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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)

#231
post #176

Earlier quoted context omitted.

Yes, my strict adherence to “trust but verify” was born from literal tears. It’s not worth trusting others if it takes a small fraction of the projects time to verify. It has saved me incredible amounts of time in my professional life, and I’ve seen months wasted, and projects delayed, by others who hadn’t cried enough yet.

I would love to hear some of your examples, if only to reinforce your lesson to myself.

“Is the box plugged in? Did you cycle the power?”

I’ll trust that you understand each of those words individually but later verify that the box is actually plugged in.

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

#232
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…

My physics professor told us once about a lab he had to do when he was a student himself, about measuring the adiabatic gas constant of air. The workload at that point was immense, so lots of students would just write a report and give the textbook answer—and be marked wrong. It turned out the TA had sabotaged the experiment by putting alcohol in the bottom of the (dark glass) measurement bottle, so the measurement w…

The trouble with these kinds of games is that they put the more diligent students at a disadvantage. For example, someone might compare their experimental result against the textbook constant, realise it's wrong, and spend much more time trying to identify their "mistake", not realising they've been sabotaged. This puts further pressure on their other work.

One cannot argue that this is fair on the basis that it's the "real world", because all that does is reward the sloppier (middle) approach. It filters the very lazy from the average, but at the expense of the excellent.

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

#233
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…

On a side note, one thing every single one of my peers who have pursued a creative degree have echoed, be it architecture, literature, graphic design, industial design etc. - is that the only way to get a good grade is to find out what your professors personal preferences and opinions are and be in total and utter agreement with them.

Any amount of critical views tends to result in your work torn to pieces and you getting a shitty grade.

Your architecture professor likes turrets? Then better put them even on the chicken coop - that way he'll no you're one of the students who gets it.

Your lit professor loves a certain philosopher? - better not point out that you find his arguments circular, ponderous and betraying a lack of broad perspective.

This has been utterly weird to me considering I have encountered way less (but not zero) of this thing in engineering, and art is supposed to be about developing your self-expression, but I've heard this criticism so many times from so many places and formulated so strongly. I've had many people flat out leave their educations because of this, with others just quietly powering through.

This in of itself has changed my view of art education, and I've told many people to stay away from these places not because of the usual 'it's useless and you'll starve to death arguments' but because of this.

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

#234
post #141

Earlier quoted context omitted.

It's funny, because while that's a terrible educational experience, you actually learned some important lessons despite them. I remember the first time I found out that the software documentation I had been relying upon was simply and utterly wrong. It was so freeing to start looking at how things actually behaved instead of believing the utterly false documentation because the world finally made sense again.

I took and then TA'd a class where the semester long project was to control robots (it was a software engineering principles class, the actual code writing could be done in a single weekend, but you had to do all the other stuff of software engineering- requirements analysis and documentation etc). We had a software simulator of the robots, and the first lab was everyone dutifully writing the code that worked great o…

> because the simulator had a bug

I had something similar happen when I was taking microcomputers (a HW/SW codesign class at my school). We had hand-built (as in everything was wire wrapped) 68k computers we were using and could only download our code over a 1200-baud serial line. Needless to say, it was slow as hell, even for the day (early 2000s). So, we used a 68k emulator to do most of our development work and testing.

Late one night (it was seriously like 1 or 2 am), our prof happened by the lab as we were working and asked to see how it was going. I was project lead and had been keeping him apprised and was confident we were almost complete. After waiting the 20 minutes to download our code (it was seriously only a couple dozen kb of code), it immediately failed, yet we could show it worked on the simulator. We single-stepped through the code (the only "debugger" we had available was a toggle switch for the clock and an LED hex readout of the 16-bit data bus). I had spent enough time staring at the bus over the course of the semester that I'd gotten quite good at decoding the instructions in my head. I immediately saw that we were doing a word-compare (16-bit) instead of a long-compare (32-bit) on an address. The simulator treated all address compares are 32-bit, regardless of the actual instruction. The real hardware, of course, did not. It was a simple fix. Literally one-bit. Did it in-memory on the computer instead of going through the 20-minute download again. Everything magically worked. Professor was impressed, too.

