- #36
PeterDonis
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The switching was in defining ##x = v^2## and ##a = v'^2## instead of the other way around.Hak said:Thank you. Yes, I wrote ##L' (v'^2)## instead of ##L'(v^2)##, right?
The switching was in defining ##x = v^2## and ##a = v'^2## instead of the other way around.Hak said:Thank you. Yes, I wrote ##L' (v'^2)## instead of ##L'(v^2)##, right?
PeterDonis said:That's because they're not fine if you have already chosen the unprimed reference frame.
I guess I didn't really understand. So you can change the frame of reference, but you can't reverse ##x## and ##a##, right?PeterDonis said:Obviously not, because in post #21 you switched reference frames (you didn't realize that's what you were doing when you said ##x = v^2##, ##a = v'^2##, but it was).
I'm not sure what more I can say. When you define ##x = v'^2##, ##a = v^2##, you are choosing the unprimed frame. That's just a fact. There is no "explanation" for it. So if you say ##x = v^2##, ##a = v'^2##, that is inconsistent with choosing the unprimed frame. What more is there to say?Hak said:I would be grateful if you could explain it again in a way that I can understand it.
Wrong. Reversing ##x## and ##a## is changing the frame of reference. But then you have to start the whole analysis over from the beginning. You can't just reverse them in one equation, that was obtained by a series of approximations that assumed you were using the unprimed frame.Hak said:So you can change the frame of reference, but you can't reverse ##x## and ##a##, right?
I did not understand what calculations I should have done to choose the primed frame of reference. Should I change all the calculations in the unfolding to do that? Thank you very much.PeterDonis said:When you define ##x = v'^2##, ##a = v^2##, you are choosing the unprimed frame. That's just a fact. There is no "explanation" for it. So if you say ##x = v^2##, ##a = v'^2##, that is inconsistent with choosing the unprimed frame. What more is there to say?
See post #40.Hak said:I did not understand what calculations I should have done to choose the primed frame of reference. Should I change all the calculations in the unfolding to do that?
You're welcome!Hak said:@PeterDonis Thank you so much for everything, I think I understand. You really gave me a great amount of help. Thank you again.