OT Faster than light was: Hollywood OS wars 3316

In comp.os.linux.advocacy, Aragorn wrote on Mon, 06 Mar 2006 17:57:00 GMT

I said "Newton" for a reason, but you're right. Lightspeed travel even for a particle is impossible, as far as we know given current theory. Applying 1-2 m c^2 energy to said particle might get it to 0.74 c or thereabouts (the gamma factor would be 1.5).

Uh...no. A ship traveling at near-lightspeed would be able to shoot beams of light forward at lightspeed and would suffer no ill effects (especially since virtual photons transmit charge and magnetic interactions anyway). Anyone intercepting those beams would also see them moving at lightspeed, though the wavelength and intensity would not be what they expect.

Constant lightspeed for all observers (moving or no) is a prime tenet of special relativity.

That would be easy enough. All one really needs to do is to have the relationship

For convenience, set c = 1 therefore

If v = sin(theta), then sqrt(1-v^2) = cos(theta) and therefore

So go faster than about 0.7071c and one can get somewhere apparently faster than light. (The truth will come out when one eventually comes back; if one goes to say Sirius at "apparent lightspeed", then comes back, the ship time is 16 years but the Earth-based time is about 22.6 years.)

Ships don't move within their *own* coordinate systems. :-) I know very little about this drive, though, beyond its existence.

Hmm....one wonders if Alcubierre ever read James Blish. :-)

I do not believe that the universe is expanding faster than lightspeed; the corrective factor is sqrt(1-v-c)-sqrt(1+v-c) which can take any value between 0 and infinity (although for and I for one would have to study the problem further.

Those are minimal, on the order of at the very most 10^-9. GPS satellites in particular are sped up by a factor of (1 + 4.4647*10^-10).

One of the more interesting problems in a conventional sublight system would be that, if the ship's going fast enough, the 1 particle per cubic centimeter or so of matter will irradiate the ship (or, if sufficiently chunked, impact it!). The radiation hazard is very real in space, though I'm not sure how much of an actual problem it would be outside of the Oort cloud, if one can dodge the chunks.

Wormholes would have to be *huge*. A standard calculation apparently in astrophysics clbutt puts the boundary of a useful wormhole (in other words, one wide enough to shove a human through -- or maybe just something 1 meter wide through; I've forgotten) beyond Pluto. (The energy to create one would be extremely huge as well, presumably.)

Deep Space 1. Nice little drive but it would take next to forever to accelerate anything to near-lightspeed with it. :-)

Well, the main problem is that one has to get out of the atmosphere first.

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