🚀 go-pugleaf

Julio Chou wrote:
> 
> oooooohh, the Wormholes, where warping around regions of the universe
> would be possible!!! These things would so cool to have around. But too
> ...
> Erik Didrik Heim wrote:
> > ...
> > I use them on a daily bases and I really get around.
> > Oh what a century ! What comes next.
> > ...
> > > Ragu wrote:
> > > >
> > > > i'm no rocket scientist, but i read some crazy article in a science
> > > > magazine about how someday, people would use black holes for time travel.
> > > > ...
> > >   I think it's bull.
> > >
> > >  If a black hole could accelerate an object to near light speed or to
> > > light speed, what would make one believe that the attractor would
> > > release you. If you had enough energy or force to apply for a release,
> > > you wouldn't need the attractor (black hole). I think the only way would
> > > be to continue into and be ejected from the attractor as happens with
> > > some black holes.  By the way this is for all replying to this thread.
> > > Please edit the 'Newsgroups' field as you post or reply be e-mail.
> > >
> > > Top Quark...The Missing Particle...

Actually, the problem reduces to a simple head on elastic collision
where the only force acting on either the black hole or the space ship
is good old gravity (much like the trick used to accelerate Voyager
outside the solar system by colliding it with Jupiter (note: when I say
collide I do NOT necessarily mean physical contact, the physics are the
same, though)). You could very easily calculate a trajectory that
brought you in close to the black hole and then catapulted you outward
without any thrust required from your spaceship at all (you have to
assume particle models here (or at least I do) so it may pose some
problems in reality). Thus from your standard physics text book you get
the velocity of the black hole after the collision at -v(i)+2v(cm)
(negative initial velocity plus 2 times the velocity of the center of
mass of the system), which since the black hole is much more massive
than our spaceship is just it's initial velocity. The velocity of the
spaceship becomes also, -v(i)+2v(cm), in other words,  it can only
change it's velocity by twice that of the black hole. This would
accelerate the space ship as the signs of its velocity and that of the
black hole would necessarily be opposite with respect to the center of
mass. BUT, and this is the important but, the relative velocity of the
space ship and the black hole CANNOT exceed the speed of light going in,
so no numbers put into this equation could yeild a relative velocity
greater than that speed. Yippee, Einstein was right. But this is a
standard way to pick up velocity by stealing linear momentum from huge
masses that don't really need all of theirs.