朱八八

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历史上最天才的学霸和学渣，时间最公平吗？非也！

(2019-03-01 07:31:05) 下一个

01

ETH可是当时世界顶级名校, 培养了二十多名诺贝尔奖获得者.

02

（朱八八认为，学渣爱因斯坦的话还是比较靠谱的，尤其是狭义相对论。第一种说法绝对只是江湖传说。相对论现在已经是理工科必修课程。）

（狭义相对论用到的数学，也就基本相当于大学本科的水平，包括洛伦兹变换和简单的微积分。有兴趣的童鞋可以去看看推导过程，其实不会比你们参加过的高考更难。）

03

《晋书》曾记载：“王质入山斫木，见二童围棋。坐观之，及起，斧柯已烂矣。”

“天上方一日，世上已千年”以前只是神话传说，学渣爱因斯坦居然提出了科学解释。樵夫烂柯人也许是第一个有记载的经历虫洞或者时空隧道的人类。

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nightrider @朱朱八八:

You said "文章说的是光速在真空中的速度，不是在不同介质的速度". That is not an essential difference. Vacuum is a just special medium. More importantly, the equations itself say nothing about μ and ε, whether they are constant or dependent on space. The derivation of the wave equation is the same independent of whether μ and ε are functions of space. Maxwell's equations say nothing about in what medium the electromagnetic disturbance is traveling in. As a matter of fact, there needs to be an exogenous assumption on in what medium the wave is propagating in. There was even a name for this medium the light is propagating in, ether. One important contribution Einstein made was the complete elimination of ether and postulate that the electromagnetism creates its own field and the light travels in this field.

More importantly, you have confused different notions of constancy of light. The revolutionary notion Einstein put forward is that the speed of light is invariant with respect to different inertial frames in vacuum, not that the speed is constant at different spatial point in vacuum in one frame. This is NOT expressed by the formula c=sqrt（1/μ0ε0), but by the Lorentzian transform group or the inertial frame invariance of space-time, which is the core of the special relativity.

bashfulx vacuum Is a just special case of medium.
permitivity or permeability of vacumm has to have a value or values. It is simple to assume a constant value than uncertain possibilities of values

nightrider "麦克斯韦方程可以推导出真空中电磁波速是常数c=sqrt（1/μ0ε0)." No. Like I said, c is a constant only when μ0ε0 is a constant. You can derive the the wave equation with speed c=sqrt（1/με). But the Maxwell's equations do not specify whether με is a constant. For example, for light traveling in an isotropic medium rather than a vacuum. μ and ε depend on the medium and can even be made to depend on the position in the medium by changing the density or structure of the medium. The Maxwell's equations themselves do not assume the constancy of μ and ε and therefore the constancy of c=sqrt（1/με).

XYZ3 至少老爱高中毕业时他的数学/物理老师，还有校长，认为他是应该去上ETH的。 那就是认可他的高中学习成绩的。 至于他高中复读了一年，是因为ETH物理系本科每年收人太少。 它家的挑剔性接近于现在美国许多博士项目。

XYZ3 他成绩不好，怎能考上ETH?不是说ETH物理系那年才5个人毕业？瑞士联邦苏黎世高等工学院应该至少是整个德语区最好的2-3所工学院。 那个年代应该是整个德语区有志于理工科的高中生向往的地方。

bashfulx I can understand relativity theory now.
But I cannot wrap my mind around quantum physics.
The particle wave duality, the uncertainty principle, the spooky interactions, the delayed choice, etc. etc
nightrider Interesting article. Maxwell's equations do not imply the constancy of the speed of light. It is a simple function of the permitivity and permeability of vacuum, just as you write in your article, the constancy of which is not specified by the equations themselves but depends on exogenous assumptions. Einstein's special relativity postulates the speed of light is constant or that both the permitivity and permeability of vacuum are constant.

eater111 爱因斯坦成绩不好可能是误解。这人从小就很聪明，只不过不看重成绩和考试罢了。
hhspiny 我不这么认为。你可以去读Einstein的论文，不可能是一个不好好学习没有基础的人能写得出来的