作者:李海芯
By haixin Li
在科学这座圣殿里,
没有蛮横的神兽,
只有驯服的宠物。。
In the Temple of science, there are no wild beasts, only tame pets.
物理学上有四大神兽,芝诺的乌龟,拉普拉斯兽、麦克斯韦妖、薛定谔的猫。分别对应着微积分、经典力学、热力学第二定律和量子力学。这四大神兽并不弱于中国传说中的青龙白虎朱雀玄武。芝诺的乌龟时空双修能缩地成寸,拉普拉斯兽明察大道推演万物,麦克斯韦妖操控万物逆转阴阳,薛定谔的猫能制造宇宙超越生死。这四大神兽亦正亦邪,它既给聪明的科学家带来困扰,也给企图进化成神的人类指明了道路。
There are four great beasts of physics, Zeno's tortoise, Pierre-simon Laplace's beast, Maxwell's demon, and Schrödinger's cat. That corresponds to calculus, classical mechanics, Second law of thermodynamics and quantum mechanics. These four mythical beasts are no less powerful than the legendary blue dragon, White Tiger, Red Sparrow, and basalt.Zeno's tortoise can double in size in time and space. The Laplacian sees everything on the way, and the Maxwell's demon controls everything to reverse yin and yang, the Schrödinger's cat that makes the universe, beyond life and death. These four mythical beasts are both good and evil, and they both puzzle intelligent scientists and point the way for human beings to evolve into gods.
1.
薛定谔的猫
Schrödinger's cat
出生日期:1935年 主人:薛定谔
门派:量子力学 能力:超越生死
Date of birth: 1935 Host: Schrodinger, sect: quantum mechanics, ability: Beyond Life and death
埃尔温·薛定谔(Erwin Schrödinger,1887〜1961年)奥地利物理学家,量子力学奠基人之一,发展了分子生物学。维也纳大学哲学博士。苏黎世大学、柏林大学和格拉茨大学教授。因发展了原子理论,和狄拉克(Paul Dirac)共获1933年诺贝尔物理学奖。又于1937年荣获马克斯·普朗克奖章。他在德布罗意物质波理论的基础上,建立了波动力学,他建立的薛定谔方程是量子力学中描述微观粒子运动状态的基本定律,它在量子力学中的地位大致相似于牛顿运动定律在经典力学中的地位。提出薛定谔猫思想实验,试图证明量子力学在宏观条件下的不完备性。亦研究有关热学的统计理论问题。主要著作有《波动力学四讲》《统计热力学》《生命是什么--活细胞的物理面貌》等。
在20世纪,物理帝国妖风四起。一个毫无杀伤力但又难缠的神兽伴随量子力学空降人间,这神兽诞生于史上最风流的物理学家薛定谔的手上,遂名曰薛定谔之猫。
In the 20th century, the physics empire was in full swing. A harmless but unwieldy mythical beast descended from the hands of Schrodinger, the most amorous physicist in history, with quantum mechanics, and became known as Schrodinger's cat.
相比起前面那三个神通广大的神兽们,薛定谔之猫命运最悲催,它既不能享受吞拿鱼味儿的猫罐头,也没有猫奴给它献殷勤,自始至终,它都活在物理帝国的刑场上,并练就了既死又活的本事。这个刑场是一个密室,刑具是锤子和毒药瓶,这个锤子由电子开关控制,而电子开关又由放射性原子控制。如果原子核衰变,则放出阿尔法粒子,触动电子开关,猫必死无疑。不过,原子核的衰变是随机事件。尽管人们能精确知道原子核衰变时刻的概率,却无法判断它具体何时衰变。所以,尽管薛定谔之猫必死无疑,人们却无法得知它具体何时死亡。这么说来,打开密室前,这猫要么活着,要么死去。
Schrödinger's cat suffered the worst fate of all, not being able to enjoy a tuna-flavored can of cat food or being courted by a cat slave, all the while, it lives in the physical empire on the execution ground, and has developed the ability to both live and die. The place of execution was a secret chamber, with a hammer and a poison bottle, controlled by an electronic switch, which in turn was controlled by a radioactive atom. If the nucleus decays, it releases a alpha particle that triggers an electronic switch and the cat dies. However, nuclear decay is a random event. Although people can know the exact probability of the nuclear decay time, but can not tell when it decay. So although Schrödinger's cat is certain to die, it is impossible to know when it will. So the cat is either alive or dead until the Chamber of Secrets is opened.
