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Redefining the Event Horizon
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作者 Shiv Raj Aryan 《International Journal of Astronomy and Astrophysics》 2013年第4期392-394,共3页
Presented herein is a new and independent derivation of equation for the radius of Black Holes, i.e. the event horizon of black holes. The equation has been derived by formulating the relativistic equation of escape v... Presented herein is a new and independent derivation of equation for the radius of Black Holes, i.e. the event horizon of black holes. The equation has been derived by formulating the relativistic equation of escape velocity derived from the relativistic equations for gravitational potential and kinetic energy. Based upon that, it is now shown that the actual size of a black hole, as determined by its event horizon, is exactly half the value predicted by the escape velocity equation used in the Newtonian mechanics. It proves that the actual radius of a black hole is exactly one half of the Schwarzschild radius. 展开更多
关键词 event horizon BLACK HOLE LORENTZ Transformation RELATIVITY
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Entropy Change of Non-Spinning Black Holes w.r.t. the Radius of Event Horizon in AGN
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作者 Dipo Mahto Md. Shams Nadeem +2 位作者 Umakant Prasad Abhay Kumar K. M. Singh 《Journal of Modern Physics》 2013年第3期321-326,共6页
In this research paper, we have used the formula for the change in entropy of Non-spinning black holes with respect to the change in the radius of event horizon (Mahto et al. 2012) and entropy of black holes (Hawking ... In this research paper, we have used the formula for the change in entropy of Non-spinning black holes with respect to the change in the radius of event horizon (Mahto et al. 2012) and entropy of black holes (Hawking 1973 & Mahto et al. 2012) to calculate their values in Active Galactic Nuclei (AGN) which shows that the variation of change in entropy of black holes with respect to the radius of the event horizon/entropy of black holes with increasing the values of the radius of the event horizon of different test Non-spinning black holes are like a wave-pattern. 展开更多
关键词 RADIUS of event-horizon AGN Entropy
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Modified <i>f(R)</i>Gravity and Thermodynamics of Time-Dependent Wormholes at Event Horizon
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作者 Hamidreza Saiedi 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期708-714,共7页
In the context of modified gravity theory, we study time-dependent wormhole spacetimes in the radiation background. In this framework, we attempt to generalize the thermodynamic properties of time-dependent wormholes ... In the context of modified gravity theory, we study time-dependent wormhole spacetimes in the radiation background. In this framework, we attempt to generalize the thermodynamic properties of time-dependent wormholes in gravity. Finally, at event horizon, the rate of change of total entropy has been discussed. 展开更多
关键词 f(R) GRAVITY TIME-DEPENDENT WORMHOLES Thermodynamics event horizon
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The quantum nonthermal radiation and horizon surface gravity of an arbitrarily accelerating black hole with electric charge and magnetic charge
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作者 谢志堃 潘伟珍 杨学军 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期567-571,共5页
Using a new tortoise coordinate transformation,we discuss the quantum nonthermal radiation characteristics near an event horizon by studying the Hamilton-Jacobi equation of a scalar particle in curved space-time,and o... Using a new tortoise coordinate transformation,we discuss the quantum nonthermal radiation characteristics near an event horizon by studying the Hamilton-Jacobi equation of a scalar particle in curved space-time,and obtain the event horizon surface gravity and the Hawking temperature on that event horizon.The results show that there is a crossing of particle energy near the event horizon.We derive the maximum overlap of the positive and negative energy levels.It is also found that the Hawking temperature of a black hole depends not only on the time,but also on the angle.There is a problem of dimension in the usual tortoise coordinate,so the present results obtained by using a correct-dimension new tortoise coordinate transformation may be more reasonable. 展开更多
关键词 tortoise coordinate transformation black hole quantum nonthermal radiation event horizon surface gravity
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Generalized Newton’s Theory of Universal Gravitation and Black Holes
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作者 Lenser Aghalovyan 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期126-137,共12页
The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with... The Newton’s theory of universal gravitation is generalized. Significantly strong at short distances central interaction of bodies and particles is established in comparison with Newtonian. A connection is found with Black Holes, with the horizon of events. Possibility of systematization of all Black Holes is shown. An illustration is given on the example of Black Hole S<sub>gr</sub>A*. 展开更多
关键词 GRAVITATION Central Interaction Escape Velocity Black Hole horizon of events
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The Correct Reissner-Nordstrøm, Kerr and Kerr-Newman Metrics
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作者 Carlo Maria Pace 《Journal of Modern Physics》 2024年第10期1502-1522,共21页
In a very recent article of mine I have corrected the traditional derivation of the Schwarzschild metric thus arriving to formulate a correct Schwarzschild metric different from the traditional Schwarzschild metric. I... In a very recent article of mine I have corrected the traditional derivation of the Schwarzschild metric thus arriving to formulate a correct Schwarzschild metric different from the traditional Schwarzschild metric. In this article, starting from this correct Schwarzschild metric, I also propose corrections to the other traditional Reissner-Nordstrøm, Kerr and Kerr-Newman metrics on the basis of the fact that these metrics should be equal to the correct Schwarzschild metric in the borderline case in which they reduce to the case described by this metric. In this way, we see that, like the correct Schwarzschild metric, also the correct Reissner-Nordstrøm, Kerr and Kerr-Newman metrics do not present any event horizon (and therefore do not present any black hole) unlike the traditional Reissner-Nordstrøm, Kerr and Kerr-Newman metrics. 展开更多
关键词 General Theory of Relativity SCHWARZSCHILD Reissner-Nordstrøm KERR Kerr-Newman Metric event horizon Black Hole
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Where Is Phase Velocity in Minkowski Space?
