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从漂移速度到相对论时空变换 被引量:1
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作者 吴从军 《物理》 北大核心 2025年第2期128-133,共6页
文章提供了一种基于基础电磁学来引入狭义相对论的方法,无需借助麦克斯韦方程组。通过研究电荷和磁单极在正交电磁场中的漂移速度,可以得出“物理”的漂移速度存在一个普适的上限(即光速)。这样光速不变性及其不可超越性,就成为相对性... 文章提供了一种基于基础电磁学来引入狭义相对论的方法,无需借助麦克斯韦方程组。通过研究电荷和磁单极在正交电磁场中的漂移速度,可以得出“物理”的漂移速度存在一个普适的上限(即光速)。这样光速不变性及其不可超越性,就成为相对性原理的推论。 展开更多
关键词 麦克斯韦方程组 相对性原理 狭义相对论 正交电磁场 光速不变性 磁单极 漂移速度 电磁学
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空间引力波探测器中的锁臂控制器设计
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作者 张祎 李明哲 +3 位作者 王童 沈玉霖 杨杰 辛明 《光子学报》 北大核心 2025年第2期71-84,共14页
由于引力波信号非常微弱,需要对引力波探测器中激光系统的频率噪声及强度噪声等进行抑制才能满足引力波探测要求,激光锁臂则是抑制激光频率噪声的关键技术之一。将逆向设计思想引入到激光锁臂控制器的优化设计中,具体采用分层式结构,利... 由于引力波信号非常微弱,需要对引力波探测器中激光系统的频率噪声及强度噪声等进行抑制才能满足引力波探测要求,激光锁臂则是抑制激光频率噪声的关键技术之一。将逆向设计思想引入到激光锁臂控制器的优化设计中,具体采用分层式结构,利用多参数协同优化方式,对科学频段内(0.1 mHz~1 Hz)不同频率处的激光频率噪声抑制比进行协同优化。理论建模分析结果表明:优化后的控制器不仅可以提升激光频率噪声抑制效果,还能大幅度提高引力波信号相对于激光频率噪声及其他技术噪声的信噪比。相关研究成果可推广应用到其他架构的噪声耦合锁臂控制器的优化设计中。 展开更多
关键词 引力波探测 锁臂 激光频率噪声抑制 逆向设计 反馈控制
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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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The Relationship between Gravitational Acceleration and the Velocity of Light
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作者 Jiang Jian-zhong Zhang Xiang-qian 《Journal of Environmental Science and Engineering(A)》 2025年第5期238-244,共7页
Based on the mass-energy equation of special relativity and the assumption of the helical motion of light speed in cosmic space,we have theoretically demonstrated the true implications of Planck’s physical quantities... Based on the mass-energy equation of special relativity and the assumption of the helical motion of light speed in cosmic space,we have theoretically demonstrated the true implications of Planck’s physical quantities:Planck length and time represent the step size and period of the helical motion of light speed in the earliest cosmic space following the Big Bang;Planck energy constitutes the minimum energy unit associated with this spatial helical motion;Planck mass is the mass derived from this minimum energy unit.In accordance with the expression of Planck time,we have derived the relationship formula between gravitational acceleration and the speed of light,thereby uncovering an inevitable intrinsic connection between the gravitational field and the electromagnetic field,and indicating that the four fundamental forces in the universe can be unified.Finally,through our spatial helical motion model,we computed the specific values of the four fundamental forces at the moment of strong nuclear force separation.The results reveal that they are in complete agreement with the theoretical calculation values or experimental values in modern physics and quantum mechanics,thereby providing an interesting hint for the unified field theories. 展开更多
关键词 Gravitational acceleration light-speed helical motion of space Planck time unified field theory the Big Bang
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Unstable regions of anisotropic relativistic spheres in higher dimensions
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作者 M Yousaf Bander Almutairi +2 位作者 M Z Bhatti Z Yousaf A S Khan 《Communications in Theoretical Physics》 2025年第3期112-129,共18页
