I challenge you to make the rod fall by cutting the suspending wires in zero gravity.
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Relativity paradox
- Thread starter renislaj
- Start date
I challenge you to make the rod fall by cutting the suspending wires in zero gravity.
I challenge you to make the rod fall by cutting the suspending wires in zero gravity.
There are no wires in the dumbed down scenario. Just a rod moving at constant speed toward the floor.
There are no wires in the dumbed down scenario. Just a rod moving at constant speed toward the floor.
Then open your own thread on the dumbed down scenario. Stop polluting this thread.
So you agree that the dumbed down scenario is not unphysical and is in the domain of SR?
No, I don't . It is unphysical, so you can stop trolling. Please go open your own thread, stop polluting this one.
What is unphysical about a rod moving at constant speed in zero gravity?No, I don't . It is unphysical, so you can stop trolling. Please go open your own thread, stop polluting this one.
I really don't understand what the difficulty is with the scenario. There's no point in making a thread about a flawed scenario, so I'd like to nail this down first.
In $$S''$$:
$$\begin{align}
A'' &= \left(x_A''(t''), \ y_A''(t'') \right)\\
&= \left(\frac{x_A'}{\gamma'} - Vt'', \ -ut' \right)
\end{align}$$
$$\begin{align}
B'' &= \left(x_B''(t''), \ y_A''(t'') \right) \\
&= \left(\frac{x_B'}{\gamma'} - Vt'', \ -ut' \right) \\
\end{align}$$
The angle of the rod with the x-axis at time t'' is:
$$\begin{align}
\tan(\theta'') &= \frac{y_B''(t'') - y_A''(t'')}{x_B''(t'')-x_A''(t'')} \\
&= \frac{uV\gamma' / \gamma c^2}{1 / \gamma'} \\
&= \frac{uV\gamma'^2}{\gamma c^2}
\end{align}$$
Your Thomas rotation answer is wrong, as demonstrated in (edit) [post=3062610]post 157[/post].
Like I said, based on your above calculations, I am having a hard time taking you seriously.
Which line do you disagree with?Like I said, based on your above calculations, I am having a hard time taking you seriously.
Which line do you disagree with?
You can't see? LOL.
You can't see? LOL.
If you see a mistake, I 'd be happy for you to point it out so it an be corrected.
Which line do you disagree with?
Do you want me to redline your mistakes?
one gets absurd results when trying to force the wrong formalism (SR, in this case) on a problem that requires GR in order to solve.
But you agree that in either formalism the floor of the train, like the rod, will always appear crooked to the platform observer? If yes then the train floor and the platform surface can never appear level parallel to the platform observer unless you combine frames like I think you did there? I am still confused.
Edit/ It is also my naive understanding that in SR problems any reasonably weak Gravitational Field can be sliced up into small distances and any "GR curvature" may be effectively ignored (even if initial motion of the rod is due to that field, it need not be a strong acceleration but a weak one)? Wouldn't the same "simplification" eliminating GR from consideration apply to each subsequent small slice of distances to each subsequent position traced along the path line to the floor (or platform or whatever)? I can't see why we can't do this problem like Pete wants and see what we get so I can improve my naive understandings from it.
Do you want me to redline your mistakes?
Please, point out the mistakes you see, and I'll fix them.
Edit/ It is also my naive understanding that in SR problems any reasonably weak Gravitational Field can be sliced up into small distances and any "curvature" may be effectively ignored (even if initial motion of the rod is due to that field, it need not be a strong acceleration but a weak one)? Wouldn't the same "simplification" eliminating GR from consideration apply to each subsequent small slice of distances to each subsequent position traced along the path line to the floor (or platform or whatever?).
No, it wouldn't, please stop hacking at the problem. There are enough hacks in the thread already. See what Neddy Bate tried, see what Pete is trying.
Please, point out the mistakes you see, and I'll fix them.
Move your post in another thread, dedicated to the dumbed down version and I will be more than happy to point out the mistakes in your math. Honestly, for someone so quick to point out other's mistakes, I am surprised that you have such a hard time seeing your own, they are quite obvious.
The space of SR is Euclidian, so I disagree.
This line of thinking is what makes the rod distorted in the platform frame but not in the car frame. You are doing the same exact thing as Pete is doing, stubbornly trying to apply SR to a problem that is a GR problem. GiGo.
Ok, you disagree. You and Pete are working through the math, so I'll leave you to that. If you can show mathematically that parallel-ness is transitive in SR, I'll immediately concede that I'm wrong about everything.
But in the mean time, you have yet to respond to post 151 at all. Sorry to harp on that so much, but I rather liked post 151, and it irks me a little to see you ignore it in reply after reply. Without invoking any equations from SR, post 151 shows that if the wires are cut at different times in the platform frame, the rod hits the floor at an angle in the platform frame. Could you please tell me what is wrong with that argument? Or at least acknowledge that I made it?
To be honest, I haven't double-checked yet. I mistakenly thought it would be quicker if you simply pointed out the mistake/s you found. There are also a few steps I did on paper that I didn't transcribe to tex.Move your post in another thread, dedicated to the dumbed down version and I will be more than happy to point out the mistakes in your math. Honestly, for someone so quick to point out other's mistakes, I am surprised that you have such a hard time seeing your own, they are quite obvious.
Now, before I make a new thread, you said earlier that the dumbed-down scenario is unphysical.
There's no point in making a thread about a flawed scenario, so I'd like to nail that down first.
What is unphysical about a rod moving at constant speed in zero gravity?
Ok, you disagree. You and Pete are working through the math, so I'll leave you to that. If you can show mathematically that parallel-ness is transitive in SR, I'll immediately concede that I'm wrong about everything.
It is trivial, the space (not spacetime) of SR is Euclidian. in Euclidian space, parallel-nes is a transitive property.
But in the mean time, you have yet to respond to post 151 at all.
I did, you just seem to refuse to accept the answer. As an aside, you and Pete should jointly open a separate thread dealing with the dumbed down scenario that you seem so intent on analyzing. I would like to keep this thread on the OP. Deal?
To be honest, I haven't double-checked yet I mistakenly thought it would be quicker if you simply pointed out the mistake/s you found.
I think that is telling about your outlook, you are just blind to your own mistakes, I think it would be educational if you made the effort to find them, I narrowed down the post to the lines (not one) containing the mistakes (multiple).