Re: SETI: SAT Spread Spectrum indistinguishable from normal star?

Lee Daniel Crocker (
Tue, 28 Oct 1997 09:48:18 -0800 (PST)

> > Also: If the clock is being referenced to say, a pulsar that all can
> > observe, then such a compression scheme is possible for widespread use,
> > eh?
> Something *approximating* it, maybe. Another problem is that (I think) you
> have to be able to _resolve_ time to the granularity of the symbol rate.
> Methinks there's another engineering limit there. You'd have to know
> your position and velocity relative to the pulsar in order to correct for
> Lorentz-Fitzgerald effects; h-bar <uncertainty> = delta p x delta v,
> right? I am not sure whether all these limits converge, but my gut and
> vague memories say they do.

Isn't it even simpler than that? If we're talking about FTL communication
here, then by definition the message is received outside the light cone
of the pulsar with respect to the sender, and "simultaneity" is undefined
and can't be used to clock the signal.

Lee Daniel Crocker <> <>
"All inventions or works of authorship original to me, herein and past,
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