@StanShunpike it is not the language, it is speed. I usually take question that require calculi. And until I do the calculi the question gets lost in the site, it is not a fresh one. Also, I edit very slowly, s.t. my answer is the last one, and people don't go so far with reading answers.
@KyleKanos I have no idea, it's not my domain. I see in general questions in my domain, and I rarely see such a logos (speech) of calculi as mine. But it may be that GR is more interesting.
I do! I rave about this place. My family doesn't get it. But I actually taught my sister how to do partial derivatives with Lagrangians yesterday and she was sooo excited
@JimdalftheGrey do you know what is his biggest defect (i.e. of the skeleton)? That the skull doesn't have ears, s.t. I could pull at them and make them long up to the sky.
During a question on SO, whilst the question remained somewhat ambiguous a potential answer was downvoted. No explanation of the downvote was made to the poster, nor was there any reason for that one answer to be singled out.
The answer had a slight flaw in it, but at the time numerous answers h...
That's fine, I'm not taking issue with your upvote to offset a downvote -- that's your prerogative even though I personally don't care for it. But there is no policy or suggestion to explain downvoting, that's what I am pointing out
The downvote is most likely because it is a homework-and-excercises question that makes no effort to solve the problem
@JimdalftheGrey I would agree to that also, but just like I can't tell somebody not to counteract a vote they don't like, we also can't compel somebody to post a comment explaining their vote. Both arguments work on the idea that ones' vote is their own for whatever reasons they choose
Anyway, getting side tracked. All I wanted to say was that there is no requirement/suggestion/notion/enforcement/whatever that says one must comment to explain a vote.
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> The "too chatty" flag is for comments which constitute idle discussion unrelated to the post, such as "+1 great post!" or "-1 this is wrong" or anything along those lines, unless the comment also includes an explanation
@StanShunpike It's possible it's on topic there, and it's definitely on topic here. I would expect you'd get a more physics answer here and a more "music theory" type answer there
Maybe the physics here will say it doesn't matter and the question on Music.SE would say it has something to do with making it easier to play or something
@tpg2114 Yeah, that's what I was thinking. They often have technique questions there and I just thought someone might be an experienced keyboard player and might have comments to make about other instruments as well using similar technique
..... I think most of them would agree only because most believe both exist anyway. I don't think one requires the other. I think there are ways of having QG without magnetic monopoles
@NeuroFuzzy That pole shift is going to happen any day now and wipe out mankind. But man, we could totally charge up our flashlights in the 10 seconds while the pole is flipping!
Unfortunately, this guy was actually seriously crazy and ended up taking his own life shortly before he thought the pole shift would happen (like most people who believe end-of-days things, he kept making predictions and they didn't happen so he grew more frantic)
There is no global counter-balance power with those kinds of ambitions and a national fervor to be better than said counter-balance for us to be at all dedicated to it
It's really weird actually. By like 1942 Albert Einstein is well known enough they make jokes on the show about him. And by 1948 all the radioshows are making references to all sorts of sciency sounding things involving atomic weapons
I have a long microchannel where flows some water. The reynolds number is much smaller than one. Within the structure of this microchannel there is a big defect. It looks like a bump of size approximately 20 micrometer and the microchannel's width and height are 100 micrometer.
My question is t...
Usually, sure. The point is this: I agree that one can make it seem reasonable, but I disagree that you can really derive anything deep about actions from path integrals.
So I think it's not good to conceptualize the path integral as the foundation for the action principle
I think it is more appropriate to say that it is the most powerful application of the action principle.
@Danu One may derive $$Z=\int DqDp\,\exp\left(i\int[ \dot qp-H]dt\right)$$ without any assumptions on the Hamiltonian. Then we make the standard choice $$H=\frac{p^2}{2m}+V(q)$$ and obtain the path integral once we integrate out the momentum
@0celo7 I don't view the Hamiltonian picture as having the same depth as the Lagrangian because of the aforementioned problem with breaking the natural symmetry.
What is fact is that given the path integral, we can derive the principle of least action. Given however just the principle of least action, we cannot derive the path integral.
I'm confused about Hamilton's equations vs the Euler-Lagrange equation and what exactly the definition is for an equation of motion.
Hamilton has to equations one for \dot{q} and one for \dot{p}
These are seemingly separate equations.
Why is there only one Euler-Lagrange equation?
I don't think I understand what an equation of motion is. Is it something that fully describes the position and velocity of the system? If so, how does the way EL does this differ from the Hamiltonian and why does this lead to two sets of equations for Hamilton but only one equation for EL?
Not well versed enough. I feel comfortable with my calc obviously. I tried to study ODEs but I couldn't find a book at my skill level. I found one too hard and one too easy. No I wasn't aware of that fact. That's probably the problem.
Pick up a book on electrical engineering. They hammer through all the practicalities of ODE systems, Laplace, Z and Fourier transforms etc. with well-motivated examples.
Now if you want the math background, then you should look up how matrix exponentiation works (the Jacobi irreducible form stuff, can't remember, too long ago, I can look up book recommendations if you're interested, though)
Now that I look through the contents on Amazon it looks different. I'm quite sure of the author; Maybe he's written more books. I'll Google a bit and get back to you if I find anything.
Yes, I used that book, but obviously not the 2012 edition (this latter book with almost the same title does look more familiar). I'm talking about stuff like 10 years ago or so.
Probably any book on EE should do (or automation/control engineering, although their approach is a tad different), I guess all of them go through this stuff. Take a course on Coursera or edX (although they may be too elementary).
No problem. I'm quite surprised that you seem to be trying to learn QFT and have skipped Lagrangian/Hamiltonian mechanics. Not that you should listen to me, the "deepest" physics I ever learned was introductory QFT.
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I have a long microchannel where flows some water. The reynolds number is much smaller than one. Within the structure of this microchannel there is a big defect. It looks like a bump of size approximately 20 micrometer and the microchannel's width and height are 100 micrometer.
My question is t...
