神马作文网广义相对论 英语版.老师留的作业,要求英语版与中文版的.中文版我已经找到了,是谷锐译翻译的《广义相对论 一个极其不可思议
来源：学生作业帮 编辑：神马作文网作业帮 分类：英语作业 时间：2024/11/11 19:28:10
广义相对论 英语版.
老师留的作业,要求英语版与中文版的.中文版我已经找到了,是
谷锐译翻译的《广义相对论 一个极其不可思议的世界》可是找不到对应的英语版啊.
不是我看的.这是个作业.
老师留的作业,要求英语版与中文版的.中文版我已经找到了,是
谷锐译翻译的《广义相对论 一个极其不可思议的世界》可是找不到对应的英语版啊.
不是我看的.这是个作业.
维基的相对论简介,如果嫌不够深,多给分我给你更深的版本
Theory of relativity
From Wikipedia, the free encyclopedia
Jump to: navigation, search
This article is about the scientific concept. For philosophical or sociological theories about relativity, see Relativism. For the silent film, see The Einstein Theory of Relativity.
Two-dimensional projection of a three-dimensional analogy of space-time curvature described in General Relativity.The theory of relativity, or simply relativity, encompasses two theories of Albert Einstein: special relativity and general relativity.[1] However, the word "relativity" is sometimes used in reference to Galilean invariance.
The term "theory of relativity" was based on the expression "relative theory" (German: Relativtheorie) used by Max Planck in 1906, who emphasized how the theory uses the principle of relativity. In the discussion section of the same paper Alfred Bucherer used for the first time the expression "theory of relativity" (German: Relativitätstheorie).[2][3]
Contents [hide]
1 Scope
1.1 Two theory view
2 Special relativity
3 General relativity
4 See also
5 References
6 Further reading
7 External links
[edit] Scope
The theory of relativity enriched physics and astronomy during the 20th century. When first published, relativity superseded a 200-year-old theory of mechanics elucidated by Isaac Newton. It changed perceptions.[4][5][6]
For example, it overturned the concept of motion from Newton's day, into all motion is relative. Time was no longer uniform and absolute, as related to everyday experience. Furthermore, no longer could physics be understood as space by itself, and time by itself. Instead, an added dimension had to be taken into account with curved space-time. Time now depended on velocity, and contraction became a fundamental consequence at appropriate speeds.[4][5][6]
In the field of microscopic physics, relativity catalyzed and added an essential depth of knowledge to the science of elementary particles and their fundamental interactions, along with introducing the nuclear age. With relativity, cosmology and astrophysics predicted extraordinary astronomical phenomena such as neutron stars, black holes, and gravitational waves.[4][5][6]
[edit] Two theory view
The theory of relativity was representative of more than a single new physical theory. It affected the theories and methodologies across all the physical sciences. However, as stated above, this is more likely perceived as two separate theories. There are some related explanations for this. First, special relativity was published in 1905, and the final form of general relativity was published in 1916.[4]
Second, special relativity fits with and solves for elementary particles and their interactions, whereas general relativity solves for the cosmological and astrophysical realm (including astronomy).[4]
Third, special relativity was widely accepted in the physics community by 1920. This theory rapidly became a notable and necessary tool for theorists and experimentalists in the new fields of atomic physics, nuclear physics, and quantum mechanics. Conversely, general relativity did not appear to be as useful. There had appeared to be little applicability for experimentalists as most applications were for astronomical scales. It seemed limited to only making minor corrections to predictions of Newtonian gravitation theory. Its impact was not apparent until the 1930s.[4]
Finally, the mathematics of general relativity appeared to be incomprehensibly dense. Consequently, only a small number of people in the world, at that time, could fully understand the theory in detail. This remained the case for the next 40 years. Then, at around 1960 a critical resurgence in interest occurred which has resulted in making general relativity central to physics and astronomy. New mathematical techniques applicable to the study of general relativity substantially streamlined calculations. From this, physically discernible concepts were isolated from the mathematical complexity. Also, the discovery of exotic astronomical phenomena in which general relativity was crucially relevant, helped to catalyze this resurgence. The astronomical phenomena included quasars (1963), the 3-kelvin microwave background radiation (1965), pulsars (1967), and the discovery of the first black hole candidates (1971).[4]
[edit] Special relativity
Main article: Special relativity
USSR stamp dedicated to Albert EinsteinSpecial relativity is a theory of the structure of spacetime. It was introduced in Albert Einstein's 1905 paper "On the Electrodynamics of Moving Bodies" (for the contributions of many other physicists see History of special relativity). Special relativity is based on two postulates which are contradictory in classical mechanics:
The laws of physics are the same for all observers in uniform motion relative to one another (principle of relativity),
The speed of light in a vacuum is the same for all observers, regardless of their relative motion or of the motion of the source of the light.
