Question Cyclical Universe

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Mar 19, 2020
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Tell me a subject about which Cat doesn't know.
I recall him having a minor difficulty with the stereochemistry of amino acids, ribose and deoxyribose, and nucleotides required in the three dimensional structure of complex biomolecular assemblies and interactions. It was likely my fault for not providing sufficient details..............
 
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Well, no natural law does explain a cyclical universe. Or, does every natural law does?
Okay, according to my knowledge of universe (that's really less compared to you all), until now, there's no evidence that dark energy is not constant. As far as I know, dark energy is constant. And that means, the universe is gonna expand forever. Er, and that's why we can say that a universe cycle theory is falsified by this.

But there, logic says that a universe cycle theory is not impossible. I mean, the big bang happened. So, there might be a universe before this and before this and before this. So, well, the cycle goes on.

But there again, the first law of thermodynamics says that energy cannot be created or destroyed, but it can transformed from one form to another. Well, there wasn't any energy at 0. (Please, no void potential energy, it isn't logical) So, the logic for a cyclic universe gets out of circle.
What is more logical, the reason for everything is a quirk of nature that 0= some tiny energy.?

0=tiny potential energy and no more and no infinite mass/energy and no more creation of new energy or destruction of existing energy.
Quantum fluctuation balance E set by that tiny potential energy of 0.
All self regulated.

Or dark energy can expand it's potential energy eventually becoming infinite?

If dark energy/mass really do exist as permanent items and not just a temp byproduct of fluctuation then eventually the infinite comes into play and consumes the universe into one big black hole forever.
 
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Apr 5, 2020
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What is more logical, the reason for everything is a quirk of nature that 0= some tiny energy.?

0=tiny potential energy and no more and no infinite mass/energy and no more creation of new energy or destruction of existing energy.
Quantum fluctuation balance E set by that tiny potential energy of 0.
All self regulated.

Or dark energy can expand it's potential energy eventually becoming infinite?

If dark energy/mass really do exist as permanent items and not just a temp byproduct of fluctuation then eventually the infinite comes into play and consumes the universe into one big black hole forever.
Well, dark energy and dark matter are separate things. And among the two, we know more about the latter. And also, I don't think 0= tiny speck of energy. It seems illogical to me.
 
Well, dark energy and dark matter are separate things. And among the two, we know more about the latter. And also, I don't think 0= tiny speck of energy. It seems illogical to me.
They could simply be 2 formats of the same thing, or not exist as permanent items at all.

Yep it's madness to think of this universe coming into existence just because nothing has potential energy.
It does answer why black holes don't shrink forever, how this universe started, how big bangs happen and why energy is stable and set and can't be destroyed.

They have created tiny places of nothing in science and physics gets real weird in them while they exist for a fleeting instant.
 
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rod

Oct 22, 2019
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FYI. Going back to post #26, there is no natural law explanation for a cyclical universe. The NASA ADS Abstract service has a number of papers available on cyclical universes. The studies use *new physics* like quantum gravity, inflatons, etc., not well documented natural law like Kepler's laws, law of gravity, or laws of motion. Verifying the new physics is ongoing but not *settled science*. Another problem is the hand waving I see over the 1st law and energy conservation in some posts. It seems this law is used to argue that the universe can be cyclical. However, the 2nd law, increasing entropy is clearly winning out in the universe we see today. Here are some examples from astronomy.

“Astronomers studying galaxy evolution have long struggled to understand what causes star formation to shut down in massive galaxies. Although many theories have been proposed to explain this process, known as "quenching," there is still no consensus on a satisfactory model.", ref - https://phys.org/news/2020-07-galaxies-die-insights-quenching-star.html

Another new report, https://phys.org/news/2020-07-astronomers-x-ray-luminous-high-redshift-quasar.html
From the arxiv paper, "All these observational facts clearly draw a picture of violent star formation and rapid SMBH growth taking place hand in hand in CFHQS J142952+544717.” My notes, The redshift distance is 12.814E+9 LY light-travel-time or 3.93E+9 pc. SMBH 2E+9 solar masses, diameter = 78.964 AU. Distance 3.93E+9 pc, angular resolution size = 2.0093E-5 mas. An important observational comment in the arxiv report, "All these observational facts clearly draw a picture of violent star formation and rapid SMBH growth taking place…" Also, "All observed quasar spectra have redshifts between 0.056 and 7.54…"

Astronomy does not observe new quasars forming, new galaxies forming, new globular clusters forming, new SMBH forming or even, new PBH forming :). What is documented shows the *origin processes* changed greatly, and slowed down dramatically since the early universe. This points to an expanding universe that is running down hill, not up hill and entropy working more and more disorder and eventual heat death. Folks can believe in a cyclical universe to avoid perhaps unpleasant philosophical implications of a universe with a distinct beginning and universe that is winding down. However, it is not *settled science* and lacks rigorous observational testing presently to confirm such a view of the universe.
 
