Space and time

Day 1

Vocabulary：

This idea was first stated explicitly in Newton’s Principia Mathematica, published in 1687, and is known as Newton’s first law.

1.explicitly：

Fully and clearly expressed;leaving nothing

implied:explicit approval；Fully developed or formulated:has an explicit idea of what to say in the

paper.；Forthright and unreserved in

expression:They were explicit in their criticism.；Readily observable:an explicit sign of trouble；Describing or portraying nudity or sexual activity ingraphic detail.

synonyms:accuratecertainclearcorrectdefinitedefinitiveexactobviouspositiveprecisestraightforward

eg：He was quite explicit as to what he expected us to do for him.

2.Newton’s first law:whenever a body isnot acted on by any force, it will keep on moving in a straight line at thesame speed.In aninertial

reference frame, an object either remains at rest or continues tomove at a constantvelocity, unless acted upon by aforce

3. What happens to a body when a force does act on itis given byNewton’s second law. This states that the bodywill accelerate, or change its speed, at a rate that is proportional to theforce.

4．Newton’s second law:In an inertial reference frame, the vectorsumoftheforcesFon an object is equal to themassm of that object multiplied by theaccelerationaof the object: F=ma.

The acceleration is also smaller the greater themass(or quantity ofmatter) of the body.物体的加速度跟物体所受的合外力成正比，跟物体的质量成反比，加速度的方向跟合外力的方向相同。

5．Mass：a shape or

three-dimensional volume that has or gives the illusion of having weight,

density, and bulk

If the law were that the gravitationalattraction of a star went down faster or increased more rapidly with distance,the orbits of the planets would not beelliptical,they would eitherspiralintothe sun or escape from the sun

6.elliptical：a plane curve such that the sums of the distances of each point in its

periphery from two fixed points, the foci, are equal.；tending to be ambiguous,

cryptic, or obscure；(of speech or writing) expressed with

extreme or excessive economy; relieved of irrelevant matter

Eg：The same goes for theellipticalmachine hunger strike, which also

comes off as tonally deficient, to say the least.

7.spiral:n.Geometry.a plane curve generated by a point moving around a

fixed point while constantly receding from or approaching it; a helix;a single

circle or ring of a spiral or helical curve or object;adj:running

continuously around a fixed point or center while constantly receding from or

approaching it; coiling in a single plane;V:to take a spiral form or course;to advance or increase

steadily; rise

Eg:In practice, we have

mechanisms such as warranties which can halt thespiral.

When the famousDr. Johnson was told of Berkeley’s opinion, he cried, “Irefuteit thus!” andstubbed his toeon a large stone.

8.refute：to prove to be false or erroneous, as an opinion or

charge.

to prove (a person) to be in error.

Eg：To be sure, Mitt Romney's unpopularity mightrefutethis theory, but even so, Bartlett is

talking about something important here

9.stubone’stoe：to strike accidentallyagainst a projecting object

Istubbed my toe against the step.

Shorter wavelengths are known as microwaves (afew centimeters) orinfrared(morethan a ten-thousandth of a centimeter)

10.infrared

noun

1.the part of the invisible spectrum that iscontiguous to theredend of the visible spectrum and that comprises electromagnetic radiation ofwavelengths from 800 nm to 1 mm.

adjective

2.noting or pertaining to the infrared or itscomponent rays:

infrared radiation.

It was therefore suggested that there was asubstance called the "ether"that was present everywhere, even in"empty" space

11.ether:Chemistry, Pharmacology.a colorless, highly volatile, flammable liquid, C4H10O,

having an aromatic odor and sweet, burning taste, derived from ethyl alcohol by

the action of sulfuric acid: used as a solvent and, formerly, as an inhalant

anesthetic.