The resultant theory agrees with experiment better than classical mechanics, e.g. in the Michelson-Morley experiment that supports postulate 2, but also has many surprising consequences. Some of these are:
Relativity of simultaneity: Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
Time dilation: Moving clocks are measured to tick more slowly than an observer's "stationary" clock.
Length contraction: Objects are measured to be shortened in the direction that they are moving with respect to the observer.
Mass-energy equivalence: E = mc2, energy and mass are equivalent and transmutable.
Maximum speed is finite: No physical object or message or field line can travel faster than light.
The defining feature of special relativity is the replacement of the Galilean transformations of classical mechanics by the Lorentz transformations. (See Maxwell's equations of electromagnetism and introduction to special relativity).
[edit] General relativity
Main article: General relativity
General relativity is a theory of gravitation developed by Einstein in the years 1907–1915. The development of general relativity began with the equivalence principle, under which the states of accelerated motion and being at rest in a gravitational field (for example when standing on the surface of the Earth) are physically identical. The upshot of this is that free fall is inertial motion; an object in free fall is falling because that is how objects move when there is no force being exerted on them, instead of this being due to the force of gravity as is the case in classical mechanics. This is incompatible with classical mechanics and special relativity because in those theories inertially moving objects cannot accelerate with respect to each other, but objects in free fall do so. To resolve this difficulty Einstein first proposed that spacetime is curved. In 1915, he devised the Einstein field equations which relate the curvature of spacetime with the mass, energy, and momentum within it.
Some of the consequences of general relativity are:
Clocks run more slowly in regions of lower gravitational potential.[7] This is called gravitational time dilation.
Orbits precess in a way unexpected in Newton's theory of gravity. (This has been observed in the orbit of Mercury and in binary pulsars).
Rays of light bend in the presence of a gravitational field.
Rotating masses "drag along" the spacetime around them; a phenomenon termed "frame-dragging".
The Universe is expanding, and the far parts of it are moving away from us faster than the speed of light.
Technically, general relativity is a metric theory of gravitation whose defining feature is its use of the Einstein field equations. The solutions of the field equations are metric tensors which define the topology of the spacetime and how objects move inertially.
相对论
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E = mc2相对论是关于时空和引力的理论,主要由爱因斯坦创立,依其研究对象的不同可分为狭义相对论和广义相对论.相对论和量子力学的提出给物理学带来了革命性的变化,它们共同奠定了近代物理学的基础.相对论极大的改变了人类对宇宙和自然的“常识性”观念,提出了“同时的相对性”、“四维时空”、“弯曲时空”等全新的概念.不过近年来,人们对于物理理论的分类有了一种新的认识——以其理论是否是决定论的来划分经典与非经典的物理学,即“非经典的＝量子的”.在这个意义下,相对论仍然是一种经典的理论.
