Cosmological concept change

No I'm not confused, but not interested in arguing either. Do carry on. Supporting both diametrically opposed sides.

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Well you certainly have it wrong then...: The gist of this thread was the OP saying that accelerated expansion was unlikely, followed by reasons as to why it still stands.
The Professor Carroll link was given in answer to post 30 and the "DE breaks the conservation of energy law"

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Uh huh.

 

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Let's be crystal about what Carroll said. He said that photons lose energy and redshift as SPACE EXPANDS.

Space does not expand. The distances between objects made of bound energy expand. It is not the same thing as space expanding, and if space expanded the way Carroll described, it would break the rule of Special Relativity that says that the speed of light is the same as measured by all observers.

Think of it this way. If space could "expand" on large scales, then it could also "expand" on smaller, or more local ones. We would see pockets of empty space where the speed of light to traverse that space would be different than it was in a place where space was not expanding. Or else you would need to explain why this works on large scales and not smaller ones. Why don't you know "bunk" when you see it? Why doesn't anyone? The law of gravity works EVERYWHERE. Space "time" is isotropic EVERYWHERE, even if time dilation due to a local concentration of mass/energy is not. The CMBR is pretty much isotropic EVERYWHERE. A law is a law. Bunk is bunk, and it's not extensible. If a law doesn't apply EVERYWHERE, they you are saying the law is bunk, or in other words, NOT a law of physics. And this is exactly why I don't even bother to read stuff on Carroll's "Preposterous Universe" any more. Too preposterous for my taste.

Got it?

 

It does break that rule, because it is a feature of GR, which breaks all sorts of SR rules.

You are like someone complaining that American football breaks the rules of rugby or that baseball breaks the rules of cricket.

AND IT DOES!

AND WE DO!

No, spacetime is not isotropic everywhere, which is why this it is applied as a correction factor in some cosmological investigations. Hence the discussion of "swiss-cheese" models in the Nobel prize winning supernova papers.

Yeah, "pretty much". It is in the measuring of just how "pretty much" that one gets a measurement of mass-energy distribution. WMAP measures the anisotropy of the CMBR, i.e., not-isotropy.

 

I suggest you read the whole article again and your interpretation of what he said, which btw he also mentioned.

Smaller local regions of spacetime, that have a larger mass/energy density, simply overcome the overall large scale expansion rate: eg. Imagine a fish swimming upstream at 5kms/hr, against a current of 10kms/hr.

Professor Carroll's explanation of what we observe is spot on. I suggest you review your opinion of what you see as bunk.

You seem as "taken" with Professor Carroll's explanation, as you were with Professor Thorne's.

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Here's some more answers for you to contemplate.......
http://physics.stackexchange.com/qu...nsistent-with-conservation-of-mass-and-energy
The total energy in the space does increase, precisely because of the reason you mention. Energy is not expected to be conserved, because the metric is not invariant under time translations.

What does hold is the first law of thermodynamics, dU=−PdV+⋯. Since the pressure in this system is negative, this is one way of seeing the origin of the extra energy as the space grows.
or.....
https://www.quora.com/Does-dark-energy-violate-the-law-of-conservation-of-energy-mass
The law of conservation of energy is not applicable to cosmology, because the principle only holds when the background is time-translation invariant, which is clearly not the case in a Big Bang universe. You can write down a form of energy conservation at a given point in the universe, since space is locally Minkowskian and therefore time-translation invariant, but you can't integrate it up.

Perhaps I need to ask, have you got it?
In essence the point being made is that what we call a law of physics, "the conservation of energy" is really only an approximation and does not hold where spacetime expansion and DE is concerned.