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Astronomy does not observe new quasars forming, new galaxies forming, new globular clusters forming, new SMBH forming or even, new PBH forming :).
Right, but don't confuse the Cyclical Universe idea with the old Static Universe where new things keep forming in an ageless universe. A cyclical universe would need to eventually collapse, which allows the next one to form, though I assume there is no hard science for this since falsifiability is a requirement for a scientific model.

This points to an expanding universe that is running down hill, not up hill and entropy working more and more disorder and eventual heat death.
Yep, stars poop out, and there is less and less hydrogen for new ones. The universe is aging, and the entropy increase describes the "take down", no doubt.

If it holds that the universe is accelerating in expansion -- the evidence is fairly strong already -- it will put a big kink in any cyclical "model", which requires a hot death (complete contraction) not a cold one.

However, it is not *settled science* and lacks rigorous observational testing presently to confirm such a view of the universe.
I suspect it has no real objective testing.
 
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Mar 19, 2020
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..... I assume there is no hard science for this since falsifiability is a requirement for a scientific model.
"Falsifiability" as a requirement for a scientific model requires in itself to be a properly designed experiment, and the results of which must be correctly interpreted. (e.g. abiogenesis - science or faith, and homogenized frogs).

Experimental design and correct interpretation of results are the most fundamental aspects of real scientific investigations, and are therefore the foundation of all modern sciences.
 
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"Falsifiability" as a requirement for a scientific model requires in itself to be a properly designed experiment, and the results of which must be correctly interpreted. (e.g. abiogenesis - science or faith, and homogenized frogs).
Right. The big difference between faith and science is whether or not those interpretations are objective, where essentially multiple testings of any given hypothesis can be conducted by multiple experts to add confidence to any given interpretation another has given for the claim. The claims can also be "in principle", which is why Einstein enjoyed using "gedanken experiments" (thought experiments).

If a cyclical model exists that meets the above, I'd like to see what reasonable tests are offered by it.

Experimental design and correct interpretation of results are the most fundamental aspects of real scientific investigations, and are therefore the foundation of all modern sciences.
Yes, and what constitutes "correct interpretations" are the ones that are objective-based, not merely those based on subjective reasoning. Of course, great science often comes from great ideas that are simply subjective to begin with, but the ideas may or may not produce the falsifiability every theory needs.
 
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Right. The big difference between faith and science is whether or not those interpretations are objective, where essentially multiple testings of any given hypothesis can be conducted by multiple experts to add confidence to any given interpretation another has given for the claim. The claims can also be "in principle", which is why Einstein enjoyed using "gedanken experiments" (thought experiments).

If a cyclical model exists that meets the above, I'd like to see what reasonable tests are offered by it.

Yes, and what constitutes "correct interpretations" are the ones that are objective-based, not merely those based on subjective reasoning. Of course, great science often comes from great ideas that are simply subjective to begin with, but the ideas may or may not produce the falsifiability every theory needs.
Quite correct, Helio. This simple exchange on fundamental scientific principles is the basis for the "general consensus" by which real science establishes confidence in its observations and conclusions.
 
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I'm still curious if there is any objective evidence that would allow any reasonable interpretation for a Cyclical Universe model. Brian Greene does a nice job in providing some mathematical analysis that does suggest a 10^500 number of universes, but math alone doesn't meet the test for a scientific theory. [I think there is also a 10^1000 math version as well, IIRC, which isn't that large a number when it comes to probabilities.]
 
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Again, very sorry if this is redundant in the least from past posts, but a neurological download has begun and must proceed:

Just for a WAG, a recycling universe should have a starting point in the literal, but not figurative sense. This is because we see so many major changes over billions of years in the observable universe, and no one is seriously suggesting that what we have seen so far is reversible. Clearly we are well past a BB, and see an evolving universe, so there seems to be a set course that any cycle must follow. At least the current cycle we are in has a set course which we can observe, up until "now".

As a result, it would seem that a cyclic universe would have to be biphasic (at minimum), with an intermediary point of "zero-space-time" as the "beginning" of each new cycle. Each new cycle seemingly must start with the "end" of the degenerate matter-energy-space-time of the last cycle. This does not imply a big crunch, a true beginning or end, but some mechanism which resets all aspects of the universe in order to recycle, and particularly resetting space-time to zero.

Since the BB is, for us, a large scale dissociative process, it is reasonable to suggest that this is the beginning of a new cycle, and, for us, it is very early in the game. Since many or all things we see seem dissociative, and due to entropy, and the proposal that the universe is fated to a heat death, there must exist some mechanism which evades this fate to begin another cycle.

It seems reasonable that there is only one force that would be the fundamental driver of universal recycling, and that is gravity. Even if everything is converted into ER, it all has mass-equivalence. Which means it should be able to reassemble, assuming the "universal field strength" is sufficient to initiate a reboot.