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作者 Antony J. Bourdillon 《Journal of Modern Physics》 2024年第10期1555-1566,共12页
In the special theory of relativity, massive particles can travel at neither the speed of light c nor faster. Meanwhile, since the photon was quantized, many have thought of it as a point particle. How pointed? The id... In the special theory of relativity, massive particles can travel at neither the speed of light c nor faster. Meanwhile, since the photon was quantized, many have thought of it as a point particle. How pointed? The idea could be a mathematical device or physical simplification. By contrast, the preceding notion of wave-group duality has two velocities: a group velocity vg and a phase velocity vp. In light vp = vg = c;but it follows from special relativity that, in massive particles, vp > c. The phase velocity is the product of the two best measured variables, and so their product constitutes internal motion that travels, verifiably, faster than light. How does vp then appear in Minkowski space? For light, the spatio-temporal Lorentz invariant metric is s2=c2t2−x2−y2−z2, the same in whatever frame it is viewed. The space is divided into 3 parts: firstly a cone, symmetric about the vertical axis ct > 0 that represents the world line of a stationary particle while the conical surface at s = 0 represents the locus for light rays that travel at the speed of light c. Since no real thing travels faster than the speed of light c, the surface is also a horizon for what can be seen by an observer starting from the origin at time t = 0. Secondly, an inverted cone represents, equivalently, time past. Thirdly, outside the cones, inaccessible space. The phase velocity vp, group velocity vg and speed of light are all equal in free space, vp = vg = c, constant. By contrast, for particles, where causality is due to particle interactions having rest mass mo > 0, we have to employ the Klein-Gordon equation with s2=c2t2−x2−y2−z2+mo2c2. Now special relativity requires a complication: vp.vg = c2 where vg c and therefore vp > c. In the volume outside the cones, causality due to light interactions cannot extend beyond the cones. However, since vp > c and even vp >> c when wavelength λ is long, extreme phase velocities are then limited in their causal effects by the particle uncertainty σ, i.e. to vgt ± σ/ω, where ω is the particle angular frequency. This is the first time the phase range has been described for a massive particle. 展开更多
关键词 event horizon Scattering Range Wave Packet Phase Velocity Group Velocity Dispersion Dynamics Quantum Physics
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The Unified Field
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作者 Joseph H. (Cass) Forrington 《Journal of Modern Physics》 2024年第7期1010-1035,共26页
This is a Unified Field description based on the holographic Time Dilation Cosmology, TDC, model, which is an eternal continuum evolving forward in the forward direction of time, at the speed of light, c, at an invari... This is a Unified Field description based on the holographic Time Dilation Cosmology, TDC, model, which is an eternal continuum evolving forward in the forward direction of time, at the speed of light, c, at an invariant 1 s/s rate of time. This is the Fundamental Direction of Evolution, FDE. There is also an evolution down time dilation gradients, the Gravitational Direction of Evolution, GDE. These evolutions are gravity, which is the evolutionary force in time. Gravitational velocities are compensation for the difference in the rate of time, dRt, in a dilation field, and the dRtis equal to the compensatory velocity’s percentage