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Boosted by jwz:
kjhealy ("Kieran Healy") wrote:

The most compact, informative, and useful introduction to the Philosophy and Sociology of Science remains Kovar (2001), “Electron Band Structure in Germanium, My Ass”.

Electron Band Structure in Germanium, My Ass Lucas Kovar University of Wisconsin, Madison 2001* Abstract The exponential dependence of resistivity on temperature in germanium is found to be a great big lie. My careful theoretical modeling and painstaking experimentation reveal 1) that my equipment is crap, as are all the available texts on the subject and 2) that this whole exercise was a complete waste of my time. Introduction Electrons in germanium are confined to well-defined energy bands that are separated by "forbidden regions" of zero charge-carrier density. You can read about it yourself if you want to, although I don't recommend it. This relation between temperature and resistivity can be shown to be exponential in certain temperature regimes by waving your hands and chanting "to first order". Experiment Procedure I sifted through the box of germanium crystals and chose the one that appeared to be the least cracked. Then I soldered wires onto the crystal in the spots shown in figure 2b of Lab Handout 32. Do you have any idea how hard it is to solder wires to germanium? I'll tell you: real goddamn hard. The solder simply won't stick, and you can forget about getting any of the grad students in the solid state labs to help you out. *Originally published at https://pages.cs.wisc.edu/*kovar/. Archived version available at https://web.archive.org/web/20070622110041/http://pages.cs.wisc.edu/~kovar/hall.html
Figure 1: Check this shit out. Once the wires were in place, I attached them as appropriate to the second-rate equipment I scavenged from the back of the lab, none of which worked properly. I soon wised up and swiped replacements from the well-stocked research labs. This is how they treat undergrads around here: they give you broken tools and then don't understand why you don't get any results. In order to control the temperature of the germanium, I attached the crystal to a copper rod, the upper end of which was attached to a heating coil and the lower end of which was dipped in a thermos of liquid nitrogen. Midway through the project, the thermos began leaking. That's right: I pay a cool ten grand a quarter to come here, and yet they can't spare the five bucks to ensure that I have a working thermos. Results Check this shit out (Fig 1). That's bonafide, 100%-real data, my friends. I took it myself over the course of two weeks. And this was not a leisurely two weeks, either; I busted my ass day and night in order to provide you with nothing but the best data possible. Now, let's look a bit more closely at this data, remembering that it is absolutely first-rate. Do you see the exponential dependence? I sure don't. I see a bunch of crap. Christ, this was such a waste of my time. Banking on my hopes that whoever grades this will just look at the pictures, I drew an exponential through my noise.