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Electron band structure in germanium, my ass (2001)
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7 days agoby tux3
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 stopwatch when the ball hits the floor.

Anyone who has ever had a wristwatch of similar tech should know how hard it is to get anything like precision out of those things. It's a millimeter sized button with a millimeter depth of press and could easily need half a second of jabbing at it to get it to trigger. It's for measuring your mile times in minutes, not fractions of a second fall times.

Naturally, our data was total, utter crap. Any sensible analysis would have error bars that, if you treat the problem linearly, would have put 0 and negative numbers within our error bars. I dutifully crunched the numbers and determined that the gravitational constant was something like 6.8m/s^2 and turned it in.

Naturally, I got a failing grade, because that's not particularly close, and no matter how many times you are solemnly assured otherwise, you are never graded on whether you did your best and honestly report what you observe. From grade school on, you are graded on whether or not the grading authority likes the results you got. You might hope that there comes some point in your career where that stops being the case, but as near as I can tell, it literally never does. Right on up to professorships, this is how science really works.

The lesson is taught early and often. It often sort of baffles me when other people are baffled at how often this happens in science, because it more-or-less always happens. Science proceeds despite this, not because of it.

(But jerf, my teacher... Yes, you had a wonderful teacher who didn't only give you an A for the equivalent but called you out in class for your honesty and I dunno, flunked everyone who claimed they got the supposed "correct" answer to three significant digits because that was impossible. There are a few shining lights in the field and I would never dream of denying that. Now tell me how that idealism worked for you going forward the next several years.)

7 days agoby jerf
I read this in 1999 when entering university. It was so refreshing hearing a student provide a glimpse into the boots-on-the-ground reality of undergrad life at these world-renowned institution.

The closing sentence is also prescient; the author pivoted to CS, ultimately completing his doctorate at the University of Wisconsin at Madison

https://pages.cs.wisc.edu/~kovar/

7 days agoby roadbuster
I TAd a semiconductor fabrication lab class 20-odd years ago. Mostly it was about making sure the students had the absolute fear of God put into them about working with HF, but there was also a bit at the end where you actually got to do a voltage sweep and characterize your transistor. If in fact you had made a transistor rather than a needlessly complicated resistor. The other TAs and I passed this paper around and thought it was just hilarious.
7 days agoby sevensor
This reminds me of how the Fahrenheit scale came about.

For all its flaws, Fahrenheit was based on some good ideas and firmly grounded in what you could easily measure in the 1720s. A brine solution and body heat are two things you can measure without risking burning or freezing the observer. Even the gradations were intentional: in the original scale, the reference temperatures mapped to 32 and 96, and since those are 64 units apart, you could mark the rest of the thermometer with a bit of string and some halving geometry. Marking a Celsius scale from 0 to 100 accurately? Hope you have a good pair of calipers to divide a range into five evenly-spaced divisions...

Nowadays, we have machines capable of doing proper calibration of such mundane temperature ranges to far higher accuracy than the needle or alcohol-mix can even show, but back then, when scientists had to craft their own thermometers? Ease of manufacture mattered a lot.

7 days agoby shadowgovt
Oh, BTW, the whole "Friction is directly proportional to the normal force": My Ass!

I could never reproduce it well in the lab, because it's really not true. Take a heavy cube the shape of a book. Orient it so that the spine is on the floor. It's a lot more friction to move it in one direction than in the transverse direction. Yet the normal force is the same. Any kid knows this, and I feel dumb it never occurred to me till someone pointed it out to me.

7 days agoby BeetleB
> Sorry! The URL you requested was not found on our server.

404 error now, perhaps some admins took it down due to traffic?

The user's directory is still linked from the listing [0] though.

[0] https://pages.cs.wisc.edu/

6 days agoby Terr_
Seriously I wish more science writing resembled this
7 days agoby skrebbel
I'll repeat the same comment I made to the same article when it posted here about a year ago:

As an odd coincidence, I did the same experiment on a shoestring budget with substandard equipment also. I too used a fancy computer algorithm to get a best fit. Except that I managed to get four significant decimal places in the result — an improvement over the (also outdated) textbook.

The author of the angry rant had a life-defining experience of overwhelming frustration.

The same scenario resulted in a positive life-defining experience for me

It’s funny how unpredictably things pan out even in identical circumstances…

7 days agoby jiggawatts
Try faking your data next time, dude! You will be famous for some time. Do you even know how hard it is to make data points that seem natural but follow some clear pattern you want it to follow? I spent a good half of a day looking for that proper inverse formula.
7 days agoby aramattamara
A+, recommending for accelerated PhD program.
7 days agoby NoMoreNicksLeft
so funny. i've read a few chapters of Discworld books that made me titter a lot less
7 days agoby wigster
my ass analyzed here https://youtu.be/1P0Z1yq-2FQ
6 days agoby vagy
Nice chart. Can't rule out the old null hypothesis eh!
7 days agoby blatantly
ROTFL at the abstract
7 days agoby aledalgrande
Nobel prize, quick!
7 days agoby huqedato