可事情却没这么简单,因为,这只悲摧的猫被赋予了量子世界的特异功能——量子叠加,在这猫身上,宏观世界的因果律业已坍塌,只剩下一连串的概率波。所以,在被观测之前,这猫都是既死又活、生死叠加。
But it's not as simple as that, because this sad cat has been given a special power of the quantum world -- quantum superposition, in which the laws of causality in the macroscopic world have collapsed, leaving only a series of probability waves. Therefore, before being observed, the cat is both dead and alive, life and death superposition.
虽然薛定谔创造这只神兽仅是为了方便吃瓜群众们从宏观尺度理解量子物理,但它很快成了大家的噩梦,各类解说和研究纷至沓来。1957年,埃弗莱特用“多世界理论”给这只猫找到了归宿。他认为,问题并不在于盒子中的放射性原子是否衰变,而在于它既衰变又不衰变。薛定谔之猫是条活生生的生命,在它被观测那一刻,世界分裂成了两个版本,在A版本中,猫活着,而B版本中,猫死去。然而,尽管“多世界理论”非常优美,却被哥本哈根派这个量子力学头号教派极力打压,遂鲜为人知。所以,这只可怜的猫咪,依旧游荡在人界、地狱之间的灰色空间。
Although Schrödinger created the mythical beast only to make it easier for the masses to understand quantum physics on a macro scale, it quickly became a nightmare for everyone, with explanations and research pouring in. In 1957, Everett used the“Many worlds theory” to find a home for the cat. The problem, he argues, is not whether the radioactive atom in the box decays, but whether it does and does not. Schrödinger's cat is a living being. At the moment it is observed, the world splits into two versions. In version A, the cat lives, and in version B, the cat dies. However, although the“Many worlds theory” is very beautiful, but by the Copenhagen School of quantum mechanics, the number-one sect was severely suppressed, so little known. So, this poor cat, still wandering in the gray space between the human world and Hell.
尽管行走于生死边界的猫从未见过,但实验室的科学家却异口同声地证实他们见过薛定谔之猫的幽灵,你想象不出它活着的样子,但它却实际存在。有了微观世界的真实发现,又有团队谋划着把薛定谔之猫彻底带到宏观世界,挑战量子世界的边界。
Although the cat that walks the boundary between life and death has never been seen before, scientists in the lab have unanimously confirmed that they have seen the ghost of Schrödinger's cat. You Can't imagine it alive, but it exists. With the real discovery of the microcosm, another team plotted to bring Schrödinger's cat to the macrocosm, challenging the boundaries of the quantum world.
可迄今为止,量子理论尽管取得了伟大成就,但它仍然是物理帝国的一团乌云。也许,只有这两个世界真正携手的那一天,薛定谔之猫才能好好地安睡于天堂。
But so far, quantum theory, for all its achievements, remains a dark cloud on the physics empire. Perhaps Schrodinger's cat will sleep soundly in heaven only on the day when the two worlds truly join hands.
