J.C.MacSwell

I Wonder if TWP is actually helping Elegant sales?

No, you're all wrong, but I'm too busy to explain. But take it from me, you're all wrong. (even the original poster who was just asking, he's wrong also in a different way but I doubt you'd understand if I told you why) Glad I could help.

Correct, but drag on the moon speeds it up not down, though I have heard the moon should eventually escape (on a thread here, can't remember which one or why it escapes)

Oh good, more greenhouse gas. Gotta love carbon...cough...cough.

Good, I think that was Spyman's point also. More on this later (anyone know definitively what GR would say on this?) but I like your view of the expansion or contraction as nothing actually moving (local movement aside) which is also how I picture it from an "outside" POV. This brings us back toward my original question about the momentum of the expansion. Since "nothing is actually moving" what keeps the expansion going? What tells space to keep expanding at the same rate? Assuming gravity can only change the rate incrementally over time from the present rate the main factor that determines tomorrows rate is today's rate, the present "momentum" of the expansion.

It's getting closer because it is yielding to gravity. I think I see what you are getting at with regards to direction though by your "nothing is moving at all" comment. You are only considering the effects of nondirectional yielding to gravity to affect (or coincide with) a shrinking of space. (Am I reading you correctly?)

Then why would space collapse when all the stuff gets moved together? I think GR predicts this whereas Newtonian physics does not. It is like the potential energy of mass displacements supports what space "is". So the one small ball drop (and Earth "dropping" immeasurably toward the ball) is one small "tuck" (much much smaller than the immeasurable Earth displacement) in the fabric of space.

Newtonian/Euclidean this is obviously right.

If the sum of all masses collapsing gravitationally add up to a collapse of space, would not a small insignificant gravitational "collapse" coincide with an immeasurable reduction in space. (relative to if the event had not happened and all other things being equal) Edit: and if this is correct, what does it say about space? Gravity seems to balance out in the 3 apparent space dimensions and all mass seems to "escape" the insignificant dropping of a ball so I'm sorry but I am still missing your point. Don't give up on me though!

Calmer and less paranoid? Right where I'm sitting.

I think you're right. Care to elaborate?

I think you missed a few!

Because if you dropped all of the balls in the universe you would have a big crunch.

Yes, counter or resist (successfully or not). If I could pose a question: If you drop a ball is the universe smaller than it would have been if you had not dropped it?

We have nothing with which to propel it faster. If light went faster, say 1.1 c, then that would be the barrier we could only approach and that would be the point where inertia would approach infinite.

"Worked best" is not the issue. I'm not advocating it, I just claim it can be done.

Only to help pose the question. If you assume enough matter to slow it down the question is the same. What role does space play in the momentum of the expansion. I am assuming that the expansion has momentum.

I assure you it doesn't! Try blowing through a straw if you want a simple example of the speed exceeding any "impacts". (and it's all impacts, though you can argue the molecule speeds are higher it is the same thing, the fluid can be accelerated, it must if it is funneled)

I think this is correct. So based on that rate, what inertia is the space assumed to have that must be "subdued" in order to arrest the expansion? As I think (?) you were pointing out the galaxies themselves are more or less at rest wrt the expansion, at least locally.

How is the momentum of the expansion thought to be measured? Assuming there is enough matter present to create a "big crunch" is it assumed that space will "shrink" (or slow in expanding, stall, then shrink) to the same beat as would be consistent locally with a gravitational collapse "in" space?

You need wind to sustain it, but it will go upwind. It's not a PMM.

Same amount at a faster speed. Net momentum transfer backwards of the air. It actually mixes with other air so another way of looking at it is that it is not the "only" air displaced backwards.

My point is that it is possible to do this. Direct more momentum backwards in spite of the fan facing forward.

As long as the sail/fan system can direct more air momentum backward than forward it can propel the boat forward. Also a fan can be set up to catch the wind and turn a water propellor which propels the boat straight upwind. No energy source other than the wind required.