New evidence of a possible cyclic universe.

[shunyadragon]

New evidence of a possible cyclic universe.

Source: https://physicsworld.com/a/new-evidence-for-cyclic-universe-claimed-by-roger-penrose-and-colleagues/

New evidence for cyclic universe claimed by Roger Penrose and colleagues

© Copyright Original Source

[One Bad Pig]

Wouldn't signs left over from a previous cycle necessarily make the starting conditions NONsmooth?

[lee_merrill]

I wouldn't jump on the bandwagon just yet!



Blessings,
Lee

[shunyadragon]

I wouldn't jump on the bandwagon just yet!



Blessings,
Lee

The reason I added the proviso 'possible.' Yes it is at present controversial. Beyond the Planc time of the early expansion of our universe I am skeptical of all the hypothesis concerning the origins of our universe At present not enough information to definitively choose one over the others.

[shunyadragon]

Wouldn't signs left over from a previous cycle necessarily make the starting conditions NONsmooth?

Not enough information.

[Leonhard]

Wouldn't signs left over from a previous cycle necessarily make the starting conditions NONsmooth?

You'd be right. Penrose does have an answer for that. His idea is that black holes don't obey the laws of thermodynamics. This isn't as far out as it sounds, because if you just "do the math" then current physics gives that they don't. The expectation of most physicists is that black holes do obey the laws of thermodynamics ultimately.

So basically at the end of the universe we have a gas of particles that is mopped up by black holes. The black holes evaporate slowly over a period of years into a soup of gravitons and photons (with a very low entropy - as per his assumptions regarding black hole behaviour). And then lo and behold, this ends up looking pretty much exactly the same as the initial conditions.

He's been searching the Cosmic Microwave Background radiation for effects he should be able to predict from this. So far though he's turned up empty handed whenever further studies have been made.

Having heard interviews from him and read his books he personally seems to think this possibility as just that. A possibility worth exploring. And he's doing that. So far he doesn't have any credible evidence to make it anything more than an interesting hypothesis.

[Sparko]

Not enough information.

By definition, if the universe shrank to a singularity, there would be no place for these left over remnants to exist in to affect the next cycle. Even black holes have to exist at a location in space/time.

[shunyadragon]

By definition, if the universe shrank to a singularity, there would be no place for these left over remnants to exist in to affect the next cycle. Even black holes have to exist at a location in space/time.

Most cyclic universes are not necessarily based on the reduction of the universe to a singularity, though this seems to make that assumption, with no relics of a previous nor another universe. We do not have enough information to assume what is the nature of the singularity. All science is objectively able to do is replicate the nature of the expansion as some planc seconds after the hypothetical beginning of the expansion of the universe.

Beyond this, at present we have only the possibility of different hypothesis of origins, such as, the multiverse, cyclic universes, and black hole universes.

We have no definitive objective verifible evidence for any sort of 'absolute' beginning.

[Sparko]

Most cyclic universes are not necessarily based on the reduction of the universe to a singularity, though this seems to make that assumption, with no relics of a previous nor another universe. We do not have enough information to assume what is the nature of the singularity. All science is objectively able to do is replicate the nature of the expansion as some planc seconds after the hypothetical beginning of the expansion of the universe.

Beyond this, at present we have only the possibility of different hypothesis of origins, such as, the multiverse, cyclic universes, and black hole universes.

We have no definitive objective verifible evidence for any sort of 'absolute' beginning.

But you believe God created the universe, right?

[QuantaFille]

Beyond this, at present we have only the possibility of different hypothesis of origins, such as, the multiverse, cyclic universes, and black hole universes.

We have no definitive objective verifible evidence for any sort of 'absolute' beginning.

From what I understand, we have the wrong amount of energy and matter for there to have been an infinite number of cycles in a cyclical universe, only about a hundred or so. So you still have to explain what caused the cycles to start cycling in the first place.

[Sparko]

From what I understand, we have the wrong amount of energy and matter for there to have been an infinite number of cycles in a cyclical universe, only about a hundred or so. So you still have to explain what caused the cycles to start cycling in the first place.

actually I thought the wmap project proved that this universe cannot collapse. It will continue to expand until it fades away.

[QuantaFille]

actually I thought the wmap project proved that this universe cannot collapse. It will continue to expand until it fades away.

Yeah, but assuming something could cause matter to move in the opposite direction from that caused by the big bang (a pretty big assumption), you don't have enough matter and energy to keep doing it over and over, infinitely. And momentum means that once something is in motion, it takes a lot of energy to change its direction. If you wait for it to come to a stop, and then push or pull it back in the direction it came from, you need at least as much energy as that which put it in motion initially to get it back to its starting point.

[shunyadragon]

From what I understand, we have the wrong amount of energy and matter for there to have been an infinite number of cycles in a cyclical universe, only about a hundred or so. So you still have to explain what caused the cycles to start cycling in the first place.

From what you understand? I do not believe there is any science behind this assertion. IT would also assume that the cyclic universe is a closest system, and we have insufficient information for either assertion.

[shunyadragon]

actually I thought the wmap project proved that this universe cannot collapse. It will continue to expand until it fades away.

No. This hypothesis uses the same information, and proposes a different hypothesis.

[shunyadragon]

But you believe God created the universe, right?

My beliefs are not an issue here. This is a science topic in Natural Science 301.