以太：由希腊学者提出，认为是光传播的介质

Between 1887 and 1905 there were severalattempts, most notably by the Dutch physicist Hendrik Lorentz, to explain theresult of the Michelson-Morley experiment in terms of objectscontractingand clocks slowingdown when they moved through the ether

12.contract:an agreement between two or more parties for the doing or not doing of

something specified; to wrinkle; to draw together or into smallercompass; draw the parts of together; to incur, as a liability orobligation

The

publisher contracted the artwork.

In effect, themeter is defined to be the distance traveled by light in

0.000000003335640952 second, as measured by acesiumclock.

13.cesium:a rare, highly reactive, soft, metallic element of the alkali metalgroup, used chiefly in photoelectric cells.Symbol:Cs;atomic

weight

Maxwell’s equation predicts that the speed of lightshould be the same whatever the speed of the source

14.无论你站在地上，还是站在飞奔的火车上，测得的光速都是一样的。这就是狭义相对论的第二个基本原理：光速不变原理

15.cone:a solid whose surface isgenerated by a line passing through a fixed point and a fixed plane curve notcontaining the point, consisting of two equal sections joined at a vertex;aplane surface resembling the cross section of a solid cone.

16.geodesic:Also,geodesical. pertaining to the geometry of curved surfaces,in whichgeodesic linestake the place of the

straight lines of plane geometry.

17.hilly:full ofhills; having manyhills;hilly

country.;resembling ahill;elevated; steep.

Eg:Aletter-carrier will cover thirty-five miles ofhillyroad as an ordinary day's march, and

more if haste is enjoined.

18.rotate:to cause to turn around an axis or center point;revolve.

to cause to go through a cycle of changes; cause topass or follow in a fixed routine of succession:to rotate farm crops;to replace (a person, troops, etc.) by another or others, usually

according to a schedule or plan.

Eg:The sentries rotated in keeping watch.

19.finite:having bounds or limits; not infinite; measurable.

Mathematics;(of a set of elements) capable of being completelycounted;not infinite or infinitesimal;not zero；subject to limitations or conditions, as of space,time, circumstances, or the laws of nature:man's finite existence on earth.4.somethingthat is finite.

Eg:Theenvironment is vulnerable,finite, and must at all costs be protected

20.（1）引力红移：广义相对论证明，引力势低的地方固有时间的流逝速度慢。也就是说离天体越近，时间越慢。这样，天体表面原子发出的光周期变长，由于光速不变，相应的频率变小，在光谱中向红光方向移动，称为引力红移。宇宙中有很多致密的天体，可以测量它们发出的光的频率，并与地球的相应原子发出的光作比较，发现红移量与相对论预言一致。60年代初，人们在地球引力场中利用伽玛射线的无反冲共振吸收效应（穆斯堡尔效应）测量了光垂直传播22。5M产生的红移，结果与相对论预言一致。

（2）光线偏折：如果按光的波动说，光在引力场中不应该有任何偏折，按半经典式的"量子论加牛顿引力论"的混合产物，用普朗克公式E=hv和质能公式E=Mc^2求出光子的质量，再用牛顿万有引力定律得到的太阳附近的光的偏折角是0.87秒，按广义相对论计算的偏折角是1.75秒，为上述角度的两倍。1919年，一战刚结束，英国科学家爱丁顿派出两支考察队，利用日食的机会观测，观测的结果约为1.7秒，刚好在相对论实验误差范围之内。引起误差的主要原因是太阳大气对光线的偏折。最近依靠射电望远镜可以观测类星体的电波在太阳引力场中的偏折，不必等待日食这种稀有机会。精密测量进一步证实了相对论的结论。

（3）水星近日点的进动：天文观测记录了水星近日点每百年移动5600秒，人们考虑了各种因素，根据牛顿理论只能解释其中的5557秒，只剩43秒无法解释。广义相对论的计算结果与万有引力定律（平方反比定律）有所偏差，这一偏差刚好使水星的近日点每百年移动43秒。

（4）雷达回波实验：从地球向行星发射雷达信号，接收行星反射的信号，测量信号往返的时间，来检验空间是否弯曲（检验三角形内角和）60年代，美国物理学家克服重重困难做成了此实验，结果与相对论预言相符。