目录 [隐藏]
1 狭义与广义相对论的分野
2 狭义相对论
3 广义相对论
4 相对论的应用
5 相对论对物理学发展的影响
6 文化影响
7 注释
8 参见
9 外部链接
狭义与广义相对论的分野
传统上,在爱因斯坦刚刚提出相对论的初期,人们以所讨论的问题是否涉及非惯性参考系来作为狭义与广义相对论分类的标志.随着相对论理论的发展,这种分类方法越来越显出其缺点——参考系是跟观察者有关的,以这样一个相对的物理对象来划分物理理论,被认为较不能反映问题的本质.目前一般认为,狭义与广义相对论的区别在于所讨论的问题是否涉及引力（弯曲时空）,即狭义相对论只涉及那些没有引力作用或者引力作用可以忽略的问题,而广义相对论则是讨论有引力作用时的物理学的.用相对论的语言来说,就是狭义相对论的背景时空是平直的,即四维平凡流型配以闵氏度规,其曲率张量为零,又称闵氏时空；而广义相对论的背景时空则是弯曲的,其曲率张量不为零.
狭义相对论
主条目：狭义相对论
爱因斯坦在他1905年的论文《论动体的电动力学》中介绍了其狭义相对论.
狭义相对论建立在如下的两个基本公设上：
狭义相对性原理（狭义协变性原理）：一切的惯性参考系都是平权的,即物理规律的形式在任何的惯性参考系中是相同的.这意味着物理规律对于一位静止在实验室里的观察者和一个相对于实验室高速匀速运动着的电子是相同的.
光速不变原理：真空中的光速在任何参考系下是恒定不变的,这用几何语言可以表为光子在时空中的世界线总是类光的.也正是由于光子有这样的实验性质,在国际单位制中使用了“光在真空中1/2,9979,2458秒内所走过的距离”来定义长度单位“米”（米）.
在狭义相对论提出以前,人们认为时间和空间是各自独立的绝对的存在.而爱因斯坦的相对论首次提出了时空的概念,它认为时间和空间各自都不是绝对的,而绝对的是一个它们的整体——时空,在时空中运动的观者可以建立“自己的”参照系,可以定义“自己的”时间和空间（即对四维时空做“3＋1分解”）,而不同的观者所定义的时间和空间可以是不同的.具体的来说,在闵氏时空中,而如果一个惯性观者（G）相对于另一个惯性观者（G'）在做匀速运动,则他们所定义的时间（t与t'）和空间({x,y,z}与{x',y',z'})之间满足洛伦兹变换.而在这一变换关系下就可以推导出“尺缩”、“钟慢”等效应,具体见狭义相对论条目.
在爱因斯坦以前,人们广泛的关注于麦克斯韦方程组在伽利略变换下不协变的问题,也有人注意到过爱因斯坦提出狭义相对论所基于的实验（如光程差实验等）,也有人推导出过与爱因斯坦类似的数学表达式（如洛伦兹变换）,但只有爱因斯坦将这些因素与经典物理的时空观结合起来提出了狭义相对论,并极大的改变了我们的时空观.在这一点上,狭义相对论是革命性的.
广义相对论
主条目：广义相对论
在本质上,所有的物理学问题都涉及采用什么时空观的问题.在二十世纪以前的经典物理学里,人们采用的是牛顿的绝对时空观.而相对论的提出改变了这种时空观,这就导致人们必须依相对论的要求对经典物理学的公式进行改写,以使其具有相对论所要求的洛伦兹协变性而不是以往的伽利略协变性.在经典理论物理的三大领域中,电动力学本身就是洛伦兹协变的,无需改写；统计力学有一定的特殊性,但这一特殊性并不带来很多急需解决的原则上的困难；而经典力学的大部分都可以成功的改写为相对论形式,以使其可以用来更好的描述高速运动下的物体,但是唯独牛顿的引力理论无法在狭义相对论的框架体系下改写,这直接导致爱因斯坦扩展其狭义相对论,而得到了广义相对论.