In this work,we consider the collapse of a D-dimensional sphere in the framework of a higher-dimensional spherically symmetric space-time in which the gravitational action chosen is claimed to be somehow linked to the... In this work,we consider the collapse of a D-dimensional sphere in the framework of a higher-dimensional spherically symmetric space-time in which the gravitational action chosen is claimed to be somehow linked to the D-dimensional modified term.This work investigates the criteria for the dynamical instability of anisotropic relativistic sphere systems with D-dimensional modified gravity.The certain conditions are applied that lead to the collapse equation and their effects on adiabatic indexΓin both Newtonian(N)and Post-Newtonian(PN)regimes by using a perturbation scheme.The study explores that theΓplays a crucial role in determining the degree of dynamical instability.This index characterizes the fluid's stiffness and has a significant impact on defining the ranges of instability.This systematic investigation demonstrates the influence of various material properties such as anisotropic pressure,kinematic quantities,mass function,D-dimensional modified gravity parameters,and the radial profile of energy density on the instability of considered structures during their evolution.This work also displays the dynamical behavior of spherically symmetric fluid configuration via graphical approaches. 展开更多
关键词 GRAVITATION dynamical instability mathematical and relativistic aspects of cosmology mathematical physics
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新量子理论描述引力的方式与标准模型一致
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作者 张梦然 《电子产品可靠性与环境试验》 2025年第3期125-125,共1页
长期以来,物理学家一直在努力调和现代物理学的两大支柱——量子场论和爱因斯坦广义相对论之间的不兼容性。如今,芬兰阿尔托大学研究人员提出了一种新的量子引力理论,它描述引力的方式与粒子物理学标准模型一致,为深入理解宇宙起源打开... 长期以来,物理学家一直在努力调和现代物理学的两大支柱——量子场论和爱因斯坦广义相对论之间的不兼容性。如今,芬兰阿尔托大学研究人员提出了一种新的量子引力理论,它描述引力的方式与粒子物理学标准模型一致,为深入理解宇宙起源打开了思路。相关研究发表在最新一期《物理学进展报告》上。 展开更多
关键词 量子引力 标准模型 量子场论 广义相对论
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近极端Dilaton黑洞的弱宇宙监督假设探讨
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作者 唐浩 《渭南师范学院学报》 2025年第5期88-93,共6页
由Penrose提出的弱宇宙监督假设认为宇宙中不可能出现裸奇点,否则物理中的因果性将丧失。尽管目前仍未观测到裸奇点,但该假设也并未被完全证明。文章针对近极端Dilaton黑洞讨论其是否可能存在裸奇点。使用Wald等提出的计算方法,引入合... 由Penrose提出的弱宇宙监督假设认为宇宙中不可能出现裸奇点,否则物理中的因果性将丧失。尽管目前仍未观测到裸奇点,但该假设也并未被完全证明。文章针对近极端Dilaton黑洞讨论其是否可能存在裸奇点。使用Wald等提出的计算方法,引入合适的试探粒子并使黑洞吸入该粒子,有可能会导致其视界消失,从而出现裸奇点。能否找到合适的试探粒子是黑洞是否出现裸奇点的关键,从而检验弱宇宙监督假设。计算结果表明,无法找到任何试探粒子使得近极端Dilaton黑洞出现裸奇点,支持了弱宇宙监督假设。 展开更多
关键词 弱宇宙监督假设 奇点 视界 近极端黑洞
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Remarks on“Casimir wormholes inspired by electric charge in Einstein–Gauss–Bonnet gravity”
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作者 M S Cunha M O Tahim C R Muniz 《Communications in Theoretical Physics》 2025年第8期113-116,共4页
This work revisits the analysis of charged Casimir wormhole solutions within the framework of Einstein–Gauss–Bonnet(EGB)gravity,addressing a critical inconsistency in the approach presented by Farooq et al.Specifica... This work revisits the analysis of charged Casimir wormhole solutions within the framework of Einstein–Gauss–Bonnet(EGB)gravity,addressing a critical inconsistency in the approach presented by Farooq et al.Specifically,we show that their use of four-dimensional Casimir and electric field energy densities are incompatible with the higher-dimensional nature of EGB gravity,which requires D≥5.We provide the correct formulation for the energy densities and revise the wormhole properties under this framework,offering a refined perspective on the interplay between extra dimensions and Casimir effects in EGB gravity. 展开更多
关键词 Einstein-Gauss-Bonnet CASIMIR WORMHOLE higher dimensional
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具有磁矩和磁荷的静态中子星引力透镜效应
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作者 张软静 司峻文 +2 位作者 刘在旭 陈文斌 王振宇 《南阳师范学院学报》 2025年第3期28-34,共7页
研究了具有磁矩和磁荷的静态中子星的引力透镜效应。借助测地线方程,推导出了光子在中子星时空背景下的光球半径,该半径随着磁荷的增加而逐渐减小。在探究引力透镜偏转角的过程中发现:偏转角随着磁荷的增大而增大,而随着磁矩的增大而减... 研究了具有磁矩和磁荷的静态中子星的引力透镜效应。借助测地线方程,推导出了光子在中子星时空背景下的光球半径,该半径随着磁荷的增加而逐渐减小。在探究引力透镜偏转角的过程中发现:偏转角随着磁荷的增大而增大,而随着磁矩的增大而减小。当磁荷取0.5时,偏转角为定值,与磁矩无关;而当磁荷和磁矩均趋近于0时,所有参数都会回归到Schwarzschild情况。利用实际观测到的中子星数据,深入分析了透镜体可观测量对偏转角的影响。研究结果显示,中子星的质量越大,观测者的距离越近,质距比越大,偏转角就越大。 展开更多