of c, and is a measure of the force in time inducing the velocity. In applied force induced velocities, the dRt is a measure of the resistance in time to the induced velocity, which might be called “anti-gravity” or “negative gravity”. The two effects keep the continuum uniformly evolving forward at c. It is demonstrated that gravity is already a part of the electromagnetic field equations in way of the dRt element contained in the TDC velocity formula. Einstein’s energy formula is defined as a velocity formula and a modified version is used for charged elementary particle solutions. A time dilation-based derivation of the Lorentz force ties gravity directly to the electromagnetic field proving the unified field of gravity and the EMF. It is noted how we could possibly create gravity drives. This is followed by a discussion of black holes, proving supermassive objects, like massive black hole singularities, are impossible, and that black holes are massless Magnetospheric Eternally Collapsing Objects (MECOs) that are vortices in spacetime. . 展开更多
关键词 Unified Field GRAVITY Anti-Gravity Astrophysics Einstein General Relativity Special Relativity Galactic Rotation Velocities Time Dilation SPACETIME Space Time Spacetime Continuum Quantum Continuum MECO Black Hole event horizon Timelike Spacelike Lightlike
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The Solution of the Einstein’s Equations in the Vacuum Region Surrounding a Spherically Symmetric Mass Distribution
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作者 Carlo Maria Pace 《Journal of Modern Physics》 2024年第9期1353-1374,共22页
In this article, we address the solution of the Einstein’s equations in the vacuum region surrounding a spherically symmetric mass distribution. There are two different types of mathematical solutions, depending on t... In this article, we address the solution of the Einstein’s equations in the vacuum region surrounding a spherically symmetric mass distribution. There are two different types of mathematical solutions, depending on the value of a constant of integration. These two types of solutions are analysed from a physical point of view. The comparison with the linear theory limit is also considered. This leads to a new solution, different from the well known one. If one considers the observational data in the weak field limit this new solution is in agreement with the available data. While the traditional Schwarzschild solution is characterized by a horizon at r=2GM/c2, no horizon exists in this new solution. 展开更多
关键词 General Theory of Relativity Schwarzschild Solution event horizon Black Hole
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沂沭断裂带及其近区地震事件地层的时空分布及意义 被引量:10
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作者 田洪水 祝介旺 +3 位作者 王华林 张增奇 张邦花 张慎河 《古地理学报》 CAS CSCD 北大核心 2017年第3期393-417,共25页
沂沭断裂带纵贯山东省中部,属郯庐断裂带中段。在沂沭断裂带及其近区新元古代—新生代的沉积地层中,到目前,已识别出25个地震事件层位。这些地震事件层位的名称取自不同年代或年龄的含地震记录的岩石地层。大多数地震记录是震积岩,少部... 沂沭断裂带纵贯山东省中部,属郯庐断裂带中段。在沂沭断裂带及其近区新元古代—新生代的沉积地层中,到目前,已识别出25个地震事件层位。这些地震事件层位的名称取自不同年代或年龄的含地震记录的岩石地层。大多数地震记录是震积岩,少部分为震火山岩,它们的时空分布支持该断裂带生成—活动与发展历史分2个阶段:古郯庐断裂带阶段(新元古代—古生代)和中—新生代阶段。新元古代初鲁中至苏皖北部NNE向韧性剪切带的形成,沟通了秦岭大别与苏鲁洋间的NEE走向的转换断层,可能是沂沭断裂带或古郯庐断裂带的成因机制。在纵向上,古郯庐断裂带阶段形成了8个地震事件层位,其中5个地震事件层位较密集地分布于南华系至中下寒武统;中—新生代阶段形成了17个地震事件层位,其中12个层位较密集的分布于白垩系—古近系。因此,南华纪—早中寒武世、白垩纪—古近纪分别为2个发展阶段的强地震事件频繁发生时段。在这2个发展阶段,该断裂带地震活动的动力来源不同:古郯庐断裂带阶段主要源于华北与华南板块的相向运动与碰撞;中—新生代阶段主要源于太平洋板块向欧亚大陆板块下俯冲。在横向上,有15个(占60%)地震事件层位分布在此断裂带内或由该断裂带内向两侧延伸,这体现了沂沭断裂带一直是研究区内发震构造的主体。所有地震事件地层分布于该断裂带纵中轴线两侧150~180km以内的同沉积盆地,这证明该深大断裂带的两侧近区是强构造地震活动区。作者关于地震事件层位的时空分布的论述和图解,展示了该断裂带自形成以来的地震作用的过程与历史,清晰地勾绘出了这条长期活动地震带的影响范围,这不仅对分析此类深大活动断裂带及其附近由地震引发的软沉积物变形与地震作用具有重要意义,而且对评价此类地震带对地表和建筑物的地震破坏效应也具有重要意义。 展开更多
