Re: starship-design: Quantum Gravity

[Zenon Kulpa <zkulpa@zmit1.ippt.gov.pl>]

> From: kyle <stk@sunherald.infi.net>
> 
> Zenon Kulpa wrote:
> > 
> > > From: "L. Parker" <lparker@cacaphony.net>
> > >
> > > I apologize if this is old news to anybody, but it sounds interesting
> > > since it relates (slightly) to this group's objective -
> > >
> > > [...]
> > >
> > > The idea that space and time may not be continuous but are built,
> > > like matter, from very tiny "atomic building blocks" is not new - 
> > > it was proposed previously by Roger Penrose, of Oxford University  
> > > and Penn State,and other physicists and mathematicians.
> > > The work of Rovelli and Smolin is, however, the first to show 
> > > that these discrete structures are required
> > > by the laws of quantum mechanics and relativity theory.
> > >
> > > [...]
> > >
> > If that proves to be true (whatever "true" exactly means),
> > it will relate to our objective quite significantly.
> 
> Quite true.
> 
> > Namely, it will mean that our Universe is like a 3(or more)-D
> > cellular automaton (just like a giant version of Conway's game "Life"),
> > which in turn will mean that FTL is really impossible
> > (and explain why - you cannot shift bits in your computer
> > faster than one tick of your master clock...).
> 
> The universe has no "clock" as far as we know. Besides, giving structure
> to the fabric of space would only strenghten FTL (Try walking in a
> vacuum). It gives you something to warp (Alcubierre's theory),
> somethingto push against (the Aether hypothesis), and alot of energy.
> Lee Parker is right though: it could be used badly. So lets use it for
> good (FTL Propulsion), not planet bombs.
>  
Clock or no clock, if time is quantized, it means no action 
can take less time than the quantum.
Then, if space is quantized, it means that the elementary move 
in space cannot go farther than to some space cell "adjacent"
in space to the given one. Unless we allow all space cells
to be adjacent to all the other (not very interesting case), 
it means that there MUST be the limit speed, and that it is equal 
to the distance of adjacent cells (in the simplest case,
like in most cellular automata used, it means one space quantum) 
divided by the time quantum.

-- Zenon