressure. In presence of two masses, this gyromagnetic movement relationship is already partially oriented towards the other mass. From here a force is established between these two masses that give as calculated constant equal to 6.678532. This value of <em>G</em>, obtained leaving from the charge and the electron mass, is very near the experimental values estimated in these last decades regard the value of the gravitational constant of <em>G</em>. 展开更多
关键词 electron positron Gravitational Constant String Theory Theory of Everything Fine Structure Constant
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