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22:01
@EmilioPisanty I do not know where to find that long chatroom discussion
22:15
I seem to have forgotten calculus.
right now I seem to have forgotten E&M. or at least I can't figure out what the right assumptions to make for this problem
I start with a parallel plate capacitor, and then move one of the plates transversely
so now the two plates overlap for some region but not for the entire area
doing this exactly would of course be cray cray so one needs to make approximations
@Semiclassical Any time I see the words "start with a parallel plate capacitor" I want to run away thanks to the horrific memories of undergrad finals :P
loool
the question really comes down to "how will the charges distribute"
I have to show a nonlinear differential operator is C^1 in the Frechet sense on W^{2,p}
I wonder which one of us is worse off @Semiclassical
also, the charge on each plate is fixed (not the potential)
Probably you.
22:23
@Semiclassical ugh I have forgotten all of analysis 1
I need to look up how partial derivatives work
ugh, I know that feeling
the operator is defined on a product of Banach spaces, so it's probably good enough to compute the partials and show they're continuous
and for that it's probably good enough to compute the Gateaux derivatives...
@Semiclassical ah, Berger, my favorite calculus book
he begins the chapter on "elementary calculus" with Bochner integration of Banach-space valued functions
@Semiclassical it's a bit tongue in cheek
@0celo7 of course, for my part the perversity is that i'm checking the logic by using a finite elements package
soooo I probably can't complain
22:34
Maybe I can just write "clearly" and everyone will believe me
It's quite believable
but I reaaaaally don't want to do an $\epsilon-\delta$ proof if I can avoid it
It is easy to see that $\Gamma$ is $C^1$ in the Fr\'echet sense and that its partial derivative in the $u$ direction is given by
$$D_1\Gamma(u,R)v=-a\Delta v-v-(2^\star-1)Ru^{2^\star-2}v,\quad v\in W^{2,p}.$$
how can you argue with that logic
I certainly can’t.
I’m a bit annoyed at the prof for thIs problem tbh
It’s tractable if one makes some approximations but he doesn’t say what assumptions they can make
And that makes no small difference since one of the usual answers to this kind of problem only makes sense if the overlap is large
god
I don't understand math
I should make some spaghett
At the gym. Working on arms and chest. May be abs too.
If you’re going to have problems that can’t be done exactly, you should specify what assumptions can be made
Otherwise it’s an exercise in ‘guess what the prof wanted’
@Semiclassical is this for your EM class?
22:59
@BalarkaSen yo where u at
@0celo7 yeah, it was one of their hw problems
And I’m writing up the solutions
@Semiclassical Of course, this one reminds me of the Astro fluid dynamics questions. It turned out that I wasn't able to do Astro fluid dynamics at all
23:26
@BalarkaSen Suppose I have a smooth function $f$ on a compact Riemannian manifold $M$. Can I find a smooth diffeomorphism $\phi$ of $M$ such that $f\circ\phi$ is close to $\inf f$ for a set of arbitrarily small comeasure?
Like, I want to smear out the region around $\inf f$ to be almost all of $M$
the goal being that $\|f\circ\phi-\inf f\|_{L^p}<\varepsilon$
@BalarkaSen In other words, can I find a diffeomorphism that takes a $\delta$-ball around a $p\in M$ to $U\subset M$ with measure$(M\setminus U)<\varepsilon$
vzn
vzn
23:58
@Slereah just take the red pill™ already... and see how far down the rabbit hole goes™! :P (ps wondering/ curious, how do you get that bohmian mechanics is a "mainstream" theory?)

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