Re: FTL, ether and wind

On 16 veebr, 00:44, thro...@[EMAIL PROTECTED]
 (Wayne Throop) wrote:
> : Crown-Horned Snorkack <chornedsnork...@[EMAIL PROTECTED]
>
> : If the roundtrip time between A and B by FTL is exactly zero, and
> : signals sent A to B at FTL and back B to A arrive after a finite time,
> : how do you avoid a preferred frame?
>
> By "round trip time between A and B" you mean the time to get from
> A to B and back to A?  And is this time the elapsed time, or the
> coordinate time, or what exactly?
>
> And if A and B are points, you haven't said anything about what
> frames of reference are involved (and if they are frames of referance
> you haven't said anything about where the messages go).
>
> So... I don't see how you can conclude anything at all, because your
> hypothetical is nearly meaningless as it stands.  Taking the statement
> at face value, and if we assume that you didn't leave anything out (ie,
> about swapping frames), and that A and B are points, then what you've
> stated doesn't even come close to proving there's a prefered frame,
> since you haven't attempted measurements in more than one frame.  You
can
> "avoid a prefered frame" because all your statements are compatible with
> having been done in a single (non-prefered) frame.
>
Very well.

Let us imagine that we establish back and forth FTL signalling between
Earth and Alpha Centauri.

These two are not exactly in the same inertial frame. However, the
relative speed is not relativistic.

It is relatively easy to establish that a signal exchanged at the
speed of light travels for 8,6 years return trip.

Once we establish FTL signalling, we can establish that round trip
time is exactly zero, and never negative.

Now assume we then examine signals sent FTL one way and at speed of
light the other way.

Suppose we establish that signals sent Earth to Alpha Centauri FTL and
back at the speed of light take 3,3 years, while the opposite takes
5,3 years.

Have we then observed ether wind?