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Electron band structure in germanium, my ass (2001)

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Re: Electron band structure in germanium, my ass (2001)

#41

Post by lazide »

ssivark wrote: post #28
janandonly wrote: post #2

It takes a special kind of mind to appreciate this short post, not as fiction, but as truth and also as a jab at the physics sciences in general.

Why is it a jab at physics? It's honest and beautiful -- I imagine this is exactly what an experience on the cutting edge of experiment is like! :D Making this measurement (an ancient discovery) with latest equipment is easy, but imagine what it might have been like for the people who actually discovered this property of germanium . Our tools/probes cannot advance much faster than our understanding of a (related) sub…

Especially when the entire concept might seem absolutely absurd at the time.

Re: Electron band structure in germanium, my ass (2001)

#42

Post by throwway120385 »

ssivark wrote: post #28
janandonly wrote: post #2

It takes a special kind of mind to appreciate this short post, not as fiction, but as truth and also as a jab at the physics sciences in general.

Why is it a jab at physics? It's honest and beautiful -- I imagine this is exactly what an experience on the cutting edge of experiment is like! :D Making this measurement (an ancient discovery) with latest equipment is easy, but imagine what it might have been like for the people who actually discovered this property of germanium . Our tools/probes cannot advance much faster than our understanding of a (related) sub…

I mean if you didn't already know how to solder to Germanium crystals you would have had to spend months experimenting with the material before you could get leads to stick.

Re: Electron band structure in germanium, my ass (2001)

#43

Post by PaulHoule »

hydrogen7800 wrote: post #33
jerf wrote: post #27

One of my Core Memories when it comes to science, science education, and education in general was in my high school physics class, where we had to do an experiment to determine the gravitational acceleration of Earth. This was done via the following mechanism: Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopw…

>Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopwatch when the ball hits the floor. Our class had some kind of device that would either punch a hole, or make a mark on paper at a regular time interval. We attached a narrow strip of paper to the ball, and let it pull through the marking device as it fell from…

... like something that burns a hole in the paper with a spark or marks thermal paper with a burst of heat.

Re: Electron band structure in germanium, my ass (2001)

#46

Post by jpm_sd »

A classic I will never not upvote.

Maybe the frustrations of undergrad lab work would be easier to swallow if they were better situated in historical context. This kind of result should give the experimenter some sympathy for the folks who originally made these discoveries, with less knowledge and worse equipment. But I don't think it's usually explained that way.

Re: Electron band structure in germanium, my ass (2001)

#47

Post by bee_rider »

jerf wrote: post #27

One of my Core Memories when it comes to science, science education, and education in general was in my high school physics class, where we had to do an experiment to determine the gravitational acceleration of Earth. This was done via the following mechanism: Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopw…

That’s pretty bad. On top of being unfair, it was a total missed opportunity to talk about the law of large numbers (I wonder if they could get a decent sample by combining everybody’s measurements) or skew (maybe everybody is a couple milliseconds too low just based on reaction time).

Or there could be some air resistance if you used, like, ping-pong balls.

Re: Electron band structure in germanium, my ass (2001)

#48

Post by mystified5016 »

throwway120385 wrote: post #36
hydrogen7800 wrote: post #33

Earlier quoted context omitted.

>Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopwatch when the ball hits the floor. Our class had some kind of device that would either punch a hole, or make a mark on paper at a regular time interval. We attached a narrow strip of paper to the ball, and let it pull through the marking device as it fell from…

That's an interesting way to measure the passage of time -- just use something that produces a "regular distance" and derive a way from kinematics to calculate the acceleration from the change in the distance.

The way boats historically measured speed was by dragging a rope behind them. The rope has knots tied with exact spacing. You drop one end of the rope in the water, and count how many knots pass you in a given time. That's then your speed in knots.

Re: Electron band structure in germanium, my ass (2001)

#49

Post by WhitneyLand »

jerf wrote: post #27

One of my Core Memories when it comes to science, science education, and education in general was in my high school physics class, where we had to do an experiment to determine the gravitational acceleration of Earth. This was done via the following mechanism: Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopw…

So did you let this go without protest? Why not escalate it if it was clearly so unreasonable?

Sounds like there was more nuance to the story.

Re: Electron band structure in germanium, my ass (2001)

#50

Post by npongratz »

jerf wrote: post #27

One of my Core Memories when it comes to science, science education, and education in general was in my high school physics class, where we had to do an experiment to determine the gravitational acceleration of Earth. This was done via the following mechanism: Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopw…

> From grade school on, you are graded on whether or not the grading authority likes the results you got.

I took an exam in a high school science class where I answered a question with the textbook's definition exactly as presented in the textbook, complete with the page number the definition was found on. I knew a bit about the topic, so I then cited outside scientific sources that explained why the definition was incomplete. There wasn't enough room to complete my answer in the space provided, so I spiraled it out into the margins of the exam paper.

My teacher marked my answer wrong. Then crossed that out and marked it correct. Then crossed that out, and finally marked it wrong again. During parent-teacher conferences, the science teacher admitted that even though I answered the question with the exactly correct definition, my further exposition made him "mad" (his word), and because he was angry, he marked it wrong.

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