关键词 引力透镜 中子星 磁矩 磁荷
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Rastall引力中的Kantowski-Sachs宇宙
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作者 付林圣 奚萍 《上海师范大学学报(自然科学版中英文)》 2025年第3期277-282,共6页
本文主要研究了Rastall引力理论中Kantowski-Sachs宇宙的尺度因子中的各向异性因子δ(t)的演化行为.研究结果表明,当Rastall参数各向异性时,Kantowski-Sachs宇宙的各向异性因子δ(t)随着时间增加而减小,且当时间足够长时趋于零,即Kantow... 本文主要研究了Rastall引力理论中Kantowski-Sachs宇宙的尺度因子中的各向异性因子δ(t)的演化行为.研究结果表明,当Rastall参数各向异性时,Kantowski-Sachs宇宙的各向异性因子δ(t)随着时间增加而减小,且当时间足够长时趋于零,即Kantowski-Sachs宇宙可以演化成一个各向同性的、闭合的、稳定的宇宙.此外,这个模型中的β参量(即Rastall参数λ和λ_(1)的差)会影响各向异性因子δ的大小. 展开更多
关键词 Rastall引力 Rastall参数 Kantowski-Sachs宇宙 各向异性因子δ(t)
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Relativistic hyperpolarizabilities of atomic H,Li,and Be^(+)systems
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作者 Shan-Shan Lu Hong-Yuan Zheng +2 位作者 Zong-Chao Yan James F.Babb Li-Yan Tang 《Chinese Physics B》 2025年第2期230-239,共10页
For atoms in external electric fields,the hyperpolarizabilities are the coefficients describing the nonlinear interactions contributing to the induced energies at the fourth power of the applied electric fields.Accura... For atoms in external electric fields,the hyperpolarizabilities are the coefficients describing the nonlinear interactions contributing to the induced energies at the fourth power of the applied electric fields.Accurate evaluations of these coefficients for various systems are crucial for improving precision in advanced atom-based optical lattice clocks and for estimating field-induced effects in atoms for quantum information applications.However,there is a notable scarcity of research on atomic hyperpolarizabilities,especially in the relativistic realm.Our work addresses this gap by establishing a novel set of alternative formulas for the hyperpolarizability based on the fourth-order perturbation theory.These formulas offer a more reasonable regrouping of scalar and tensor components compared to previous formulas,thereby enhancing their correctness and applicability.To validate our formulas,we perform the calculations for the ground and low-lying excited pure states of few-electron atoms H,Li,and Be^(+).The highly accurate results obtained for the H atom could serve as benchmarks for further development of other theoretical methods. 展开更多
关键词 HYPERPOLARIZABILITIES Stark effect fourth-order perturbation few-electron atoms
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Relativistic model for anisotropic compact stars in embedding class-Ⅰspacetime
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作者 Susmita Sarkar Moumita Sarkar +1 位作者 Nayan Sarkar Farook Rahaman 《Communications in Theoretical Physics》 2025年第1期143-157,共15页
In the present article,we introduce a completely new regular model for static,spherically symmetric celestial fluid spheres in embedding classⅠspacetime.In this regard,needfully,we propose a new suitable metric poten... In the present article,we introduce a completely new regular model for static,spherically symmetric celestial fluid spheres in embedding classⅠspacetime.In this regard,needfully,we propose a new suitable metric potential e^(λ(r))to generate the present model.The various analyses on energy density,pressure,anisotropic factor,mass,compactness parameter,redshift,and energy condition make sure the model is physically viable on the ground of model stars Vela X-1,Cen X-3,SMC X-4,and LMC X-4.The reported solutions also respect the equilibrium state by satisfying the Tolman-Oppenheimer-Volkoff(TOV)equation and ensure stability by satisfying the causality condition,condition on the adiabatic index,and Harrison-Zeldovich-Novikov condition.The generated M-R graph matches the ranges of masses and radii for the model compact stars.Additionally,this study provides estimates of the moment of inertia based on the I-M graph. 展开更多
