Anonymous at Tue, 2 Jul 2024 19:43:54 UTC No. 16264814

>>16264709
It's extraordinarily well written, brief, and provides a unique perspective on mechanics by starting with the principle of least action. Its derivations are sound if a little elliptic. If this troubles you, I recommend supplementing Sternberg's "Lectures on Differential Geometry" and Olver's "Applications of Lie Groups to Differential Equations". The blanks, however, are not difficult to fill.
>VI Arnold
Wrote a book on symplectic geometry on top of classical mechanics. It is very much in the spirit of Landau, thus a nice supplement or book on the former in case you want to study that in particular. The physical content is the same.

To put it briefly, Landau Lifshitz treats a large variety of physical topics in a self-contained manner all while not underestimating the reader's ability to expand the mathematical arguments if needed. If you lack mathematical maturity in those areas you may consider reading other books.

Anonymous at Tue, 2 Jul 2024 20:10:31 UTC No. 16264852

>>16264814
Have you carefully read L&L? I think you are full of shit. The books are genuinely bad.

Anonymous at Tue, 2 Jul 2024 20:12:12 UTC No. 16264855

>>16264709
>Why do physicists worship books that are full of false claims
because they were written by jews, and jews are sacred.

Anonymous at Tue, 2 Jul 2024 20:13:36 UTC No. 16264857

>>16264855
No. Plenty of great books that I love have been written by jews (e.g. VI Arnold's book as already mentioned). The books are just bad and the only sensible explanation I am able to come up with is that physicists aren't able to follow arguments and think carefully.

Anonymous at Tue, 2 Jul 2024 20:14:37 UTC No. 16264861

>>16264855
Also fuck off back to >>>/pol/. I don't want this thread to be derailed into idiotic neo-nazism.

Anonymous at Tue, 2 Jul 2024 20:22:11 UTC No. 16264883

>>16264814
>Its derivations are sound if a little elliptic
Yeah you obviously haven't gone through the book if you say that.

Anonymous at Tue, 2 Jul 2024 20:27:26 UTC No. 16264891

>>16264709
>full of false claims, nonsensical proofs and incorrect definitions
Post 5 examples.

Anonymous at Tue, 2 Jul 2024 20:46:00 UTC No. 16264910

>>16264891
For a start, already on page 4.
1. Doesn't explain why the interactions can be ignored after far away distance.
2. Doesn't explain why the lagrangian is additive in the limit.
3. Doesn't explain how the additiveness removes the invariance under constant multiplication.

Anonymous at Tue, 2 Jul 2024 20:59:23 UTC No. 16264928

>>16264910
Here Landau demonstrates the inability to distinguish between the claim A=>B and B=>A.

Anonymous at Tue, 2 Jul 2024 21:08:17 UTC No. 16264947

Most of the bottom page is just nonsense. Why does the second term being a total time derivative mean it's a linear function of velocity? If anyone here actually went through and understood the book they would be able to explain it easily, but I expect this to either be ignored or to get accused for being dumb/just not understanding basic things (things that they can't explain anyhow).

Anonymous at Tue, 2 Jul 2024 21:27:00 UTC No. 16264979

>>16264947
[eqn]\frac{d}{dt}f(\vec q,t) = \vec \nabla f (\vec q,t) \cdot \vec v + \frac{\partial}{\partial t} f(\vec q,t) [/eqn]
There are no non-linear [math]\vec v[/math] terms on the RHS. This is basic chain-rule shit. You were expected to have learned this in your Calculus class.

Anonymous at Tue, 2 Jul 2024 21:35:42 UTC No. 16264990

>>16264979
The basic equation you posted is obviously true but you might as well said 2+2=4 hence it's true. It doesn't follow.

Anonymous at Tue, 2 Jul 2024 21:39:31 UTC No. 16264995

>>16264979
You're clearly unable to provide an actual explanation for what Landau claimed, only to show an elementary equation and claim without evidence that it implies the claim made in the book. IMO this proves what I said in the OP. You actually don't understand it either and are grasping at straws.

Anonymous at Tue, 2 Jul 2024 21:47:19 UTC No. 16265006

>>16264990
>>16264995
Explain exactly which part is unclear then.

Anonymous at Tue, 2 Jul 2024 22:09:05 UTC No. 16265033

>>16265006
>>16264979
Why are you considering only functions of the form f(q, t) rather than f(q, q', t), as is the form of the lagrangian?

Anonymous at Tue, 2 Jul 2024 22:14:58 UTC No. 16265041

>>16265033
The total time derivative of a function of the form [math]f(q, \dot q, t)[/math] would have [math] \ddot q [/math] terms which is not allowed in a Lagrangian in Classical Mechanics.

Anonymous at Tue, 2 Jul 2024 22:21:50 UTC No. 16265049

>>16265041
Ok, then my issue with this boils down to the issue outlined before: why does it follow that the second term is a total time derivative?

Anonymous at Wed, 3 Jul 2024 01:45:02 UTC No. 16265261

>>16264861
>asks why physics is a fucked up discipline
>angry because he got the answer
Don’t ask questions you don’t want to know the answer to

Anonymous at Wed, 3 Jul 2024 06:57:14 UTC No. 16265582

>>16264861
pushing for censorship is a sign of low IQ and dogmatism tho...
as the other anon said... don't ask if you don't want to know the real answer.
read anthropology treaties about foundation myths and taboos if you want to enlighten yourself.

Anonymous at Wed, 3 Jul 2024 07:13:04 UTC No. 16265591

>>16264947
>building infinitesimal gobbledigook on top of cryptic language
doesn't using an inertial frame of reference just mean you're focusing on a certain non-accelerating object to determine the positions and momentum of other objects?
infinites is where our math ceases to make sense in the real world, see all the schizophrenia about white/black holes being time portals etc.