2
麦克斯韦妖
Maxwell's demon
出生日期:1871年 主人:麦克斯韦
门派:热力学 能力:逆转时空
Date of birth: 1871 owner: Maxwell, Sect: thermodynamics, ability: reversing time and space
詹姆斯·克拉克·麦克斯韦(James Clerk Maxwell,1831〜1879),出生于苏格兰爱丁堡,英国物理学家、数学家。经典电动力学的创始人,统计物理学的奠基人之一。麦克斯韦最重要的成就是建立了统一的经典电磁场理论和光的电磁理论,之后他还预言电磁波的存在。他的科学巨著《电磁学通论》,成为电磁学的重要基础,值得一提的是,麦克斯韦把电和磁两个学科内容分开,并且又大大扩张了电磁学的学科知识。麦克斯韦生前创办的卡文迪许实验室成为现在世界著名的学术中心之一。麦克斯韦被普遍认为是对物理学最有影响力的物理学家之一,没有电磁学就没有现代电工学,也就不可能有现代文明。
早在1200年,数以千计的科学家痴迷于永动机不能自拔。到了19世纪,热力学蓬勃发展,各类永动机一一被否定。这时候,让爱因斯坦都崇拜不已的电磁学大牛麦克斯韦做出了一个假说,从而诞生了物理学史上的第三大神兽——麦克斯韦妖。如果这神兽真的存在的话,或许就可以创立违背热力学第二定律的永动机就不是梦了,走向熵寂的宇宙也有起死回生的可能。
Back in the 1200, thousands of scientists were obsessed with the perpetual motion machine. In the 19th century, thermodynamics flourished and various perpetual motion machines were rejected. By this time, Maxwell, an electromagnetism guru whom Einstein had worshipped, had come up with a hypothesis that gave birth to the third most powerful animal in the history of physics -- the Maxwell's demon. If the mythical beast really existed, it might be possible to create Second law of thermodynamics perpetual motion machines. It wouldn't be a dream, but it would be possible to bring the dead back to life in a universe that went entropy-free.
麦克斯韦妖(Maxwell's demon),是在麦克斯韦假想的妖,能探测并控制单个分子运动,麦克斯韦意识到自然界存在着与熵增相拮抗的能量控制机制,但无法清晰说明这种机制,只能诙谐假定一种“妖”。简单描述,一个绝热容器被分成相等的两格,中间是由“妖”控制的一扇小“门”,麦克斯韦妖个头迷你,没啥特别的本事,但眼神好,反应敏捷,能准确地探测并控制单个分子运动,迅速把快速移动的分子从从左盒丢进右盒,把慢速运动的分子从右盒丢进左盒。因此,总有一个格子的温度是高于另一个格子,这个小盒子左右部分就形成了温差,实现了熵的自发减少,这样就可以违背热力学第二定律制作出第二类永动机。
Maxwell's demon, the Maxwell's demon of Maxwell's imagination that detects and controls the movement of individual molecules, realized that nature had an energy-control mechanism that resisted entropy, but can not clearly explain this mechanism, can only assume a witty“Demon”. In brief, an adiabatic container is divided into two equal compartments, with a small “Door” controlled by a “Demon” in the middle. The Maxwell's demon is small, not particularly skilled, but has good eyesight and quick reflexes, cAN accurately detect and control the movement of individual molecules, fast-moving molecules from the left box into the right box, the slow-moving molecules from the right box into the left box. So, there's always a lattice where the temperature is higher than the temperature of the other lattice, and the left and right parts of this little box form a temperature difference, which automatically reduces entropy, so you can go against the Second law of thermodynamics and make a Type 2 perpetual motion machine.
麦克斯韦妖的物理学意义是让混乱变得有序,避免封闭系统变成一潭死水。扩展到现实世界,那此神兽能就能操控万物,逆转阴阳。若是如此强大的小妖存在的话,人类也会进一步地进化,但在戒律森严的物理世界中,这样的小妖注定是命运多舛的。在20世纪50年代,信息熵的概念被提出。
The physics of Maxwell's demon is to keep chaos in order, to keep a closed system from becoming a backwater. Extend to the real world, then this spirit beast can control everything, reverse yin and yang. If such a powerful little demon existed, the human race would evolve further. However, in the strict world of physics, such a little demon was doomed to have an unfortunate fate. In the 1950s, the concept of information entropy was proposed.
麦克斯韦妖若要实现热力学上的熵减,势必需要获取分子运动的信息,不耗损能量而获得信息是不可能的,因此,在孤立系统中麦克斯韦妖不可能存在。归根结底,这个兢兢业业的小妖精可能只是人类想象中的救世主,不可能在时空中存在。
In order for a Maxwell's demon to achieve thermodynamic entropy reduction, it is necessary to obtain information about the motion of molecules. It is impossible to obtain information without losing energy, and therefore Maxwell's demon can not exist in an isolated system. In the final analysis, this hard-working goblin may only be the savior of the human imagination, can not exist in time and space.
