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WalterBrighttoday at 2:23 AM2 repliesview on HN

One physics exam question I remember was derive Maxwell's Equations from the starting point of presuming the existence of magnetic monopoles. This sounds like an intractable problem, but it turned out that if you really understood how they were derived, all you had to do was switch out the charge monopoles with the magnetic monopoles, and it was a piece of cake.

A similar exam problem in AMA95 was to derive the hyperbolic transforms. The trick there was to know how the Fourier transforms (based on sine/cosine) were derived, and just substitute in sinh/cosh.

If you were a formula plugger or just memorized facts, you'd be dead in the water.


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pyuser583today at 8:36 AM

Reminds me of this article - https://firstthings.com/math-is-erotic/ - strangely titled “Math is Erotic” but talking about the relationship between Maxwells Equation and water waves, and magneticism.

godelskitoday at 5:15 AM

I do think that's one of the reasons it's easier to do in physics. You're taught to see math as a language and therefore need to interpret it. With that in mind who cares if you memorize formulas and can churn out some algorithmic computation. You'll memorize formulas "accidentally" as you use them frequently. But if you don't know how to interpret the math you're completely fucked and frankly probably won't do well as a physicist. Much of the job is translating back and forth.

I actually loved my classical mechanics class. The professor was really good and in the homeworks he'd come up with creative problems. The hardest part was always starting. Once you could get the right setup then you could churn away like any other (maybe needing to know a few tricks here and there).

Coming over to CS I was a bit surprised how test based things were. I'm still surprised how everyone thinks you can test your program to prove its correctness. Or that people gravely misinterpret the previous sentence as "don't write tests" rather than "tests only say so much"

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