Recent content by Sorcerer

Well done chaps!

Thanks. @Ibix . There's been some real madness on the forums about this lately, and I think it stems from people taking the iron filling example to mean much more than it actually does. I do have one question. You said "[f]ield lines are the integral curves of a vector field." Can that sentence...

Obviously in the title I mention the user that recently got banned, but the reason I do is because s/he was having some trouble accepting that a B field transforms into a mixture of E and B fields per the Lorentz transformation (and other assorted quackery), so it got me thinking about why this...

Not to get nosy and interject here, but isn't it true that if you remove all of that noise and just focus on a point particle that has mass and is at rest, the only "rest energy" left in Newtonian physics would be potential energy due to position, which can be transformed to zero with a suitable...

As an undergrad I've often heard "classical physics" used to describe physics before quantum mechanics and "classical mechanics" used to describe Newtonian mechanics. I know this is way off topic, but that's what I've heard the most and it doesn't seem as ambiguous.

Based on your other thread I realize this might not be satisfactory, so here's my attempt to clarify, and point out why the way space and time are thought of in special relativity versus Newtonian (aka Galilean) relativity are key. In Newtonian relativity, the value ##(Δd)^2 = (Δx)^2 + (Δy)^2 +...

My take: The form $$E=\frac{p^2}{2m}$$ holds, in the sense that $$E’=\frac{p’^2}{2m}$$ is also true, but ##E’ ≠ E##. That is just kinetic energy, and kinetic energy is also frame dependent in SR. Meanwhile, in Newton there is no equivalent relation that is invariant everywhere of the form...

One cool thing I saw in Reflections on Relativity (a popular online book often posted here) is that Newton's model can be described as the time aspect of GR. I know this seems tangential, but if you think about it, it has some relevance. Specifically, this section...

Minkowski diagrams are pretty much all math as far as I’m concerned. Just don’t draw little rocket ships on the diagram. But if it’s not too late you could also add some fluff to your paper by coming at it from a linear algebra perspective, because the fundamental concept investigated with time...

I was thinking about this for no particular reason and I'm suddenly having an algebra crisis. If I take $$ΔT = \frac{L}{2(c+v)} - \frac{L}{2(c-v)}$$ I do not get ##ΔT = \frac{Lvγ^2}{c^2}## out of it. I get this: $$ΔT = \frac{L}{2(c+v)} - \frac{L}{2(c-v)}$$ $$ΔT = \frac{L(c-v)}{2(c+v)(c-v)} -...

So we have an issue about two different convergence questions: one being about the infinite series as the number of terms n approaches infinity, and one talking about what happens as the value x approaches 1.Correct? In any event, the latter diverging seems pretty intuitive as you are...

Why not just derive the Lorentz transformation from the two postulates, then use proper time to get an expression for relativistic momentum, and then W = ∫(dP/dt) dx ? Seems a lot cleaner, IMHO.

Why don't you try assuming the inverse time transformation, plugging it in and the solving for whatever you're calling x? I was playing around with doing this and got something vaguely similar to what it's supposed to look like, but with your notation using ##ΔT## to equal two different things...

Here is the equation for magnetic flux (the simplest version): $$Φ_B = BS cos θ $$ where B is the magnitude of the magnetic field and S is the area of the surface, and θ is the angle between the field lines and the normal to S. Tell me, where is the symbol representing velocity? Note: you...

There is not cause that physics can answer. It's just the way the universe is. But maybe a reason can be given for you? What follows is a overly simplistic historical retracing of some of the events and reasoning that led to this realization, and hopefully some understanding. (1) Galileo...