不过,进入21世纪,学界痴迷于研究熵减过程,麦克斯韦妖再现踪迹。2007年2月发现一种人造麦克斯韦妖,通过“信息擒纵阀”使系统逐渐远离平衡态,只不过,这个人造麦克斯韦妖仍需要光作为能量源。
In the 21st century, however, academics have become obsessed with the process of entropy Maxwell's demon. A man-made Maxwell's demon was discovered in February 2007 that uses an “Information escapement valve” to steer the system away from equilibrium, but the man-made Maxwell's demon still needs light as a source of energy.
到如今,麦克斯韦妖存不存在还是不能被证明,也许在不久的未来,科学家们就能找到这样的小妖吧。如果它真的存在,那老人可以华发变成黑发,宇宙能从熵寂走向重生。从此,覆水可收,破镜重圆。那将是多么让人向往的世界啊。
Until now, the existence of Maxwell's demon has not been proven, and scientists may soon be able to find one. If it exists, the old man can turn grey into black, and the universe can move from entropy to rebirth. Since then, the water can be recovered, broken mirrorreunion. What a world that would be.
3
拉普拉斯兽
Laplace's beast
出生日期:1814年 主人:拉普拉斯
门派:经典力学 能力:推演万物
Date of birth: 1814 Master: Pierre-simon Laplace sect: classical mechanics, ability: deducing everything
皮埃尔-西蒙·拉普拉斯侯爵(Pierre-Simon marquis de Laplace,1749〜1827年),法国著名的天文学家和数学家,天体力学的集大成者。1749年生于法国西北部卡尔瓦多斯的博蒙昂诺日,1816年被选为法兰西学院院士,1817年任该院院长。1812年发表了重要的《概率分析理论》一书,在该书中总结了当时整个概率论的研究,论述了概率在选举审判调查、气象等方面的应用,导入”拉普拉斯变换“等。在拿破仑皇帝时期和路易十八时期两度获颁爵位。拉普拉斯曾任拿破仑的老师,所以和拿破仑结下不解之缘。拉普拉斯在研究天体问题的过程中,创造和发展了许多数学的方法,如以他的名字命名的拉普拉斯变换、拉普拉斯定理和拉普拉斯方程。
法国物理学家拉普拉斯,是号称"将上帝赶出宇宙"的人,他提出的拉普拉斯方程广泛应用于各个领域。他是经典力学的坚定拥护者,也是决定论的支持者。他吸纳了毕达哥拉斯“万物皆数”之力,结合天体力学、概率论等思想精华。所以他认为,当下的客观世界是过去的果和未来的因。
Pierre-simon Laplace, a French physicist who claims to have “Banished God from the universe”, has come up with a Laplace's equation that has wide application. He was a staunch supporter of classical mechanics and of determinism. He drew on the Pythagoras of “All things count”, combining ideas such as celestial mechanics and probability theory. So he believes that the objective world of the present is the consequence of the past and the cause of the future.
他认为这世间如果存在一种神兽,它神通广大,无所不知。只要它愿意动动手指和眼睛,记录下某一刻它能知道宇宙中每个原子确切的位置和动量,就能用牛顿的简洁公式,瞬间算出宇宙的过去与未来。这就是大名鼎鼎的神兽拉普拉斯,善推演,能知万物。
He believes that if there is a mythical beast in the world, it is powerful and omniscient. If it could simply record a moment with its fingers and eyes, knowing the exact position and momentum of every atom in the universe, it could instantly calculate the past and future of the universe using Newton's simple formula. This is the famous mythical Beast Pierre-simon Laplace, who is good at deduction and knows everything.
简而言之,拉普拉斯的理论就是:了解物质前一刻的运动状态,就可以推出下一刻的运动状态,把整个宇宙的每一个粒子的运动状态确定以后,就可以推出下一刻的运动状态。你们可以想象一下,假如从宇宙的起源到宇宙的发展再到宇宙的终结,全部的全部,只需要我知道宇宙最初的状态就可以推演出来,一切都只不过是定局,那会有多么的可怕。如果真的能实现,人类就掌握了宇宙的命运。
In short, Pierre-simon Laplace's theory is that by understanding the motion of matter in one moment, you can deduce the motion of matter in the next, and by determining the motion of every particle in the universe, you can deduce the state of motion of the next moment. If you can imagine, from the beginning of the universe to the development of the universe to the end of the universe, all of it, all I need to know about the original state of the universe is that it's all just a foregone conclusion, how terrible it would be. If it can be done, man will control the fate of the universe.
