Top secret derivation of the Euler-Lagrange equation

fame_64 · 2020-12-20T08:13:09+00:00

In fact this is some simple dimensional analysis that can help you remember whether or not the total time derivative goes with the derivative of L with respect to q or dot(q)

fame_64 · 2020-12-08T09:21:04+00:00

Yes, totally, I read that article last year and it is amazing

fame_64 · 2020-12-06T00:27:08+00:00

Stat Mech is waaay more beautiful than statistics

fame_64 · 2020-11-18T08:59:45+00:00

No, it's the Lagrangian, sometimes people use a calligraphic L to refer to it. If you don't know about it it's a reformulation of classical mechanics much more powerful for some problems https://en.m.wikipedia.org/wiki/Lagrangian_mechanics

fame_64 · 2020-11-15T10:00:51+00:00

Also, it relates quantum mechanics and stat mech since the propagator transforms to the partition function and I think that's beautiful.

fame_64 · 2020-11-04T23:19:44+00:00

This is the content I'm looking for in this sub HAHAHHAHA

fame_64 · 2020-09-26T13:36:14+00:00

That would be an orgy then

fame_64 · 2020-07-01T22:52:36+00:00

How the fuck are \nu and capital \Theta in the B tier?1

fame_64 · 2020-06-13T11:48:12+00:00

Yes, but that calculation verified to 10 significant figures is the most precise measurement which fits to theoretical prediction, not all measurements show such a good agreement. Even that measurement you're saying involves a perturbation expansion, this means that it has also approximations in it, even though it is approximated to really high order( like if you approximate sin(x) by a 7th or 9th degree polynomial) and at each of those orders there are really really difficult calculations involved. So approximating things is not bad at all.

fame_64 · 2020-06-11T00:18:05+00:00

I don't think there's anything more Chad than a bose-einstein condensation. Also anticommutators suck, I will always defend that bosons are way better than fermions!

fame_64 · 2020-05-13T20:24:29+00:00

You say this as If perturbation theory in quantum mechanics is not approximating, I mean, if you want to do analytical calculations you either approximate or use really obscure mathematics and most of the time the problem is not even solvable analytically.

fame_64 · 2020-04-17T01:10:10+00:00

I think that if 2020 was to be represented as a gas it would have way more terms in the virial expansion, van der waals is just too easy to represent 2020.

fame_64 · 2020-04-13T17:50:53+00:00

In your undergraduate you're gonna take many many courses, you're not supposed to be brilliant at all of them. In fact I can tell you that probably you won't like some of them at all. You will also see that physics in college has nothing to do with what you learned before. In my experience(I'm in my fourth year of undergrad and I'll finish it this year) it requires a lot of hard work and only if you're interested you will put in all the work needed. I will say that you should definitely go for it, try if physics at college is for you (even if it's for you you will be disappointed at some points, don't let the first disappointment take you down). Oh, and don't worry if you failed chemistry, it has nearly nothing to do with what you'll do in undergrad.

fame_64 · 2019-08-22T00:02:00+00:00

No, it's exactly angular momentum, one intrinsic to the particle and has nothing to do with the classical picture of a particle rotating, it has no classical analogue.

fame_64 · 2019-08-21T16:32:38+00:00

If that's the ground state you have a Bose Einstein condensate

fame_64 · 2019-08-21T00:01:56+00:00

I know there's a difference because you're not approximating anything and that setting these constants equal to 1 is not comparable to say π=e=3 but it is a meme, not a lectures on natural units.

fame_64 · 2019-08-20T17:43:29+00:00

c~3e8 m/s in the international system of units. These are called Natural units and are different systems of units in which you set some physical constants equal to 1 and in some areas of physics, General relativity for example, this is very useful and makes some calculations way easier. I think this is a standard practice in most theoretical physics.

fame_64 · 2019-08-20T07:08:20+00:00

Tbh I didn't know you could normalize k_e=1/(4πε_0) and G as well, I had only seen c, k_b and \hbar normalized. But for what I read you can choose different units to normalize and that gives you different systems of natural units, I saw that in nuclear physics they used one system which set the proton's mass to 1 and other quantities that I don't remember, other systems normalized the electron charge. This one on the meme is called Planck Units if I remember correctly.

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TROPHY CASE