[ExI] BBC Faster Than The Speed Of Light

[david]

On Wed, 26 Oct 2011 09:27:56 -0700 (PDT)
john clark <jonkc at bellsouth.net> wrote:

> On Tue, 10/25/11, Tomaz Kristan <protokol2020 at gmail.com> wrote:
> "I don't think, that there is a time travel. Einstein's theory is
> probably too damaged, that the reasoning along those lines
> "relativity may permit the time travel" is any good." If things
> really do go faster than light it's going to be difficult to forbid
> time travel because any theory that replaces Einstein is still going
> to have to deal with time dilation because that has been confirmed
> many times in the lab, the fact that observers moving in opposite
> directions close to the speed of light will see each others clock as
> running slow. Maybe somebody can figure out a way to allow faster
> than light but not time travel but I don't know of a way, except
> maybe a parallel world or something of that sort.
> 
> You and I start out in the same reference frame, we shake hands and
> synchronize our clocks and head to our respective spaceships. Soon we
> are moving in opposite directions at a substantial fraction of the
> speed of light. I have a Neutrino FTL radio that can send messages
> almost instantly regardless of distance, so at 3PM by my clock I send
> you a message "why did the chicken cross the road?". With my
> telescope I see you receive my message and note that your clock says
> 2PM when you do. So you get my message and look at your clock and see
> it says 2PM and you send me a reply, and when you do that you also
> look at me with your telescope and see that when I receive your
> message my clock says 1 PM. So at 1PM by my clock I receive the
> answer to my message "to get to the other side"; 2 hours before I
> sent the question I receive the answer. If our radios can only send
> signals at the speed of light or less this can not happen, I can't
> get an answer before I ask a question, but with anything faster than
> light it seems that you could. And that would mean we live in a very
> crazy world.
> 
>  John K Clark


Is it just me, or is there a hole in that argument?
If you are looking at him through a normal telescope, you are looking at
old light. Regardless of the time on the clock you won't see him get
the message until after you have sent it. If you are watching
through some instant FTL "telescope", you will be able to see him get
the message, then answer it, then you instantly get the response. Still
no time travel.  What am I missing?

As far as I can see, all the arguments for time travel involve the 
assumption that there is no simultaneity between relativistic
observers , but FTL communications would break that assumption.

-David