Re: The problem of relativistic synchronisation

Am Sonntag000001, 01.09.2024 um 12:18 schrieb Richard Hachel:

Le 01/09/2024 à 08:27, Thomas Heger a écrit :

Am Samstag000031, 31.08.2024 um 09:05 schrieb Richard Hachel:
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This is the set of all places, which can use the same kind of clocks.
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They do not need to show the same time, however, but need to tick at the same rate.

 This is called a relativistic reference frame.
 All clocks there have the same chronotropy: that is to say, they turn at the same speed.
 I do not use the term reference frame like physicists, because the term reference frame is an abstract invention, a verbal nothing, a pure nothingness due to the fact that each point of the reference frame has its own clock, certainly isochronotropic with respect to neighboring clocks, which will never "absolutely" mark the same time as the neighboring time on which it will always advance by t=x/c (and vice versa) during a universal synchronization of type M.
 

I use the observation, that clocks around the Earth surface tick at the same rate, while they don't tick at the same rate at different altitudes.
This is actually a continuus effect, which extends 'outwards' in space.
In space we see past events only and the further away the longer ago.
The future is not visible, mainly because future comes later than what we call 'now'.
This 'now' is called 'hyperplane of the present' in relativity lingo.
In a typical spacetime diagram it is a horizontal plane, while the axis of time points up vertically.
This axis of time is surrounded by our own futur light cone.
Now we have a consistent picture, which describes, what we mean by 'now'.
To reach such events now along the hyperplane of the present from our own position is, of course, not possible.
But we could assume something hypothetical, which could and moves with infinite velocity.
Since light isn't THAT fast (though fast), we need to compensate the difference 'by hand'.
This is simple: since our signals actually move along our future light cone, we need to subtract the delay and would reach a point on that hyperplane of the present.
If we receive a signal, we would need to add the delay, because that would 'raise' a point from our own past light-cone to that hyperplane.
TH