科学与数学pages.cs.wisc.edu
锗的电子能带结构，扯淡（2001）
Electron band structure in germanium, my ass (2001)
2011 — 2025，它一次次回到首页
黑点是上首页（≥ 50 分）的那次投稿，空心点是没冲上去的投稿，点越大分数越高。
导读
这是 Lucas Kovar 写的一篇著名的本科物理实验报告式吐槽：他想测锗的电子能带结构，却被糟糕的设备和噪声百出的数据打败，最后只能靠修饰甚至编造数据交差。文中还顺带猛烈嘲讽固体物理里大量“这么做就行”式的挥手近似。
为什么经久不衰：它把理工科实验课里人人见过却少人明说的失败、凑数据和拍脑袋近似写得既愤怒又好笑，二十多年后仍能让做过实验的人会心一笑。
HN 评论精选
教学实验设备与理论不符，学生被迫凑数据；摩擦实际上常是非线性的。
我初中就有过这个领悟：把木块叠在木块上或排成一列，用“测力计”去拉，以此测摩擦。那测力计不过是一根插在木块里的弹簧钢，末端带钩。在我试过的每个表面上它都完全非线性，书上却说应该是线性的。学生们都偷偷改数据，最后老师说“唉，按说它应该是线性的，你们尽量凑吧”。领悟：这一套都是扯淡。后来我才知道大多数材料的摩擦本来就完全非线性，但那是20年后才读到的。
JoeAltmaier查看英文原文
I had this insight in Junior High - testing friction by putting blocks on top of other blocks, or in a block train, and using a 'force meter' to see how hard I had to pull. The 'force meter' was a piece of spring steel stuck into another block, with a hook on the end. It was totally non-linear on every surface I tested. The book said it was supposed to be linear. The students were all furtively fudging it, and eventually the teacher said something like "well, its supposed to be linear so do the best you can". Insight: this was all a bunch of crap. Turns out that friction is totally non-linear anyway, for most materials, but I didn't read that until 20 years later.
固体物理教学充斥缺乏解释的近似，好教材才能让人理解。
他对固体物理里那些挥手近似说得太对了。所有物理领域都得用近似，但固体物理里的近似理由往往最糟，无非是“这样做就行”，甚至“不这样做就不行”。之后三门课（两门固体物理、一门电子学）一直如此。直到后来碰到一本像样的书，把一些近似解释得不让人尴尬，部分内容回头再看才明白；另一些仍是谜，大概永远都是。
perlgeek查看英文原文
He's so totally right about the hand waving approximations used in solid state physics. All fields of physics need to use some approximations, but those in the solid state were usually the ones with the worst reasons, just things like "it works if we do that" or even "it doesn't if we don't do this". It went on like that in three courses (two on solid state physics, one on electronics). Only after that did I happen to come across a decent book which explained some of the approximations in a way that didn't make me cringe, and some of the stuff started to make sense in retrospect. Others are still a mystery to me, and probably always will be.
这篇文章被业界人士看到，间接帮评论者进入游戏行业，也说明它为何反复被提起。
这篇“实验报告”总让我想起美好旧事，因为它间接开启了我的游戏行业生涯。2002年春我在UW Madison读CS，在Mike Gleicher的计算机图形实验室工作。此前通过同学Alex Mohr（现Pixar）认识Lucas。后来Ensemble Studios的AI程序员Mike Kidd联系Lucas；Mike是UW校友，看过这篇锗的论文，想让Lucas去申请ES。一个月后，Lucas知道我很想进游戏业，就把Mike的邮件转给我并推荐了我。长话短说，我拿到ES面试，毕业就进了梦想工作。期待几年后这个链接再冒出来 :)
laeus查看英文原文
This "lab report" always brings back good memories because it indirectly launched my career in the game industry. I was finishing up my CS degree at UW Madison and working in Mike Gleicher's computer graphics lab in Spring '02. I had previously met Lucas through a fellow CS student (Alex Mohr, now at Pixar). At some point, Lucas was contacted by the AI programmer at Ensemble Studios (Mike Kidd). Mike, a UW alum, had seen the Germanium treatise and wanted Lucas to apply at ES. A month later, knowing how eager I was to join the game industry, Lucas mentioned Mike's email to me and forwarded him my info. Long story short, I got an interview at ES and was hired straight out of college into a dream job. I look forward to seeing this link pop up again in a few years. :)
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