sci.physics.particle

On Feb 25, 11:33 am, oldc...@webtv.net (oldcoot) wrote:
> > Space isn't a vacuum, it's absolutely > chuck full of...
>
> That's why the word was bracketed in " " marks - to express the
> absurdity of the term "vacuum".
>
> > If doing better than 'c' is what it takes, > then so be it.
>
> "Doing better than c" is de facto superluminal. While the traveling warp
> node is indeed superluminal to our stationary frame, GR is not violated
> locally inside the node, as Alcubierre's model illustrates.
>
> > However, what about > putting on the
> brakes?
>
> You'd simply drop out of hyperdrive by collapsing the warp node. It'd be
> analogous to decelerating a supercavitating torpedo by collapsing the
> cavitation bubble. Try a Google under 'Supercavitating Torpedo' for some
> interesting stuff. It's a great analogy.
>
> > ...and what about > keeping in radio
>
> contact with our > mission that's exiting away from us at> better than 'c' might require a trail of > microwave/laser
>
> transponders (at least > one transponder for each 0.1'c').
>
> Remember that when running in hyperdrive, there is *no* time dilation.
> Your on-board chronometer runs at the same rate as clocks at home.
> The concept of maintaining "radio contact" via
> repeater stations etc. becomes entirely moot. Radio as we know it will
> have been relegated to the status of a jungle drum. And a real-time com
> link will be based on technologies not conceived yet.

Then pulling out of warp speed for each laser cannon quantum/FM packet
of to/from data seems doable, especially if those efforts can be
accommodated by the deployed transponders that can't sustain much
better than 0.1'c' per blueshift segment, so that the mother-ship or
pilot probe itself need not slow down.

>
> > Remember, once getting past the interstellar L1, it's a gravity pull
> that'll help get our craft or whatever probe(s) as going faster and
> faster until we see that we're zipping entirely past Sirius.
>
> You're still under the Newtonian paradigm and thinkin' the sub-luminal
> way. Under the old model, you'd run at 1G acceleration for half the
> distance, then at the halfway point, turn the ship around and run under
> 1G deceleration the remaning distance.. so you arrive at your
> destination at the correct speed to simply drop into orbit.
> The problem with ion drives though, they're not capable of
> anywhere near 1G accelertaion. So you would indeed have the problem of
> "putting on the brakes" at the destination. That's another reason the
> ionic idea is hairbrain in relation to interstellar travel.
> Realistically, you'd need some form of plasma-fusion drive to get any
> usable thrust for the long timespans involved.

That is not entirely true, whereas a tonne of LRn222 or of some other
highly active or even inert gas of ions as our cache could be utilized
within as little as 1000 seconds if need be. Do the Kgf=.5MV2 for an
ion exit velocity of 0.2'c' that's getting rid of one kg/sec, and as
such it doesn't look so wussy to me.

I also like the 3He/fusion alternative as a plasma thruster, though
how about using a Rn222 pumped laser cannon sort of plasma beam?

BTW, in order to save a little precious time at either end, why not
use a 2 G acceleration/deceleration process?

If we're talking of robotics, then perhaps +/- 100 G seems doable.

How much applied energy while trekking through the ISM of dark matter
and dark energy at 0.1'c' will it take per m3 or per tonne in order to
sustain that velocity?

Oddly, ion propulsion drives and of thorium reactors are entirely
doable as is, whereas your warp drive that's faster than 'c' isn't
even on the drawing boards of cutting edge technology. Am I missing
something?
. - Brad Guth