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To: Physicist
As for gravity, what this result shows is that Einstein's nearly 100-year-old theory of gravity still works perfectly well. Some people thought that certain discrepancies in astrophysical measurements were showing us that Einstein's theory was wrong, but it turns out that the matter isn't what (or where!) we thought it was. The theory was making the correct predictions all along.

My questions on gravity are not related to what it is or how to measure it. It is related to how it manifests it's self.

What sort of energy is the field attraction comprised of, and how can we manipulate it and by doing so, create it artificially.

I know the theory, and I don't pretend to understand them as it is not my field, but I have never met anyone who claims to know everything about gravity. If that were the case, why are we still using rocket propulsion and making a bird that has to fall out of orbit and endure reentry heat to land like a jumbo jet.

This is what my questions are.

So are you saying we know this!

68 posted on 08/21/2006 10:54:11 PM PDT by Cold Heat
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To: Cold Heat
What sort of energy is the field attraction comprised of, and how can we manipulate it and by doing so, create it artificially.

Gravity is the curvature of spacetime. One of the consequences of this is that the dipole moment of the field is constrained to be zero. This poses a problem for gravitational engineering: all of our electromagnetic technology exploits the electromagnetic dipole interaction, but while there are positive and negative charges, there is only positive mass and energy. (Even anti-matter has positive mass.)

So you won't find anti-gravity, artificial gravity gravitational wave communicators, or the like. The field just doesn't work that way.

I know the theory, and I don't pretend to understand them as it is not my field, but I have never met anyone who claims to know everything about gravity. If that were the case, why are we still using rocket propulsion and making a bird that has to fall out of orbit and endure reentry heat to land like a jumbo jet.

Whatever the next theory of gravity has in store for us, it can't repeal the conservation of momentum and energy. We use rockets because, in order to accelerate, you have to have something to push against (conservation of momentum). Things heat up on reentry because the orbital energy has to go someplace (conservation of energy).

73 posted on 08/22/2006 3:29:16 AM PDT by Physicist
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To: Cold Heat
I have never met anyone who claims to know everything about gravity. If that were the case, why are we still using rocket propulsion and making a bird that has to fall out of orbit and endure reentry heat to land like a jumbo jet.

You are showing an inability to distinguish physics from engineering. The theory of gravity only tells us what forces that rocket will experience. Building a vehicle that is strong enough to overcome those forces is not physics. That is engineering. Therefore: if physicists begin to understand gravity even better than we already do that will have no effect on rocket construction unless we move into some fictional star trek world with anti-grav devices.
81 posted on 08/22/2006 9:10:46 AM PDT by newguy357
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