Day 2

经过第一天看12页不停地虐，看着群里的大家讨论得好热烈，认真地想想安妮说的由于光速不一样而导致相对时间错过太阳对地球的告白，好浪漫，但浪漫归浪漫，还是要好好啃科学呢。其实看了理论物理之后，发现自己之前看得实在是太少了，懂得的也实在是太少了，虽然总结这件事不是今天的任务，但是还是有感而发，发了再说呢，之前看三体的时候大刘会涉及很多科学知识在其中，自己很多时候其实都是不求甚解，但今天真的当成任务去完成的时候，开始静下心来理解，虽然理论物理是有点晦涩难懂，但霍金的语言却尽量让故事较为生动吧（至少还算生动吧orz：））而自己觉得群里大家的讨论自己常常无法参与其中，是自己没有问题要问呢，还是自己的逻辑思维已经没有好奇心？想想真可怕。

1.impulse:  [physics]

a.the product of the average magnitude of a forceacting on a body and the time for which it acts

b.the change in the momentum of a body as a result of a force acting upon it for a short period of time

eg:My first impulse was to run away.

2.bother: to make (a person) alarmed orconfused

eg:Don't bother to search for it.

3.ultraviolet ：of electromagnetic radiation) having a wavelength shorter than that of the violet end of the visible spectrum but longer than that of X-rays.

4.equivalence :the condition of being equal or equivalent in value, worth, function, etc..

synonyms: equality, sameness, interchangeability, comparability

Functional equivalence,hardly gettable for a translator,is positively significant as a translation norm.

先大概写这么多，吸收一下昨天的单词和里面的科学内容吧

唉总结一下，自己最近状态不行，可能是因为自己忙着写毕业论文，再加上自己还有雅思要考，导致最近两天的作业，先说说看时间简史这本书，一开始看到这本书觉得还好吧，科学应该挺有意思的，虽然自己平时不怎么看，后来终于想起为什么自己会不看，就是看不懂啊，大写的看不懂，但是安妮讲解后，还有大神的讨论之后，总算是有丢丢看懂了，虽然还是有些疑惑，但是感觉自己懂了一些理论科学的问题。

对于一些自己不懂的专业知识，觉得了解得真的很少，如果一个月前有人告诉我，我会读时间简史，我可能会笑出来，纳闷怎么可能，但是知识一直就在那里，等你去接触到的时候，你会发现这是一个全新的世界，一个文科生就是把这种理论当成故事去看，但是很多理论的来由还是不懂。但不管怎么说，接触到理论物理这一完全不懂的领域还是觉得有学到东西的，之前看到一篇文章，说现在的学生其实很多东西都是知之甚少，你问热带雨林是什么，也许有学生会回答巴西，有学生会回答森林，甚至还有人会说和氧气有关的，但是热带雨林究竟是什么，没有多少人能完整地表述出来，那么对于相对论这个概念，我们很多人也是这样，如果之前你问我相对论是什么，我只能告诉你这是爱因斯坦的发明，还有一个笑话，就是在喜欢的女生面前时间过得很快，而不喜欢的事情面前时间过得很慢，这就是时间的相对。但真正走入这个理论世界，很多脑洞真的会让我们爆炸，我，讲真第一次知道，时间真的不是绝对的。

当然自己看得太仓促了，觉得自己的思维导图和安妮的还是有很多不一样，很多细节没有把握，后面的一些实验还在啃。刚刚走了一遍鲸鱼的简书，觉得最大的感触还是鲸鱼引用国富论的那句话：这一点是近期同时在精读班与生活中的体悟，也让我想起了曾经纠结是否要看斯密的《国富论》时偶然看到的一句话：“在写国富论的时候，是开辟混沌之时，我要的是国富论的思维逻辑和对于社会的辩证经济化的思想。这本书一定要看，人的思维逻辑没有过时和不过时之说。”