可大部分的人类却没有这么高兴,如果人类的所有命运都已经被拉普拉斯妖算得清清楚楚,那我们还有什么活头?必须得早点弄死它才行,不出一百年,热力学和量子力学等新理论对其万箭齐发,以物理学家开尔文以及量子力学的海森堡开始联手围剿,这只无所不能的拉普拉斯兽最终一命呜呼,可以算是夭折在了襁褓里。
But most of humanity is not so happy, if all the human destiny has been Laplace's demon clear, then we have no life? It had to be killed early, and within a hundred years, new theories such as thermodynamics and quantum mechanics were firing at it, with physicist Kelvin and quantum physicist Heisenberg joining forces, the omnipotent Laplacian eventually died, in what could be called a premature death.
19世纪,建立在不可逆基础上的热力学大行其道,这让以可逆性作为基石的拉普拉斯兽元气大伤。20世纪,困扰人类百年的双缝干涉实验成功证明因果律在微观世界彻底失效,而海森堡的测不准原理也说明再厉害的神兽也无法看清微观世界的全部面貌。
In the 19th century, the popularity of thermodynamics based on irreversibility undermined the Pierre-simon Laplace beast, whose foundation was reversibility. In the 20th century, the Young's double-slit experiment that plagued humanity for centuries proved that the laws of cause and effect had no effect on the microscopic world, and Heisenberg's uncertainty principle showed that no great beast could see the whole of the microscopic world.
4
芝诺的乌龟
Zeno's turtle
出生日期:公元前464年 主人:芝诺
门派:先贤哲学 能力:缩地成寸
Date of birth: AD 464 BC: Master: Zeno sect: Sage philosophy, ability: reduced to inch
芝诺(Zeno of Elea,约前490〜前425)生于意大利半岛南部的埃利亚城邦,古希腊数学家、哲学家。他是埃利亚学派的著名哲学家巴门尼德的学生和朋友。他的生平记载的已经不很清晰了,不过以他名字命名的芝诺悖论,却广为流传。芝诺悖论是一系列关于运动的不可分性的哲学悖论。由于量子的发现,这些芝诺悖论已经得到完善的解决。
公元前464年,物理帝国的世纪运动竞技开幕,芝诺之龟与海神之子阿喀琉斯赛跑。阿喀琉斯体格健壮,肌肉饱满,四肢遒劲有力。芝诺之龟短小精悍,豆眼如炬,龟甲结实笨重。芝诺之龟以身体劣势为由,申请提前奔跑100米。阿喀琉斯深知自己的速度乃是芝诺之龟的十倍,便毫不犹豫地答应了。
At the 464 BC of the physical age, the tortoise of Zeno races Achilles, son of the sea god. Achilles was strong, muscular, and powerful. Zeno's tortoise is small, beady-eyed and bulky. Zeno's tortoise applied to run the 100m ahead of schedule, citing physical disadvantage. Knowing that he was ten times faster than Zeno's tortoise, Achilles agreed without hesitation.
比赛开始,当阿喀琉斯追到100米时,乌龟已经向前爬了10米;阿喀琉斯继续追,而当他追完乌龟爬的10米时,乌龟又已经向前爬了1米;阿喀琉斯只能再追向前面的1米,可乌龟又已经向前爬了1/10米;就这样,芝诺之龟总能与阿喀琉斯保持一个距离,不管这个距离有多小,但只要乌龟不停地奋力向前爬,阿喀琉斯就永远也追不上乌龟!
At the start of the race, when Achilles reached 100 meters, the tortoise had already climbed 10 meters; Achilles continued to chase, and when he finished chasing the tortoise climbed 10 meters, the tortoise had already climbed 1 meter; Achilles could only run a metre further, but the tortoise had climbed a tenth of a metre further, and so the tortoise of Zeno always kept a distance from Achilles, no matter how small, but as long as the tortoise kept trying to climb forward, Achilles will never catch up with the tortoise!