爱因斯坦在1915年左右发表的一系列论文中给出了广义相对论最初的形式.他首先注意到了被称之为（弱）等效原理的实验事实：引力质量与惯性质量是相等的（目前实验证实,在10 − 12的精确度范围内,仍没有看到引力质量与惯性质量的差别）.这一事实也可以理解为,当除了引力之外不受其他力时,所有质量足够小（即其本身的质量对引力场的影响可以忽略）的测验物体在同一引力场中以同样的方式运动.既然如此,则不妨认为引力其实并不是一种“力”,而是一种时空效应,即物体的质量（准确的说应当为非零的能动张量）能够产生时空的弯曲,引力源对于测验物体的引力正是这种时空弯曲所造成的一种几何效应.这时,所有的测验物体就在这个弯曲的时空中做惯性运动,其运动轨迹正是该弯曲时空的测地线,它们都遵守测地线方程.正是在这样的思路下,爱因斯坦得到了其广义相对论.
系统的说,广义相对论包括如下几条基本假设[1].：
广义相对性原理（广义协变性原理）：任何物理规律都应该用与参考系无关的物理量表示出来.用几何语言描述即为,任何在物理规律中出现的时空量都应当为该时空的度规或者由其导出的物理量.
爱因斯坦场方程（详见广义相对论条目）：它具体表达了时空中的物质（能动张量）对于时空几何（曲率张量的函数）的影响,其中对应能动张量的要求（其梯度为零）则包含了上面关于在其中做惯性运动的物体的运动方程的内容.
因为在现有的广义相对论的理论框架下,等效原理是可以由其他假设推出.具体来说,就是如果时空中有一观者(G),则可在其世界线的一个邻域内建立的局域惯性参考系,而广义相对性原理要求该系中的克氏符（Christoffel symbols）在观者G的世界线上的值为零.因而现代的相对论学家经常认为其不应列入广义相对论的基本假设,其中比较有代表性的如Synge就认为：等效原理在相对论创立的初期起到了与以往经典物理的桥梁的作用,它可以被称之为“广义相对论的接生婆”,而现在“在广义相对论这个新生婴儿诞生后把她体面地埋葬掉”[2].
如果说到了二十世纪初狭义相对论因为经典物理原来固有的矛盾、大量的新实验以及广泛的关注而呼之欲出的话,那么广义相对论的提出则在某种意义下是“理论走在了实验前面”的一次实践.在此之前,虽然有一些后来用以支持广义相对论的实验现象（如水星轨道近日点的进动）,但是它们并不总是物理学关注的焦点.而广义相对论的提出,在很大程度上是由于相对论理论自身发展的需要,而并非是出于有一些实验现象急待有理论去解释的现实需要,这在物理学的发展史上是并不多见的.因而在相对论提出之后的一段时间内其进展并不是很快,直到后来天文学上的一系列观测的出现,才使广义相对论有了比较大的发展.到了当代,在对于引力波的观测和对于一些高密度天体的研究中,广义相对论都成为了其理论基础之一.而另一方面,广义相对论的提出也为人们重新认识一些如宇宙学、时间旅行等古老的问题提供了新的工具和视角.
相对论的应用
相对论主要在两个方面有用：一是高速运动（与光速可比拟的高速）,一是强引力场.
在医院的放射治疗部,多数设有一台粒子加速器,产生高能粒子来制造同位素,作治疗之用.由于粒子运动的速度相当接近光速(0.9c-0.9999c),故粒子加速器的设计和使用必须考虑相对论效应.
全球卫星定位系统的卫星上的原子钟,对精确定位非常重要.这些时钟同时受狭义相对论因高速运动而导致的时间变慢（-7.2 μs/日）,和广义相对论因较(地面物件)承受着较弱的引力场而导致时间变快效应（+45.9 μs/日).相对论的净效应是那些时钟较地面的时钟运行的快些.故此,这些卫星的软件需要计算和抵消一切的相对论效应,确保定位准确.[3]
过渡金属如铂的内层电子,运行速度极快,相对论效应不可忽略.在设计或研究新型的催化剂时,经常用上电脑模拟.这些程式便用上了相对论.
相对论指出,光速是信息传递速度的极限.超级电脑的总线时脉一般不能超越30GHz,否则在脉冲到达超级电脑的另一处之前,另一脉冲就已经发出了.结果电脑内不同地方的元件会不协调.相对论为超级电脑的布线长度和时脉上限提供了理论基础.
