At 04:59 PM 5/31/00 -0700, you wrote:
>In a particular experiment, I program A to send a signal through B which is
>recieved by F. I also program D to, at the moment it recieves a signal
>through F, send a signal to C (via E). I then program A to abort the
>transmission through B if it recieves a signal through C. Assume that
>controller to peripheral communication costs 0 time. Let's also assume that
>data processing and code execution costs 0 time. (I'm asking for some
>imagination here!).
>
>So, A tells B to send a FTL signal to F. D, upon recieving this signal,
>tells E to send a FTL signal to C. A, upon receiving this signal (via C),
>aborts the original transmission WHICH HAS ALREADY TAKEN PLACE. Paradox
>anyone?
>
>Ian
Since when does FTL imply instantaneous? There's still a transmission
delay, otherwise, we should drop FTL and use the word instantaneous.
The assumptions you ask us to make enable the paradox. In the real world,
the comm delays and processing delays will ensure that the return message
happens safely after the first message was sent.
All I see happening here is that you are substituting a long tunnel ("delay
line") with a finite delay for actual space. The receiver and transmitter
could be sitting next to each other on a bench, or separated by light
years, it makes no difference.
Even if the transmission is instantaneous, the same rules apply. The only
way you get a paradox is to assume that the first message arrives at the
distant station far enough BEFORE it is transmitted so as to allow the
paradox.
You need a time machine, not FTL.
Chuck Kuecker
This archive was generated by hypermail 2b29 : Thu Jul 27 2000 - 14:12:20 MDT