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Re: starship-design: FTL and current physics

Kyle R. Mcallister wrote:


>Alcubierre DID NOT say that the amount of exotic matter had to be larger
>than the universe.

That's right, because he never bothered to calculate how much would be
needed.  He didn't even determine any way to create the metric, other
than the obvious part that it would somehow require negative energy

Michael Pfenning and L.H. Ford did bother to calculate how much
would be required in their paper "The unphysical nature of 'Warp Drive'".

>(Even if so, no problem when you have 10^94g/cm of
>negative energy density every where...don't ask. You don't want to

We probably don't.

>I would like to know why assymetrical inertia is physically impossible.
>I don't see why it would be. And for God's sake, don't send the
>resposnse as a nasty comment.

Because of conservation of momentum, which everything we have
observed so far and know about physics so far conforms to.  At
the very least, it applies to every sort of mechanism involving
moving weights around.

Maybe conservation of momentum isn't valid.  Everything we've
observed so far conforms to it, though.

>Have any of you stopped to think about something just a bit possible: we
>know less than there is to know?

Actually, every scientist is keenly aware of how what we don't know
dwarfs what we do know.  That doesn't mean we don't know anything.

>Newton works at low speed. He flunks at
>high speed, and Einstein takes over. Who is to say that it ends there?

Maybe it doesn't "end there".  But maybe it does.  One thing's for
sure, we can't design a starship around principles which have yet
to even be observed, much less understood.

Everything we've observed seems to conform with general relativity as
well as precisely as we can detect things, and we _have_ really pushed
the boundaries right up next to the speed of light (with particle
accelerators).  Relativity is one of the most experimentally tested
theories ever, tested in many different ways and by countless skeptics.

That's a lot more than could be said of Newtonian motion, which
astronomers observed did not predict the motion of planets
exactly right (in real life, planetary orbits precess).  Even at
these "low" speeds, Newtonian classical mechanics was known to
be flawed.
    _____     Isaac Kuo kuo@bit.csc.lsu.edu http://www.csc.lsu.edu/~kuo
/___________\ "Mari-san...  Yokatta...
\=\)-----(/=/  ...Yokatta go-buji de..." - Karigari Hiroshi