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And any uniform motion, including the one seen as a gravitational acceleration when standing on Earth is defined by no 'gravity' perceptible inside a 'black box'.

Did you read the pdf?

I'm trying to figure out where this gravity discussion ties in to the original question.

Maybe you didn't read the pdf JP?There you can find everything about it.

I know I'm going to get PBLA'ed for this, but aren't ....

"However, you cannot simply superimpose that reality on to a different black box, because that black box has a different reality." In a way it's the opposite actually. If you can create a 'black box scenario' in where you find an exact equivalence to what you observe otherwise then the chances are pretty good that they are the same. That's why all black boxes uniformly moving are seen as the same, no matter their speed relative each other. and that's why a constant acceleration at one G is equivalent to Earths gravity (or any gravitational field of one G). It's a minimalistic approach to 'reality' you might say.But if you meant "superimpose that (uniformly moving) reality on to a different (accelerating) black box, because that black box has a different reality." then I agree, and that's also what black boxes test, if they are the same or not (the physical laws).

Quote from: JP on 02/03/2011 01:36:20I know I'm going to get PBLA'ed for this, but aren't ....Actually, I'm not using a Newtonian model []Geodesics are all about the interaction between space-time and matter. But whatever model we choose to use, the laws of thermodynamics (until they are repealed) will still govern the energy transactions.

but what happened with that photon hitting your eye? Isn't heat, all said

But, it's definitely 'work done' in its most simple meaning.

I got my answer and everything else is crap actually what happens is that a systems internal energy is defined from a frame of reference in which the center of mass is at rest and hence adding potential energy to the system does not add to its internal energy. A steady state is established in terms of internal energy for these works performed.

Quote from: yor_on on 02/03/2011 16:20:28But, it's definitely 'work done' in its most simple meaning.Except that in general relativity, two observers don't necessarily agree on gravitational work and gravitational energy conservation, so there is no general work-energy theorem. Energy conservation doesn't necessarily hold in general relativity if you try to account for gravitational energy. That's why it's so confusing to try to get the GR picture to agree with conservation of gravitational energy--it doesn't in all cases.

Quote from: JP on 02/03/2011 20:13:49Quote from: yor_on on 02/03/2011 16:20:28But, it's definitely 'work done' in its most simple meaning.Except that in general relativity, two observers don't necessarily agree on gravitational work and gravitational energy conservation, so there is no general work-energy theorem. Energy conservation doesn't necessarily hold in general relativity if you try to account for gravitational energy. That's why it's so confusing to try to get the GR picture to agree with conservation of gravitational energy--it doesn't in all cases. JP - Is that because the observers will disagree about distance, force, distance and force, or something else?

But I can't speak of any 'work' being done by gravity,

Nooo It does no work.. I'm sure about that.

So, I'll still be able to prove that gravity did work, or at least produced equivalent work.