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

#235

Earlier quoted context omitted.

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.

Google said (AI result): Soldering a lead to a germanium crystal typically involves using a gold-germanium solder alloy (like 88% gold, 12% germanium) due to its compatibility and good bonding properties Also one of the search results implied etching first could help remove germanium oxide and used a different solder: https://www.researchgate.net/post/How-to-solder-germanium-wa... Plus you'd need to decide how to get…

In most but the very richest physics research groups there are no such thing called technicians. Except for shared equipment in centralized managed facilities like the nanofabs, even there you need to tune your own recipe...

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

#236
post #218

Earlier quoted context omitted.

That's a tragic story. However, I'm surprised that the transistor was supposed to come in a DIP package. Usually through-hole discrete transistors come in a three-lead package like TO-92. Of course, that would not have helped you since yours looked like every other student's except the for the markings.

Probably Darlington transistors like ULN2003

ULN2003 is not DIP8

And I would assume for pedalogical purposes a bare transistor would be preferred rather than the '2008 with its extra diodes and base resistor.

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

#237
post #170
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…

At my high school, somehow physics was the dumb jock science course. I think it was because the head football coach taught physics for decades before retiring my sophomore year. Anyway, as a kid who was doing well in school and was headed for college, it was a natural decision for me to not bother taking physics and study for the AP test on my own. But one day a kid showed up in one of my classes with a hall pass for…

Now I feel lucky to have gone to a school where universally the teachers actually understood the material they were teaching. The only poor teaching I had to face was on the teaching aspects, and this was only from a minority of teachers.

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

#238
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…

> 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. Wouldnt've helped me before late high school, but that "whether or not the grading authority likes the results you got" part cuts both ways . That is, if you put som…

Well, on the flip side, I had a couple of classes in which we were supposed to "critique" papers, for the laudable purpose of learning critical thinking skills and how to evaluate papers.

We also were supposed to read the greatest papers in the field to learn about the field from the primary sources, also a laudable purpose.

Unfortunately, these two things were put together, and we were expected to produce "critiques" of the greatest papers in the field.

Now, I've told this story a couple of times, and always some anklebiter jumps up from the replies to point out that even the greatest papers can have mistakes or be improved or whatever. Which is in principle true. But when Einstein comes up to you and for the first time in world history explicates his new theory of relativity, you aren't doing him, yourself, or the world a favor by "critiquing" his choice of variable names, quibbling about his phrasing, or criticizing him for not immediately knowing how to explain it the way physicists will explain it after over 120 years of chewing on it.

In practice, there is no practical way to "critique" these papers. They are the ones that have slugged it out with hundreds of thousands of other papers to be getting recommended to undergraduate students 20-40 years later. There is no reason to believe that anything a college junior, even one from decades down the line, is going to give any suggestions that can improve such papers.

So what I learned is that I can just deploy a formula: 1. Summarize the paper quickly, ideally with some tidbit in it that proves you really read it 2. Use my decades of foresight to complain that the author didn't do in this paper something the field built on it later, quite possibly led by the same author (I dunno, I didn't check of course, I'm just complaining) 3. Say "more research is needed"... it's a cliche for a reason -> Get an A every single time, despite putting no real cognitive effort into the critique.

I did at least read the papers for real, and that was fine, but my "critique" was 100% presentation, 100% genuflection of the ritual words of science, knowingly shorn of meaning. Heck, even now I don't think I feel bad about that; I just delivered what was asked for, after raising the objection once. At least we read some of the literature, and that is a skill that has served me for real, in real life, even though I did not go into academia proper.

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

#240
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…

In my high school, without naming any names, the teacher told us all that anyone who changed their results to 9.81m/s^2 was doing science incorrectly. And we were graded on our analysis of the experimental procedure, or something like that.
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