由广义相对论推导出来的引力透镜效应,让天文学家可以观察到黑洞和不发射电磁波的暗物质,和评估质量在太空的分布状况.
值得一提的是,原子弹的出现并非由于著名的质能关系式(E=mc2).质能关系式只是解释原子弹威力的数学工具而已.
Theory of relativity
From Wikipedia, the free encyclopedia
Jump to: navigation, search
This article is about the scientific concept. For philosophical or sociological theories about relativity, see Relativism. For the silent film, see The Einstein Theory of Relativity.
Two-dimensional projection of a three-dimensional analogy of space-time curvature described in General Relativity.The theory of relativity, or simply relativity, encompasses two theories of Albert Einstein: special relativity and general relativity.[1] However, the word "relativity" is sometimes used in reference to Galilean invariance.
The term "theory of relativity" was based on the expression "relative theory" (German: Relativtheorie) used by Max Planck in 1906, who emphasized how the theory uses the principle of relativity. In the discussion section of the same paper Alfred Bucherer used for the first time the expression "theory of relativity" (German: Relativitätstheorie).[2][3]
Contents [hide]
1 Scope
1.1 Two theory view
2 Special relativity
3 General relativity
4 See also
5 References
6 Further reading
7 External links
[edit] Scope
The theory of relativity enriched physics and astronomy during the 20th century. When first published, relativity superseded a 200-year-old theory of mechanics elucidated by Isaac Newton. It changed perceptions.[4][5][6]
For example, it overturned the concept of motion from Newton's day, into all motion is relative. Time was no longer uniform and absolute, as related to everyday experience. Furthermore, no longer could physics be understood as space by itself, and time by itself. Instead, an added dimension had to be taken into account with curved space-time. Time now depended on velocity, and contraction became a fundamental consequence at appropriate speeds.[4][5][6]
In the field of microscopic physics, relativity catalyzed and added an essential depth of knowledge to the science of elementary particles and their fundamental interactions, along with introducing the nuclear age. With relativity, cosmology and astrophysics predicted extraordinary astronomical phenomena such as neutron stars, black holes, and gravitational waves.[4][5][6]
[edit] Two theory view
The theory of relativity was representative of more than a single new physical theory. It affected the theories and methodologies across all the physical sciences. However, as stated above, this is more likely perceived as two separate theories. There are some related explanations for this. First, special relativity was published in 1905, and the final form of general relativity was published in 1916.[4]
Second, special relativity fits with and solves for elementary particles and their interactions, whereas general relativity solves for the cosmological and astrophysical realm (including astronomy).[4]
Third, special relativity was widely accepted in the physics community by 1920. This theory rapidly became a notable and necessary tool for theorists and experimentalists in the new fields of atomic physics, nuclear physics, and quantum mechanics. Conversely, general relativity did not appear to be as useful. There had appeared to be little applicability for experimentalists as most applications were for astronomical scales. It seemed limited to only making minor corrections to predictions of Newtonian gravitation theory. Its impact was not apparent until the 1930s.[4]
Finally, the mathematics of general relativity appeared to be incomprehensibly dense. Consequently, only a small number of people in the world, at that time, could fully understand the theory in detail. This remained the case for the next 40 years. Then, at around 1960 a critical resurgence in interest occurred which has resulted in making general relativity central to physics and astronomy. New mathematical techniques applicable to the study of general relativity substantially streamlined calculations. From this, physically discernible concepts were isolated from the mathematical complexity. Also, the discovery of exotic astronomical phenomena in which general relativity was crucially relevant, helped to catalyze this resurgence. The astronomical phenomena included quasars (1963), the 3-kelvin microwave background radiation (1965), pulsars (1967), and the discovery of the first black hole candidates (1971).[4]
[edit] Special relativity
Main article: Special relativity
USSR stamp dedicated to Albert EinsteinSpecial relativity is a theory of the structure of spacetime. It was introduced in Albert Einstein's 1905 paper "On the Electrodynamics of Moving Bodies" (for the contributions of many other physicists see History of special relativity). Special relativity is based on two postulates which are contradictory in classical mechanics:
The laws of physics are the same for all observers in uniform motion relative to one another (principle of relativity),
The speed of light in a vacuum is the same for all observers, regardless of their relative motion or of the motion of the source of the light.
