J.C.MacSwell

The laws don't change. The application of the laws changes.

Welcome home!

We are currently top dog. What current species lineage is most likely to succeed us here on Earth? Obviously the endangered ones are unlikely, but none are 100.00...% out of contention until they are extinct (and all their DNA squashed) Chimps? Gorilla? ...I don't think they will outlast us even if it is our fault not theirs, but maybe they could sneak past a virus that wipes out the rest of us. A lot depends on how we do ourselves in, winning the Darwin award for our species as a whole and leaving who knows what type of vacuum at the top. Rat? Cockroach? ..one or both should survive our Nuclear annihilation Oak? Maple?...woodent think so but there are no wrong answers. Dolphin? Porpoise? I don't sea it. Muskrat? Beaver? Dammed good choice if you can make a good case for them. Though it's likely some strain of bacteria I don't even know about my vote goes to the raccoon; Cunning little buggers with opposable thumbs (worked for us). We've crowded them out, and yet they're doing better than ever, but the main reason is that I've always liked them so they get my vote. Who, and for what reason, gets your vote for most likely to succeed?

Glass certainly can fatigue, and short term exposure can break glass, so the answer would have to be yes, it can. It can also flow under long term loads without breaking so the fatigue may to some degree be reversible.

No confusion. That is what I meant to ask - So collapsing (as well as expanding) is consistent with GR, but not with observation.

The force vector must be placed in such a way as to slow the ring down without slipping. Nature does this automatically, as She reduces the momentum and angular momentum of the ring. This will not be the same for the disc, as the momentum and angular momentum are proportionally different. But neither of these cases match the diagram of the Wiki link. At constant velocity, where the disc and ring have a driving force to match the rolling resistance, there is no difference, the rolling resistance force vectors can be the same in each case, assuming the driving force is applied the same in each case. This is not the case you are describing as you do not have constant velocity. An analogy would be the force of friction between the rock and the ground, if you are pushing on it, or a small squirrel is pushing on it- if it doesn't move, then it doesn't move, but the force is not the same. Until it budges, the rock "knows" how much and in what direction to push back. And in all the cases you describe, the track "knows" how much to push back as well. Nature does the accounting, and leaves no "paradox".

If you give a link showing a diagram I will be happy to comment on it. This link: http://en.wikipedia.org/wiki/Rolling_resistance ...we already know does not represent your case.

How can a redshift indicate collapse?

...and yet, one loses proportionally more momentum than the other, and the other proportionally more angular momentum. ...and of course, you can't be wrong so... Paradox!

Didn't I already explain this to you next week?

All but the most local are red-shifted. That is evidence they are moving apart from us. From our rest frame it is them moving, from their rest frame it is us moving.

I guess my point was that if the parameter could be adjusted for an acceleration, could it not be adjusted for a deceleration, and since enough deceleration leads to contraction... then how can it be inconsistent with the theory? Having said that, bringing things back to another thread with respect to time frames, if the contraction started everywhere at "once", we would notice a blueshift locally far before waiting for the blueshift from the far reaches of the universe, correct?

If you draw it, you might see the difference and begin to understand. It is not the shape, it's the way the force vector must be applied in each case, to slow down the disc and ring without slipping. They have the same amount of momentum. They have different amounts of angular momentum. This affects the way any force vector must be applied to slow down the disc or ring without slipping. You might then see how it applies in the simplest case of a fixed straight track. If you cannot do this how can you possibly understand the more complicated isolated circuit track. Merged post follows: Consecutive posts merged Thanks BN. The curious thing is, that he offered to do just that, fix any errors or omissions if I pointed them out, but he seems to balk at doing it. From his link in the first post he is obviously capable of drawing, he just needs to slow down and do it. I would be happy if he at least gets this one part right for now, the deceleration of the disc and ring on a fixed straight track. I suspect he will not get it right the first time he tries it, since he thinks they are the same, but it will be a start.

So you can prove this by drawing it on a free body diagram. Draw me a force, that will slow them down as you describe.

70+ posts and no one has mentioned the Nazis, and no one has asked "what can a guy do, when a dog comes on to him". Not bad.

Yes. This is why we let our teenagers drive, instead of relying on sound signals and operating the controls from our house.

In the current model the expansion is accelerating, correct? Is that consistent with GR? Or did they have to add (and start searching for) a factor to make it work?

A force is a vector quantity. You have chosen to model the ring with the same mass as the disc but higher moment of inertia. They have different ratios of mass to moment of inertia. If they roll without slipping while decelerating the decelerating force cannot be applied the same way. Not in the real world and not in an idealized model. You can simplify and say they are approximately the same, but don't point to the difference later and say "Paradox". When forces don't balance or momentums don't balance in an isolated system that is a sign that you have made a mistake, not a sign that there is an exception to a physical law.

It depends on a lot of factors. I was hoping you would draw the force vectors and see the difference between the disc and ring and to see what it meant to have the "same" rolling resistance for decelerating discs or rings. The resultant force vectors cannot have the same magnitude, direction and application point in each case (unless at least one of them is skidding to some extent)

The drawing shows a wheel being pulled with constant velocity against rolling resistance. Deceleration due to rolling resistance will be different from that.

That's basically the idea. Blood alternately rushes to your head or feet but the background doesn't spin. After observing you go back to normal mode.

Draw it and see.

Start with a free body diagram. Draw the forces on ring or disc showing rolling resistance.

If it was shrinking it would be blue-shifted.

Does it come with a tether? Looks like it would make a good counterweight for Sisyphus's idea.