简述狭义相对论时空观

从光速不变原理出发,讨论相对行驶的两列长度相等的列车上的两个基本的时空测量实验,通过启发武的方法,用通俗的语言定性介绍狭义相对论时空观．     

狭义相对论中的质量、能量与对称性

爱因斯坦狭义相对论引起物理学基本原理和基本概念的巨大变革。如果要列举除了相对性原理和光速不变原理之外最重要的变革,同时性的相对性、关于质量与能量的概念及其内在联系,应是首选。     

谈狭义相对论时空理论教学——大学物理课程讲授狭义相对论之我见

依据狭义相对论基本原理和物理事例,导出钟慢、尺缩效应和同时相对性,再以此为据导出洛伦兹变换.     

狭义相对论学习中学生的错误理解研究概述

狭义相对论作为经典物理与近代物理的分水岭,对学生认识科学本质具有深远的影响.然而实际教学与研究显示,学生对狭义相对论存在许多错误理解.为了解决这一问题,本文梳理了国内外关于狭义相对论学习的相关研究.根据狭义相对论的知识框架,总结了学生在狭义相对论学习中普遍存在的错误理解,并分析其背后的原因,以期为未来狭义相对论的教学与研究提供借鉴.     

相对论问答录之一

<正>问题一、狭义相对论建立在哪两条公理的基础之上?狭义相对论建立在\"相对性原理\"和\"光速不变原理\"这两条公理的基础之上。相对性原理是说,物理规律在所有惯性系中都相同。需要强调,这里所说的相对性原理已经是伽利略相对性原理的推广。伽利略相对性原理只针对     

《相对论、宇宙与时空》连载③——爱因斯坦与狭义相对论(下)

7 突破绝对时空观 正当洛伦兹等人忙于研究相对于绝对空间运动的原子,在运动方向上发生收缩时,其内部结构会如何变化,内部的电荷分布会如何改变,内部的作用力会呈现何种状态的时候,爱因斯坦发表了他的相对论(狭义相对论).     

用时空代数推导狭义相对论的任意方向加速度变换

时空代数(Space-time Algebra,STA)是定义在4维实Minkowski矢量空间M~4上的16维几何代数(Geometric Algebra,也称为Clifford代数)Cl_(1,3),是一个可结合的代数环,它提供了不依赖于特定标架描述四维时空的方法.本文采用时空代数,给出推导狭义相对论中沿任意方向作相对运动的惯性系之间加速度变换的一种简单方法.     

狭义相对论中事件概念的教学

论述了事件概念的含义及准确理解事件在洛伦兹变换和相对论时空理论（运动时钟延缓、运动尺寸缩短等）教学中的作用．     

高维de Sitter时空中宇宙视界处的Fermi子隧穿

运用半经典近似理论,本文研究了来自静态高维de Sitter时空和高维Schwarzschild-de Sitter时空宇宙视界处的Fermi子隧穿辐射.在文中,描述1/2自旋粒子行为的Dirac方程被简化为一个简单的形式,接着运用方程组有非平凡解的条件,可以得到了半经典的Hamilton-Jacobi方程,从而使得问题大大得以简化,最终得到了静态de Sitter时空中宇宙视界处的Fermi子隧穿率和Hawking温度.     

On attempts to rescue the conventionality thesis of distant simultaneity in str

Recently, some conventionalists have tried to rescue the conventionality of distant simultaneity by introducing a spatially dependent (x,y,z), where {1,2,3}. In this paper, we show that this attempt fails by providing a detailed analysis of the coordinate independent and non-conventional procedure for directly measuring the metricd _M ² on eventspace with respect to a physical radar coordinate system. The measuredd _M ² in turn provides the empirical basis for uniquely determining the hyperplanes of space for a given inertial observer in a way that makes absolutely no reference whatsoever to any kind of synchrony, whether spatially dependent or not except for the sole purpose of assigning physical coordinates to events.     

From De Sitter Special Relativity and Snyder＇s Model to Complete Yang Model

The de Sitter special relativity on the Beltrami-de Sitter-spacetime and Snyder＇s model in the momentum space can be combined together with an IR-UV duality to get the complete Yang model at both classical and quantum levels, which are related by the proposed Killing quantization. It is actually a special relativity based on the principle of relativity of three universal constants （c, ρp, R）.     