尽管阿喀琉斯是全人类最顶尖的英雄,但最终败在芝诺之龟的四条小短腿之下,芝诺之龟从此暴得大名,无人匹敌。不仅在古希腊,同样智者云集的东方文明,也对这只乌龟无可奈何,《庄子·天下篇》中提到:“一尺之棰,日取其半,万世不竭”,其实也是这只龟的变种。这便是鼎鼎大名的芝诺悖论。
Although Achilles was the greatest hero of the human race, he was defeated by the four short legs of Zeno's turtle, and Zeno's turtle became famous. Not only in ancient Greece, but also in the eastern civilization, where the wise men were gathered, could do nothing about the tortoise. In Zhuangzi the world, it is said that “A stroke of a foot can be taken at half a day, and it can not be exhausted for all eternity.”, it's actually a variation of this turtle. This is known as the Zeno paradox.
其实在聪明的大家看来,这就是一个十分简单的问题。因为在现实世界中,随便拉来一只乌龟,无论它跑多远,6岁小儿都能追上它。而且,随便建立一个简单的方程组t=s/(v1-v2)还能求出阿喀琉斯追上芝诺的乌龟的时间。
In fact, in the eyes of smart people, this is a very simple problem. Because in the real world, a random turtle, no matter how far it runs, 6-year-old children can catch up with it. Moreover, a simple set of equations T = S (v1-v2) could be used to calculate how long it would take Achilles to catch up with Zeno's tortoise.
可是,在严谨的物理世界却不是这么一回事,万事万物都需要严谨的逻辑推算和证明才可以存在。也就是说,就算我们可以轻而易举地求出阿喀琉斯追上乌龟所用的时间,也仍不能证明他为何能够追上。要想解决这个问题就必须把极限问题给解决了。可是从毕达哥拉斯到欧拉的数学大神们,没有一个人能够破解极限问题的。因此,这毫无任何道理的芝诺的乌龟,以神兽的姿态定居在物理的帝国整整2000年。
However, in the rigorous physical world is not the case, everything requires rigorous logical reasoning and proof to exist. In other words, even if we could easily figure out how long it took Achilles to catch up with the tortoise, it still doesn't prove why he did. To solve this problem we must solve the limit problem. But no one, from the Pythagoras to Al-`Ula, has ever been able to crack the limit problem. Thus, the Zeno tortoise, which makes no sense at all, settled in the physical empire as a mythical beast for 2,000 years.
整整两千年后,数学巨匠莱布尼茨与科学巨匠牛顿隔空修炼“微积分”,用微积分中的“极限”法门攻破了时空连续性。这让大英雄阿喀琉斯终于在物理帝国的竞技场里,追上芝诺之龟。
Exactly 2,000 years later, the math giant Leibnitz and the science giant Newton practiced “Calculus” in isolation, using the “Limit” method of calculus to break the space-time continuum. This allowed the great hero Achilles to finally catch up with Zeno's tortoise in the arena of the physical empire.
回首古今,物理学的四大神兽都有了自己的结局。只能说无论是多么蛮横的神兽,在最后都会被科学收服,这也许就印证了开头的那句话吧。芝诺的乌龟已经死了,微积分的基础便是建立在它的尸体上。拉普拉斯兽被混沌效应的引入给推翻了,再加上后来的海森堡的临门一脚,也是凉透了。麦克斯韦妖将信息论中的信息量定义与热力学中的熵联系了起来,寻求到了自己新的保护门派。薛定谔的猫现在还是不知是死是活,躲在量子力派的屋檐下瑟瑟发抖。
Looking back at the past and present, the four great beasts of physics have their own ending. It can only be said that no matter how unruly the mythical beast, in the end will be accepted by science, this may prove the beginning of the sentence bar. Zeno's turtle is dead, and calculus is based on its corpse. The Laplacian was overthrown by the introduction of chaos and, later, by Heisenberg. By linking the definition of information in information theory to the entropy of thermodynamics, the Maxwell's demon sought a new school of its own. The Schrödinger's cat is still shivering under the eaves of the quantum school.
科学当道,神兽已矣。
Science is the way, the Spirit Beast has gone.
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