The resultant theory agrees with experiment better than classical mechanics, e.g. in the Michelson-Morley experiment that supports postulate 2, but also has many surprising consequences. Some of these are:
Relativity of simultaneity: Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
Time dilation: Moving clocks are measured to tick more slowly than an observer's "stationary" clock.
Length contraction: Objects are measured to be shortened in the direction that they are moving with respect to the observer.
Mass-energy equivalence: E = mc2, energy and mass are equivalent and transmutable.
Maximum speed is finite: No physical object or message or field line can travel faster than light.
The defining feature of special relativity is the replacement of the Galilean transformations of classical mechanics by the Lorentz transformations. (See Maxwell's equations of electromagnetism and introduction to special relativity).
[edit] General relativity
Main article: General relativity
General relativity is a theory of gravitation developed by Einstein in the years 1907–1915. The development of general relativity began with the equivalence principle, under which the states of accelerated motion and being at rest in a gravitational field (for example when standing on the surface of the Earth) are physically identical. The upshot of this is that free fall is inertial motion; an object in free fall is falling because that is how objects move when there is no force being exerted on them, instead of this being due to the force of gravity as is the case in classical mechanics. This is incompatible with classical mechanics and special relativity because in those theories inertially moving objects cannot accelerate with respect to each other, but objects in free fall do so. To resolve this difficulty Einstein first proposed that spacetime is curved. In 1915, he devised the Einstein field equations which relate the curvature of spacetime with the mass, energy, and momentum within it.
Some of the consequences of general relativity are:
Clocks run more slowly in regions of lower gravitational potential.[7] This is called gravitational time dilation.
Orbits precess in a way unexpected in Newton's theory of gravity. (This has been observed in the orbit of Mercury and in binary pulsars).
Rays of light bend in the presence of a gravitational field.
Rotating masses "drag along" the spacetime around them; a phenomenon termed "frame-dragging".
The Universe is expanding, and the far parts of it are moving away from us faster than the speed of light.
Technically, general relativity is a metric theory of gravitation whose defining feature is its use of the Einstein field equations. The solutions of the field equations are metric tensors which define the topology of the spacetime and how objects move inertially.
相对论
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E = mc2相对论是关于时空和引力的理论,主要由爱因斯坦创立,依其研究对象的不同可分为狭义相对论和广义相对论.相对论和量子力学的提出给物理学带来了革命性的变化,它们共同奠定了近代物理学的基础.相对论极大的改变了人类对宇宙和自然的“常识性”观念,提出了“同时的相对性”、“四维时空”、“弯曲时空”等全新的概念.不过近年来,人们对于物理理论的分类有了一种新的认识——以其理论是否是决定论的来划分经典与非经典的物理学,即“非经典的＝量子的”.在这个意义下,相对论仍然是一种经典的理论.
目录 [隐藏]
1 狭义与广义相对论的分野
2 狭义相对论
3 广义相对论
4 相对论的应用
5 相对论对物理学发展的影响
6 文化影响
7 注释
8 参见
9 外部链接
狭义与广义相对论的分野
传统上,在爱因斯坦刚刚提出相对论的初期,人们以所讨论的问题是否涉及非惯性参考系来作为狭义与广义相对论分类的标志.随着相对论理论的发展,这种分类方法越来越显出其缺点——参考系是跟观察者有关的,以这样一个相对的物理对象来划分物理理论,被认为较不能反映问题的本质.目前一般认为,狭义与广义相对论的区别在于所讨论的问题是否涉及引力（弯曲时空）,即狭义相对论只涉及那些没有引力作用或者引力作用可以忽略的问题,而广义相对论则是讨论有引力作用时的物理学的.用相对论的语言来说,就是狭义相对论的背景时空是平直的,即四维平凡流型配以闵氏度规,其曲率张量为零,又称闵氏时空；而广义相对论的背景时空则是弯曲的,其曲率张量不为零.
