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Veritasium -- How Special Relativity Makes Magnets Work.
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aetherist:

--- Quote from: dunkemhigh on April 17, 2022, 04:43:22 pm ---
--- Quote --- then an aetherist would say that the string would break, koz the 2 spaceships & the string all length contract
--- End quote ---
Really? My simplistic understanding is that for speed of light to remain constant, for the observer in the static reference the spaceships (and string) must appear to contract, otherwise light in the moving reference would either be slower in the moving reference or seem to be faster than the speed of light from the static reference. The contraction allows the speed of light to be constant regardless of reference.

But then it also follows that the distance between spaceships must also appear to contract, otherwise light passing from one ship to the other would seem to slow in the moving reference. Alternatively, if it remained c in the moving reference it would seem to be faster than c in the static reference. Thus the space contraction.

So the space contracts exactly the same as the string, and the string doesn't sag or break.

I think your problem with this is that you apply contraction (and similar) to physical entities rather than the reference in which they reside.

Of course, I am not a physicist nor a scientist in any shape or form, so I could be as massively wrong about this as you. Happy to be put right by someone in the know.
--- End quote ---

U are talking bout the silly Einsteinian solution, which is Bell's spaceship paradox. I was talking bout the likely aetherian solution.
https://en.wikipedia.org/wiki/Bell%27s_spaceship_paradox
Bell's spaceship paradox is a thought experiment in special relativity. It was designed by E. Dewan and M. Beran in 1959[1] and became more widely known when J. S. Bell included a modified version.[2] A delicate thread hangs between two spaceships. They start accelerating simultaneously and equally as measured in the inertial frame S, thus having the same velocity at all times as viewed from S. Therefore, they are all subject to the same Lorentz contraction, so the entire assembly seems to be equally contracted in the S frame with respect to the length at the start. At first sight, it might appear that the thread will not break during acceleration.

This argument, however, is incorrect as shown by Dewan and Beran and Bell.[1][2] The distance between the spaceships does not undergo Lorentz contraction with respect to the distance at the start, because in S, it is effectively defined to remain the same, due to the equal and simultaneous acceleration of both spaceships in S. It also turns out that the rest length between the two has increased in the frames in which they are momentarily at rest (S′), because the accelerations of the spaceships are not simultaneous here due to relativity of simultaneity. The thread, on the other hand, being a physical object held together by electrostatic forces, maintains the same rest length. Thus, in frame S, it must be Lorentz contracted, which result can also be derived when the electromagnetic fields of bodies in motion are considered. So, calculations made in both frames show that the thread will break; in S′ due to the non-simultaneous acceleration and the increasing distance between the spaceships, and in S due to length contraction of the thread.

In the following, the rest length[3] or proper length[4] of an object is its length measured in the object's rest frame. (This length corresponds to the proper distance between two events in the special case, when these events are measured simultaneously at the endpoints in the object's rest frame.[4])
PlainName:
No, I was talking about the Einstein solution. You may have been talking about the silly aetherist solution.
aetherist:

--- Quote from: dunkemhigh on April 17, 2022, 08:05:53 pm ---No, I was talking about the Einstein solution. You may have been talking about the silly aetherist solution.

--- End quote ---
Yes i was talking bout the aetherist answer. U said....
I think your problem with this is that you apply contraction (and similar) to physical entities rather than the reference in which they reside.
In aether theory contraction applies to solids, not to space, not to gas, not to liquids.
Alltho contraction applies to gas particles & liquid particles, & their containers if any.

In the case of electrons propagating along a stationary wire, aetherists say that the electrons might be individually length contracted, but the spacings tween centers is not contracted, & the gaps are then of course dilated. Hence there can be no explanation for the magnetic field around a wire that might be similar to the silly STR explanation (of this thread).

Actually, if the electrons contract & if the gaps dilate then the electrons will want to move closer together, in which case given enuff time they will, in which case the charge of the wire will grow more negative, if electrons can somehow enter the wire from the environment. In which case aether theory results in a (very weak) relativistic explanation for mmf around a current carrying wire (somewhat similar to STR theory)(but much weaker).
PlainName:
In silly aether theory, if it applies only to solids what  happens when, say, copper is melted. Or vaporized? Is a plasma solid, liquid or gas or something else, and does silly aether theory apply to that?
aetherist:

--- Quote from: dunkemhigh on April 17, 2022, 09:53:25 pm ---In silly aether theory, if it applies only to solids what  happens when, say, copper is melted. Or vaporized? Is a plasma solid, liquid or gas or something else, and does silly aether theory apply to that?
--- End quote ---
All solids are length contracted. Atoms of gas & liquid (eg melted Cu) are length contracted. But, bulk gases & bulk liquids themselves can't length contract, they just fill their container (as usual), it is their container that length contracts.
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