Re: Langevin's paradox again

Den 14.07.2024 20:31, skrev Richard Hachel:

Le 14/07/2024 à 19:07, "Paul.B.Andersen" a écrit :

Den 14.07.2024 04:02, skrev Richard Hachel:

 

If Stella was accelerating longitudinally, the speed would change
and γ would be a function  of time, so the acceleration would
obviously affect Stella's proper time.

 Absolutely not.
 Proper time is an invariant.

Good grief!
You are calling yourself "the greatest physicist
in the universe" and don't know what "invariant" means!
Yes, proper time is invariant because it is independent of
frames of reference. A clock shows what it show.
But of course the proper time will change.
Stella's proper time (shown by her clock) increases with
a second every second.
If Stella leave Terrence with the initial speed 0.8c
and accelerates toward Terrence (brakes) with a constant
proper acceleration, her speed in Terrence rest frame will
diminish with time to zero, and then increase until she
passes (hits?) Terrence with the speed 0.8c.
Everybody but complete morons will understand that the acceleration
will affect Stella's proper time when she is back at Terrence.
It will be different from the case where Stella's speed
is constant 0.8c, even if the durations of the journeys are
equal on Terrence's clock.
So if Stella accelerates longitudinally, her proper time
will end up different from the case when she only accelerates
transversally.
The transverse acceleration doesn't affect Stella's proper time,
the longitudinally acceleration does.

 Acceleration no affects anything, only improper time because speed is différent.
Acceleration is measured in the reference frame of the accelerating object, and as the external space that accelerates relative to it.
It is therefore both completely inactive in proper time, remains constant in this frame of reference, and becomes relative if it is measured in the observing frame of reference.
 R.H.

You don't make much sense, but you _are_ funny! (sometimes) :-D
--
Paul
https://paulba.no/