狭义相对论
主条目：狭义相对论
爱因斯坦在他1905年的论文《论动体的电动力学》中介绍了其狭义相对论.
狭义相对论建立在如下的两个基本公设上：
狭义相对性原理（狭义协变性原理）：一切的惯性参考系都是平权的,即物理规律的形式在任何的惯性参考系中是相同的.这意味着物理规律对于一位静止在实验室里的观察者和一个相对于实验室高速匀速运动着的电子是相同的.
光速不变原理：真空中的光速在任何参考系下是恒定不变的,这用几何语言可以表为光子在时空中的世界线总是类光的.也正是由于光子有这样的实验性质,在国际单位制中使用了“光在真空中1/2,9979,2458秒内所走过的距离”来定义长度单位“米”（米）.
在狭义相对论提出以前,人们认为时间和空间是各自独立的绝对的存在.而爱因斯坦的相对论首次提出了时空的概念,它认为时间和空间各自都不是绝对的,而绝对的是一个它们的整体——时空,在时空中运动的观者可以建立“自己的”参照系,可以定义“自己的”时间和空间（即对四维时空做“3＋1分解”）,而不同的观者所定义的时间和空间可以是不同的.具体的来说,在闵氏时空中,而如果一个惯性观者（G）相对于另一个惯性观者（G'）在做匀速运动,则他们所定义的时间（t与t'）和空间({x,y,z}与{x',y',z'})之间满足洛伦兹变换.而在这一变换关系下就可以推导出“尺缩”、“钟慢”等效应,具体见狭义相对论条目.
在爱因斯坦以前,人们广泛的关注于麦克斯韦方程组在伽利略变换下不协变的问题,也有人注意到过爱因斯坦提出狭义相对论所基于的实验（如光程差实验等）,也有人推导出过与爱因斯坦类似的数学表达式（如洛伦兹变换）,但只有爱因斯坦将这些因素与经典物理的时空观结合起来提出了狭义相对论,并极大的改变了我们的时空观.在这一点上,狭义相对论是革命性的.
广义相对论
主条目：广义相对论
在本质上,所有的物理学问题都涉及采用什么时空观的问题.在二十世纪以前的经典物理学里,人们采用的是牛顿的绝对时空观.而相对论的提出改变了这种时空观,这就导致人们必须依相对论的要求对经典物理学的公式进行改写,以使其具有相对论所要求的洛伦兹协变性而不是以往的伽利略协变性.在经典理论物理的三大领域中,电动力学本身就是洛伦兹协变的,无需改写；统计力学有一定的特殊性,但这一特殊性并不带来很多急需解决的原则上的困难；而经典力学的大部分都可以成功的改写为相对论形式,以使其可以用来更好的描述高速运动下的物体,但是唯独牛顿的引力理论无法在狭义相对论的框架体系下改写,这直接导致爱因斯坦扩展其狭义相对论,而得到了广义相对论.
爱因斯坦在1915年左右发表的一系列论文中给出了广义相对论最初的形式.他首先注意到了被称之为（弱）等效原理的实验事实：引力质量与惯性质量是相等的（目前实验证实,在10 − 12的精确度范围内,仍没有看到引力质量与惯性质量的差别）.这一事实也可以理解为,当除了引力之外不受其他力时,所有质量足够小（即其本身的质量对引力场的影响可以忽略）的测验物体在同一引力场中以同样的方式运动.既然如此,则不妨认为引力其实并不是一种“力”,而是一种时空效应,即物体的质量（准确的说应当为非零的能动张量）能够产生时空的弯曲,引力源对于测验物体的引力正是这种时空弯曲所造成的一种几何效应.这时,所有的测验物体就在这个弯曲的时空中做惯性运动,其运动轨迹正是该弯曲时空的测地线,它们都遵守测地线方程.正是在这样的思路下,爱因斯坦得到了其广义相对论.
