Date: Mon, 18 Aug 2003 13:59:14 -0500
Subject: Re: (urth) chems on Urth and a FTL Whorl
From: Michael Buice 


On Monday, August 18, 2003, at 01:05  PM, James Wynn wrote:

> Crush seeks clarification:
> Okay. Are ya'll saying that a generational ship *would* be required 
> for FTL
> travel?
>

Completely orthogonal question.  I'm saying that with sufficient 
technology to deliver large amounts of power, the generational starship 
is no longer a realistic story.  Although it will seem as if 30 years 
have passed to any proverbial "Typhon" back on Urth, the ship can 
travel such that the entire trip takes as few as a couple of seconds to 
the passengers, acceleration and all.  This is essentially a 
combination of time dilation and Lorentz contraction (and needs a 
geodesically complete space-time, but nevermind that).  Realistically, 
one would imagine some compromise wherein the generational starship 
makes more sense and is essentially a big rock traveling at constant 
velocity through space, not fast enough that the passengers won't still 
experience a great deal of time (as the, I believe, 500 years or so 
suggested in Long Sun).

For clarity, all of this is subluminal.  Superluminal travel, as I said 
before, completely wrecks causality and should be left to fuzzy logic 
and "heavenly" Ships.  Put it another way, Tzadkiel (or whoever 
designed the Ship) would have to know more physics than I do (says the 
physics grad student).

Michael


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