关键词 general relativity compact star ANISOTROPY Karmarkar condition
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基于改进的薄膜模型法计算Vaidya黑洞的熵
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作者 张丹丹 《渭南师范学院学报》 2025年第11期87-93,共7页
黑洞熵的起源问题是黑洞热力学中的重要问题。旧的薄膜模型中的厚度因子因为可以无限趋近于0,可能会导致半经典条件失效,且为了得到霍金熵的形式必须人为地选取截断因子,缺少了一定的物理意义。在引入广义不确定关系给出的最小尺度对薄... 黑洞熵的起源问题是黑洞热力学中的重要问题。旧的薄膜模型中的厚度因子因为可以无限趋近于0,可能会导致半经典条件失效,且为了得到霍金熵的形式必须人为地选取截断因子,缺少了一定的物理意义。在引入广义不确定关系给出的最小尺度对薄膜模型的厚度因子进行改进后,重新对动态Vaidya黑洞的事件视界熵进行了讨论,不仅得到了与旧有薄膜模型类似的结果,而且能给出更具物理意义的自然截断因子。 展开更多
关键词 黑洞熵 薄膜模型 VAIDYA黑洞 广义不确定关系
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Retrieval of energy-momentum tensor for self-gravitating and collapsing thin spherical shell
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作者 Wenbin Lin 《Communications in Theoretical Physics》 2025年第7期171-173,共3页
We prove that the post-Newtonian time-dependent metric of the self-gravitating and collapsing infinitely-thin spherical shell does satisfy Einstein field equations to the corresponding order.Meanwhile, the leading-ord... We prove that the post-Newtonian time-dependent metric of the self-gravitating and collapsing infinitely-thin spherical shell does satisfy Einstein field equations to the corresponding order.Meanwhile, the leading-order components of the thin spherical shell's energy-momentum tensor are recovered. 展开更多
关键词 post-Newtonian approximation gravitomagnetic field second gravitational potential spherically-symmetric system
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Plasma impact on black hole shadows and gravitational weak lensing in the Einstein-Maxwell-scalar theory
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作者 Mirzabek Alloqulov Sanjar Shaymatov +1 位作者 Abdul Jawad Oripjon Zaripov 《Communications in Theoretical Physics》 2025年第1期130-142,共13页
In this paper,we investigate the optical properties of a non-rotating charged black hole(BH)in the Einstein-Maxwell-scalar(EMS)theory,together with a plasma medium.We first consider the photon sphere and shadow radius... In this paper,we investigate the optical properties of a non-rotating charged black hole(BH)in the Einstein-Maxwell-scalar(EMS)theory,together with a plasma medium.We first consider the photon sphere and shadow radius under the impact of the plasma medium existing in the environment surrounding the BH in the EMS theory.We show that the radius of the photon sphere and the BH shadow decrease under the influence of the parameterβ.We further study gravitational weak lensing in detail by adapting general methods and derive the light ray's deflection angle around the BH together with the plasma environment.It is found that for uniform plasma,the deflection angle increases with the rise of the plasma parameter,whereas it decreases with the increase of the plasma parameter for non-uniform plasma.Besides,we also study the magnification of image brightness. 展开更多
关键词 general relativity black hole shadow gravitational weak lensing
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Dynamical system approach of interacting dark energy models in f(R,T^(φ))gravity
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作者 Amit Samaddar S Surendra Singh +1 位作者 Shah Muhammad Euaggelos E Zotos 《Communications in Theoretical Physics》 2025年第4期117-128,共12页