系统的说,广义相对论包括如下几条基本假设[1].：
广义相对性原理（广义协变性原理）：任何物理规律都应该用与参考系无关的物理量表示出来.用几何语言描述即为,任何在物理规律中出现的时空量都应当为该时空的度规或者由其导出的物理量.
爱因斯坦场方程（详见广义相对论条目）：它具体表达了时空中的物质（能动张量）对于时空几何（曲率张量的函数）的影响,其中对应能动张量的要求（其梯度为零）则包含了上面关于在其中做惯性运动的物体的运动方程的内容.
因为在现有的广义相对论的理论框架下,等效原理是可以由其他假设推出.具体来说,就是如果时空中有一观者(G),则可在其世界线的一个邻域内建立的局域惯性参考系,而广义相对性原理要求该系中的克氏符（Christoffel symbols）在观者G的世界线上的值为零.因而现代的相对论学家经常认为其不应列入广义相对论的基本假设,其中比较有代表性的如Synge就认为：等效原理在相对论创立的初期起到了与以往经典物理的桥梁的作用,它可以被称之为“广义相对论的接生婆”,而现在“在广义相对论这个新生婴儿诞生后把她体面地埋葬掉”[2].
如果说到了二十世纪初狭义相对论因为经典物理原来固有的矛盾、大量的新实验以及广泛的关注而呼之欲出的话,那么广义相对论的提出则在某种意义下是“理论走在了实验前面”的一次实践.在此之前,虽然有一些后来用以支持广义相对论的实验现象（如水星轨道近日点的进动）,但是它们并不总是物理学关注的焦点.而广义相对论的提出,在很大程度上是由于相对论理论自身发展的需要,而并非是出于有一些实验现象急待有理论去解释的现实需要,这在物理学的发展史上是并不多见的.因而在相对论提出之后的一段时间内其进展并不是很快,直到后来天文学上的一系列观测的出现,才使广义相对论有了比较大的发展.到了当代,在对于引力波的观测和对于一些高密度天体的研究中,广义相对论都成为了其理论基础之一.而另一方面,广义相对论的提出也为人们重新认识一些如宇宙学、时间旅行等古老的问题提供了新的工具和视角.
相对论的应用
相对论主要在两个方面有用：一是高速运动（与光速可比拟的高速）,一是强引力场.
在医院的放射治疗部,多数设有一台粒子加速器,产生高能粒子来制造同位素,作治疗之用.由于粒子运动的速度相当接近光速(0.9c-0.9999c),故粒子加速器的设计和使用必须考虑相对论效应.
全球卫星定位系统的卫星上的原子钟,对精确定位非常重要.这些时钟同时受狭义相对论因高速运动而导致的时间变慢（-7.2 μs/日）,和广义相对论因较(地面物件)承受着较弱的引力场而导致时间变快效应（+45.9 μs/日).相对论的净效应是那些时钟较地面的时钟运行的快些.故此,这些卫星的软件需要计算和抵消一切的相对论效应,确保定位准确.[3]
过渡金属如铂的内层电子,运行速度极快,相对论效应不可忽略.在设计或研究新型的催化剂时,经常用上电脑模拟.这些程式便用上了相对论.
相对论指出,光速是信息传递速度的极限.超级电脑的总线时脉一般不能超越30GHz,否则在脉冲到达超级电脑的另一处之前,另一脉冲就已经发出了.结果电脑内不同地方的元件会不协调.相对论为超级电脑的布线长度和时脉上限提供了理论基础.
由广义相对论推导出来的引力透镜效应,让天文学家可以观察到黑洞和不发射电磁波的暗物质,和评估质量在太空的分布状况.
值得一提的是,原子弹的出现并非由于著名的质能关系式(E=mc2).质能关系式只是解释原子弹威力的数学工具而已.