How Time Passes Differently for Twins Traveling at Light Speed

[Ich]

Ich: The LT are correct if the postulates are correct since they follow straightaway - but other postulates like those posed by Selleri recogonize two way isotropy (round trip velocity of c constant) but they do not share Einstein's postulate of one way isotrophy - consequently Selleri transforms predict the same time dilation in terms of the correctness of the interval, but they do not include the vx/c^2 factor. Ironically, because of the methodology used in the physical experiments that seek to measure time dilation, this term doesn't get measured (no clock displacement in the relatively moving frame). So, my above statement is based upon the correctness of the LT, which is why I prefaced it with "In Theory"

So those transforms that you prefer are just the LT without vx/c^2?

 

[jdavel]

yogi,

"...consequently Selleri transforms predict the same time dilation in terms of the correctness of the interval, but they do not include the vx/c^2 factor..."

This is great!

I Googled 'Selleri transforms' and the first hit I tried sent me to one of your posts on physicsforums!

So I tried the next one. That took me to another one of your posts!

At that point I was laughing too hard to try any of the others.

 

[yogi]

Well - what can I say. I assure you selleri transforms exist independent of yogi and google. Below I will give you a link

http://redshift.vif.com/JournalFiles/V11NO1PDF/V11N1SEL.pdf.

 

[jdavel]

JesseM and yogi,

Sorry about not finishing this; I got side tracked. Let's try it once more.

This time, to avoid confusion about English terminology, let's START by just labeling events (E1, E2...) and giving their coordinates. Then make sure that all events that either of you think are relevant have been included Then make sure we agree that (according to the Lorentz transforms) the coordinates are correct. Only then do we discuss in English what the events correspond to and what their coordinates are telling us.

Terminology:

Two frames S and S' with S' moving at v relative to S
Y = gamma
c2 = c*c
The coordinates of an event En are xn, tn, xn', tn'

So (no earth, no stars, no clocks, no english at all; just some events and their coordinates!)

En...xn...tn...xn'...tn'


E1...0...0...0...0

E2...L...Lv/c2...L/Y...0

E3...L...L/v...0...(L/v)/Y


Are these all the events we need?

Are the coordinates all correct?

 

[JesseM]

JesseM and yogi,

Sorry about not finishing this; I got side tracked. Let's try it once more.

This time, to avoid confusion about English terminology, let's START by just labeling events (E1, E2...) and giving their coordinates. Then make sure that all events that either of you think are relevant have been included Then make sure we agree that (according to the Lorentz transforms) the coordinates are correct. Only then do we discuss in English what the events correspond to and what their coordinates are telling us.

Terminology:

Two frames S and S' with S' moving at v relative to S
Y = gamma
c2 = c*c
The coordinates of an event En are xn, tn, xn', tn'

So (no earth, no stars, no clocks, no english at all; just some events and their coordinates!)

En...xn...tn...xn'...tn'


E1...0...0...0...0

E2...L...Lv/c2...L/Y...0

E3...L...L/v...0...(L/v)/Y


Are these all the events we need?

If you don't discuss what these events mean in english, and what you want to find in english, then we can't really say whether these are all the events you "need." (what do you need them for?) But if we say as before that there are two clocks A1 and A2 at rest in S and synchronized in S, and another clock B moving at v relative to them (at rest in S'), and B first passes A1 (with both reading 0 at that moment) and then passes A2, then these three events will tell you how much time elapses on both B and A2 between the moment when B passes A1 and the moment when B passes A2, in the S' frame. If you want to know how much time elapses on both clocks between the times of these events in the S frame, then instead of E2 you need this event:

E2a...L...0...YL...-YLv/C^2

Since yogi now says he doesn't even agree with the Lorentz transform, I don't see him agreeing with the events you chose.

 

[jdavel]

...Since yogi now says he doesn't even agree with the Lorentz transform, I don't see him agreeing with the events you chose.

JesseM,

Well, he's free to pick any additional events he wants. But more to the point, I don't think yogi is interested in discussing relativity with event coordinates, intervals, etc. He wants to discuss things like "time slippage", "length contraction", "time dilation" and "objective differences". They give him the wiggle room he needs to escape whenever you try to pin him down on one of his errors.