We have examined an isotropic and homogeneous cosmological model in f(R,T^(φ))gravity,where R represents the Ricci scalar and T^(φ)exhibits the energy momentum tensor's trace.We examine the stability criteria by... We have examined an isotropic and homogeneous cosmological model in f(R,T^(φ))gravity,where R represents the Ricci scalar and T^(φ)exhibits the energy momentum tensor's trace.We examine the stability criteria by performing the dynamical system analysis for our model f(R,T^(φ))=R+2(a T^(φ)+b),where a and b are the constants.We derive a set of autonomous equations and find their solutions by assuming a flat potential V0.We assess the equilibrium points from these equations and find the eigenvalues.We analyze the physical interpretation of the phase space for this system.We obtain three stable equilibrium points.We also examine the interaction between the scalar field and dark energy,represented by Q=ψH_(ρde)and determine the equilibrium points for this interaction.We identify four stable equilibrium points for this interaction.We calculate the values of the physical parameters for both scenarios at each equilibrium point,indicating the Universe's accelerated expansion. 展开更多
关键词 f(R T^(φ))gravity field equations phase space analysis interaction
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爱因斯坦的创意宇宙
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作者 方在庆(译) +1 位作者 何钧(译) 雷煜(译) 《科学画报》 2025年第4期44-45,共2页
阿尔伯特·爱因斯坦最出名的形象,可能是那个发明相对论、有着银丝头发的古怪物理学家,但相对论只是这位天才对人类知识和现代科学所作贡献的一个方面。阿尔伯特·爱因斯坦于1879年3月14日出生在德国南部的乌尔姆。他的叔叔和... 阿尔伯特·爱因斯坦最出名的形象,可能是那个发明相对论、有着银丝头发的古怪物理学家,但相对论只是这位天才对人类知识和现代科学所作贡献的一个方面。阿尔伯特·爱因斯坦于1879年3月14日出生在德国南部的乌尔姆。他的叔叔和父亲拥有一家生产电工设备的公司。父亲赫尔曼是业务经理,叔叔雅各布是专业工程师。 展开更多
关键词 爱因斯坦 相对论 物理学家
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On the transverse-traceless gauge condition when matter is presented
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作者 Yadong Xue Xiaokai He Zhoujian Cao 《Communications in Theoretical Physics》 2025年第3期94-100,共7页
The transverse-traceless gauge condition is an important concept in the theory of gravitational waves.It is well known that a vacuum is one of the key conditions to guarantee the existence of the transverse-traceless ... The transverse-traceless gauge condition is an important concept in the theory of gravitational waves.It is well known that a vacuum is one of the key conditions to guarantee the existence of the transverse-traceless gauge.Although it is thin,the interstellar medium is ubiquitous in the Universe.Therefore,it is important to understand the concept of gravitational waves when matter is presented.Bondi-Metzner-Sachs theory has solved the gauge problem related to gravitational waves.But it does not help with cases when the gravitational wave propagates in matter.This paper discusses possible extensions of the transverse-traceless gauge condition to Minkowski perturbation with matter presented. 展开更多
关键词 gravitational wave transverse-traceless gauge condition
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一种特定的狭义相对论效应首次得到实验验证
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作者 松云 《科学》 2025年第3期44-44,共1页
[本刊讯]由维也纳工业大学领衔的合作团队利用皮秒激光脉冲和超高速相机首次为狭义相对论的一个推论:特雷尔-彭罗斯效应提供了可视化证明。相关成果于2025年4月30日发表在《通信物理学》(Communications Physics)上。
关键词 狭义相对论 特雷尔-彭罗斯效应
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狭义相对论时空观的图像解译 被引量:1
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作者 缪劲松 胡海云 《物理与工程》 2024年第3期22-27,共6页
狭义相对论的时空观之所以抽象且难以理解,一方面是因为狭义相对论所涉及的时空效应,如同时性的相对性、长度收缩和时间延缓等,在实际中都很难被观测到;另一方面是因为我们很难将这些时空效应同时直观形象地描述出来,并且给出不同参考... 狭义相对论的时空观之所以抽象且难以理解,一方面是因为狭义相对论所涉及的时空效应,如同时性的相对性、长度收缩和时间延缓等,在实际中都很难被观测到;另一方面是因为我们很难将这些时空效应同时直观形象地描述出来,并且给出不同参考系各自观测到的时空效应之间的对应关系。本文针对这一问题,利用图示法将两个参考系在不同时刻观测到的时空图像表示出来,并结合具体数值对他们间的对应关系进行讨论。在图示法中同时考虑了同时性的相对性、长度收缩和时间延缓这三个狭义相对论重要的时空效应,这样可直观形象地看到在一个参考系中得到的观测结果会被另一个参考系所认同,正是这些彼此认同的观测结果构成了狭义相对论的时空观。通过对不同参考系中观察到的时空图像及其相互联系的讨论,可以加深学生对狭义相对论时空效应及洛伦兹变换的物理意义的理解。 展开更多
关键词 狭义相对论 时间延缓 长度收缩 同时性的相对性 洛伦兹变换 时空图像
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