华罗庚与爱因斯坦相对论及其扩展——纪念华罗庚诞辰一百周年

华罗庚先生运用矩阵几何与投影几何,研究并简化了爱因斯坦狭义相对论的基本原理,得到惯性运动的对称性,并促进了对德西特不变的狭义相对论的研究.他的深入考察至今仍引领着我们如何面对精确宇宙学的挑战.爱因斯坦相对论作为以宇宙常数Λ>0为特征的宇观物理学的基础面临疑难.相对性原理应该扩充到具有两个不变普适常数c和l,具有24个生成元的惯性运动对称性的相对性原理.于是,存在庞加莱、德西特和反德西特不变的3种相对论,伴随着对偶庞加莱运动学,它们构成相对论三位一体.取……,德西特相对论提供宇观尺度之新运动学,亦可避开相对性的宇宙佯谬.华老不仅是大数学家,而且是大思想家和大教育家,是一位为复兴中华民族而奉献终身的伟大代表.     

狭义相对论的欧氏假定与暗宇宙的启示

本文分析爱因斯坦相对论中关于一类没有相对运动的惯性系中刚性量杆的欧氏假定，以及相对性原理与宇宙学问的不协调。简单介绍我国学者提出的德西特不变的相对论，以及由暗宇宙启示的马赫原理。该相对论提供一个加速膨胀的观测宇宙所渐近趋向的模型。这里，不存在相对性原理与宇宙学问的不协调，存在一类相对于宇宙背景静止的优越惯性系，3维宇宙空间是闭的，宇宙常数起到惯性运动起源的作用。同时，这个模型提供观测宇宙的熵界，与全息原理的猜测一致，当曲率半径趋于无限时，这类优越惯性系仍然存在，不完全是爱因斯坦狭义相对论。     

Analytical Solutions of the Gravitational Field Equations in de Sitter and Anti-de Sitter Spacetimes

The generalized Laplace partial differential equation, describing gravitational fields, is investigated in de Sitter spacetime from several metric approaches—such as the Riemann, Beltrami, Börner-Dürr, and Prasad metrics—and analytical solutions of the derived Riccati radial differential equations are explicitly obtained. All angular differential equations trivially have solutions given by the spherical harmonics and all radial differential equations can be written as Riccati ordinary differential equations, which analytical solutions involve hypergeometric and Bessel functions. In particular, the radial differential equations predict the behavior of the gravitational field in de Sitter and anti-de Sitter spacetimes, and can shed new light on the investigations of quasinormal modes of perturbations of electromagnetic and gravitational fields in black hole neighborhood. The discussion concerning the geometry of de Sitter and anti-de Sitter spacetimes is not complete without mentioning how the wave equation behaves on such a background. It will prove convenient to begin with a discussion of the Laplace equation on hyperbolic space, partly since this is of interest in itself and also because the wave equation can be investigated by means of an analytic continuation from the hyperbolic space. We also solve the Laplace equation associated to the Prasad metric. After introducing the so called internal and external spaces—corresponding to the symmetry groups SO(3,2) and SO(4,1) respectively—we show that both radial differential equations can be led to Riccati ordinary differential equations, which solutions are given in terms of associated Legendre functions. For the Prasad metric with the radius of the universe independent of the parametrization, the internal and external metrics are shown to be of AdS-Schwarzschild-like type, and also the radial field equations arising are shown to be equivalent to Riccati equations whose solutions can be written in terms of generalized Laguerre polynomials and hypergeometric confluent functions.     

Noninertial Observers in Special Relativity and Clock Synchronization Debates

Selleri's arguments that a consideration of noninertial reference frames in the framework of special relativity identify “absolute simultaneity” as being “Nature's choice of synchronization” are considered. In the case of rectilinearly accelerating rockets, it is argued by considering two rockets which maintain a fixed proper separation rather than a fixed separation relative to the inertial frame in which they start from rest, that what seems the most “natural” choice for a simultaneity convention is problem-dependent and that Einstein's definition is the most “natural” (though still conventional) choice in this case. In addition, the supposed problems special relativity has with treating a rotating disk, namely how a pulse of light traveling around the circumference of the disk can have a local speed of light equal to c everywhere but a global speed not equal to c, and how coordinate transformations to the disk can give the Lorentz transformations in the limit of large disk radius but small angular velocity, are addressed. It is shown that the theory of Fermi frames solves both of these problems. It is also argued that the question of defining simultaneity relative to a uniformly rotating disk does not need to be resolved in order to resolve Ehrenfest's paradox.     

Spatial measures in special relativity do not empirically determine simultaneity relations: A reply to Coleman and Korté

Coleman and Korté have restated and defended an earlier attempt to refute the traditional thesis of the conventionality of simultaneity within special relativity. Here we argue their attempt still fails and respond to criticisms of a paper in which we addressed the inadequacies of their earlier paper. The spatial criterion they use to argue for standard synchronization throughout an inertial frame is merely a definition and provides no demonstration that a unique distant simultaneity relation exists in nature.