关键词 沂沭断裂带 地震事件地层 震积岩 震火山岩 时空分布
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研究动态黑洞温度的新乌龟坐标 被引量:10
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作者 赵峥 杨健 刘文彪 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第1期32-32,共1页
关键词 黑洞 乌龟坐标 事件视界 温度
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基于四次方程的三角解研究非球对称动态黑洞的“类视界面” 被引量:6
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作者 成谢锋 陶冶薇 +1 位作者 李传安 苏九清 《工程数学学报》 CSCD 北大核心 2002年第3期39-44,共6页
给出了具有实用价值的四次方程的三角解正根公式 ,并以匀加速直线运动的Kerr黑洞为例 ,成功的研究了非球对称动态黑洞的“类视界面”。
关键词 四次方程 三角解 非球对称动态黑洞 类视界面
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视界邻域的几何与黑洞熵 被引量:14
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作者 李翔 赵峥 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2000年第1期69-74,共6页
视界邻域的时空具有类似Rindler度规的几何结构 ,从这个背景下的场方程出发 ,利用brick wall方法分别计算了标量场和Dirac场的熵 ,很自然地得到熵与面积成正比的结果 .这一结果适用于一大类黑洞 .还讨论了极端黑洞熵 ,指出拓扑熵只有经... 视界邻域的时空具有类似Rindler度规的几何结构 ,从这个背景下的场方程出发 ,利用brick wall方法分别计算了标量场和Dirac场的熵 ,很自然地得到熵与面积成正比的结果 .这一结果适用于一大类黑洞 .还讨论了极端黑洞熵 ,指出拓扑熵只有经典意义而不是量子的观点 . 展开更多
关键词 Rindler度规 黑洞熵 几何结构 视界领域
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变加速直线运动带电黑洞的非热效应 被引量:5
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作者 孟庆苗 苏九清 张冠芬 《河南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第2期54-57,共4页
利用弯曲时空中标量粒子运动的Hamilton-Jacobin方程,研究了变加速直线运动带电黑洞周围时空中的自发辐射.得到了自发辐射的能量条件,它不仅依赖于黑洞的质量、电荷和加速度,还与黑洞视界的变化有关,与黑洞视界附近的四维电磁势有关.
关键词 黑洞 视界 HAMILTON-JACOBIN方程 非热辐射
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黑洞熵公式的简单推导 被引量:5
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作者 李翔 赵峥 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2000年第2期193-194,共2页
Black hole is treated as 2 D membrane. Starting from the usual state equation of thermal radiation, the black hole entropy is technically computed, and the result that is proportional to the area of horizon is briefly... Black hole is treated as 2 D membrane. Starting from the usual state equation of thermal radiation, the black hole entropy is technically computed, and the result that is proportional to the area of horizon is briefly obtained. 展开更多
关键词 黑洞熵 视界 内禀性质 熵密度 辐射体系
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一个静态Gutsunaev-Manko黑洞视界温度的计算方法 被引量:4
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作者 杨树政 陶才德 唐廷载 《数学物理学报(A辑)》 CSCD 北大核心 1998年第1期1-5,共5页
计算出了一个新的静态Gutsunaev-Manko黑洞的视界温度,其结果表明,此黑洞存在热辐射,除了内禀奇点所在处之外,视界温度是常数,黑洞质量多极矩的存在将对内禀奇点处的视界温度产生很大影响.
关键词 黑洞 内禀奇点 视界温度
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动态Dilaton-Maxwell时空中Dirac场的熵 被引量:2
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作者 宋太平 侯晨霞 赵峥 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第3期256-260,共5页
从求解Dilaton-Maxwell时空中Dirac粒子所遵从的动力学方程出发,计算出该时空中Dirac场的熵,得到了熵与视界的面积成正比的结论.
关键词 黑洞 DIRAC方程 视界
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由Dirac方程研究Kerr-Newman黑洞的新方法 被引量:3
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作者 孟庆苗 张建华 李传安 《新疆大学学报(自然科学版)》 CAS 1995年第2期56-61,共6页
本文用新的方法研究了Kerr-Newman黑洞的热辐射,从Dirac四分量旋量方程出发,经广义Tortoise坐标变换,直接导出Kerr-Newman黑洞的视界位置及温度函数,并最终获得了Dirac粒子的热谱公式.
关键词 零标架 狄拉克方程 视界 K-N黑洞 黑洞
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确定事件视界的新公式 被引量:3
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作者 赵峥 刘辽 《北京师范大学学报(自然科学版)》 CAS CSCD 1991年第2期209-210,共2页
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关键词 事件视界 视界 黑洞 稳态时空
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动态时空中事件视界的确定 被引量:5
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作者 黎忠恒 米丽琴 《宁夏大学学报(自然科学版)》 CAS 1998年第3期238-240,共3页
在一般球对称与平面对称动态时空中讨论了York方法和零曲面方法,证明了用零曲面确定事件视界是一种行之有效的方法,并给出了Vaidya-Bonnerdesiter事件视界的一组有用的近似值.
关键词 零曲面 动态时空 事件视界 黑洞
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