Gravity Creation Idea (don't assume troll)

On Fri, 04 Mar 2005 16:40:03 -0600
"Christopher M. Jones" wrote:

The only advantage this gives you is in density. In
all other aspects this scheme is dramatically more
difficult than just using a pile of matter.

Engineering efforts would be better directed at creating artificial
black holes. That way you get a dense blob of matter, a high
gravitational field, and an energy source as well.
--
Michael Smith
Network Applications
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Web Hosting | Internet Services

Greg Kuperberg wrote:
In article ,
Greg D. Moore \(Strider\) wrote:

But also, my understanding is that what one could more properly call the
"apparant" mass of the system increase. But outside the system you haven't
changed the total amount of mass and so there's no gravitional change
outside the system.


The correct statement is that the functional mass of an object depends
on your reference frame. As Henry Spencers says, it is not in any
sense an illusion. It is a lot like considering whether the "height"
of a 100-foot rod is 100 feet or 80 feet if the rod is 37 degrees from
vertical. The rod has an intristic length of 100 feet, but that is only
its functional height when it is exactly vertical.

The apparent height would be 100 * cos(angle from vertical) which would
be less than or equal to 100.

But apparent mass would be greater or equal to rest mass. Greater
without bound (depending on how close to c you get).

I can't see the "view from a different angle" model.

Coxeter talks about 4 spatial-dimensional objects in _Regular
Polytopes_. On page 119 he advises against trying to model such with
space-time. He argues Minkowski's space-time model is not Euclidean.




--
Hop David
http://clowder.net/hop/index.html

In article ,
Hop David wrote:
Greg Kuperberg wrote:
The correct statement is that the functional mass of an object depends
on your reference frame. As Henry Spencers says, it is not in any
sense an illusion. It is a lot like considering whether the "height"
of a 100-foot rod is 100 feet or 80 feet if the rod is 37 degrees from
vertical. The rod has an intristic length of 100 feet, but that is only
its functional height when it is exactly vertical.
The apparent height would be 100 * cos(angle from vertical) which would
be less than or equal to 100.

Right. You say "apparent", and I say "functional". An important point
is that in this case, as in relativity, appearance and function mean
the same thing.

But apparent mass would be greater or equal to rest mass. Greater
without bound (depending on how close to c you get).

That's right. The formulas are mathematically similar, and conceptually
similar, but not the same. The analogue of "angle" in relativity is
the rapidity phi. Instead of trig functions, you use hyperbolic trig
functions. The functional mass of a moving particle is cosh(phi) (times
its rest mass) instead of cos(phi). As you say, the cosh function is =
1 and grows without bound.

Also the velocity is v = tanh(phi) (times c). The velocity is much like
the slope in the Euclidean analogy, which is of course tan(theta), where
theta is the angle from horizontal. But whereas tangent is unbounded,
the hyperbolic tangent tanh asymptotes to 1.

Also there is the famous rapidity addition formula: If a rocket at
velocity v_1 = tanh(phi_1) emits a projective with relative velocity v_2 =
tanh(phi_2) in the same direction, the combined velocity is

v_3 = tanh(phi_1 + phi_2)

This is like adding angles when you compose two rotations.

[Coxeter] argues Minkowski's space-time model is not Euclidean.

Right, it's Minkowskian :-). But there is a good analogy between
Euclidean and Minkowskian geometry. Coxeter's point is that he wants
four- (or higher-) dimensional Euclidean geometry, not Minkowskian
geometry.
--
/\ Greg Kuperberg (UC Davis)
/ \ Home page: http://www.math.ucdavis.edu/~greg/
\ / Visit the Math ArXiv Front at http://front.math.ucdavis.edu/
\/ * All the math that's fit to e-print *

Did somebody say inertial capacitor?

"Matthew Hagston" wrote in message
nk.net...
There's an idea that's been going through my head dealing with creating
artificial gravity, before you think troll just stay with me here. It
deals
with two of Einstein's papers; the first stating as an object speed
accelerates closer towards the speed of light, it's mass increases, the
second states mass is directly related to gravity. So Take an object like
a
large super-conductive disk, inside a vacuum to reduce friction, and spin
it. If you can make it spin fast enough (up towards the speed of light)
you
should be able to create gravity with out having the real mass required.
Creating a sort of virtual mass so to speak.

I realize there must be something wrong with my logic because this seems
like such a simple solution, so I invite some criticism here.

--
Matthew Hagston
Hungates Creative Toys and Hobbies
........ http://www.hungates.com



Ok, What is it about matter that creates gravity? Especially the fact that
if you accellerate matter it's gravity potential increases.

--
Matthew Hagston