Gravity is an associative force, and would appear to be the primary suspect in sustaining a cycling universe. There seems no other force with the required properties to put it all together again, so to say.
 
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I'm still curious if there is any objective evidence that would allow any reasonable interpretation for a Cyclical Universe model. Brian Greene does a nice job in providing some mathematical analysis that does suggest a 10^500 number of universes, but math alone doesn't meet the test for a scientific theory. [I think there is also a 10^1000 math version as well, IIRC, which isn't that large a number when it comes to probabilities.]
Here is an interesting thought and simple reason the universe collapses.
Dark energy is correct and expansion continues at an ever increasing pace.
Everything in the universe reaches C and explodes from matter to radiation.
Since everything is at C the conversion of matter to radiation can only happen to slow the expansion by 90 95% since it can only happen in the direction slower than C or inwards.
Expansion stopped,self gravitation collapse.
When everything is back to 1 universe size black hole gravity overwhelms time and is unstable.

A solution for sure for 1 single universe that is cyclic.
Me i think the universe is far grander than just 1 universe and lots of reasons why infinite universe can make cyclic universes.

"Falsifiability" as a requirement for a scientific model requires in itself to be a properly designed experiment, and the results of which must be correctly interpreted. (e.g. abiogenesis - science or faith, and homogenized frogs).

Experimental design and correct interpretation of results are the most fundamental aspects of real scientific investigations, and are therefore the foundation of all modern sciences.
If the understanding of the reality is not correct then how to measure it against reality?
Faulty math from a bad conception will be the rule.
Ask Einstein about that one, and the person that has new math to correct it can we trust that?
 
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rod

Oct 22, 2019
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FYI. In post #35, Helio said "I suspect it has no real objective testing." In all of the posts presented in the discussion here, I do not see one or more tests that confirm a cyclical universe view documented. Claims that suggest our understanding of reality cannot produce a valid test (it seems this is the logic), example post #42, look more like hand waving. Here is another report showing the universe with large redshifts, is very different than what we live in today. 'Hundreds of candidate galaxies identified in the protocluster D1UD01', https://phys.org/news/2020-07-hundreds-candidate-galaxies-protocluster-d1ud01.html

My observation. More evidence using large redshift values showing the universe is following the path of entropy, i.e. the 2nd Law. Star formation and galaxy cluster formation, slowing down and ending as a process in BB cosmology model. This clearly points to a universe with a definite beginning, and expanding based upon the cosmological redshift interpretation, following the 2nd Law. The arrow of time is moving down, not up.

In BB cosmology, the redshift or z number for the CMBR, z ~ 1100. In astronomy, large redshift objects are documented to z ~ 12.0. In the cyclical universe view, what is the value of z for objects when the universe starts to contradict and move towards another cycle? Example, z = 1200?, z = 10000?

Interesting observational test for the cyclical universe view :) I suggest that there is *no real objective testing* supporting the cyclical universe view and none has been presented in this thread.

Okay, *contradict* is shrink :)
 
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Jun 1, 2020
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Here is an interesting thought and simple reason the universe collapses.
Dark energy is correct and expansion continues at an ever increasing pace.
Everything in the universe reaches C and explodes from matter to radiation.
But there are regions (closer ones) we can observe that are already moving away from us > C.

Since everything is at C the conversion of matter to radiation can only happen to slow the expansion by 90 95% since it can only happen in the direction slower than C or inwards.
GR demonstrates that any one point can be treated as not moving. So from many outer regions were moving faster than C.

Expansion stopped, self gravitation collapse.
It's held that Dark Energy is gaining the upper hand over gravity as the density of the universe decreases with time. So, it will continue to accelerate and not stop.

In BB cosmology, the redshift or z number for the CMBR, z ~ 1100. In astronomy, large redshift objects are documented to z ~ 12.0. In the cyclical universe view, what is the value of z for objects when the universe starts to contradict and move towards another cycle? Example, z = 1200?, z = 10000?
DE must be turned off first. We don't know enough about DE to have a clue if it will change in behavior in the future. The CMBR z value was once 0, ~ 1100 now, and with accelerated expansion it will continue to increase at a faster rate than before.

Interesting observational test for the cyclical universe view :) I suggest that there is *no real objective testing* supporting the cyclical universe view and none has been presented in this thread.
That's a safe bet.
 
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Apr 5, 2020
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Well, I have a question. If the first universe in the cycle (I am assuming that this one isn't the first one) had the same properties as of now, how did it even go back to a blackhole size? How did expansion stop? I mean, the first universe should also have a constant dark energy, and constant dark energy= expansion never stops, if it has the properties of the present day universe. How did expansion stop in Universe 1?
 
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Well, I have a question. If the first universe in the cycle (I am assuming that this one isn't the first one) had the same properties as of now, how did it even go back to a blackhole size? How did expansion stop? I mean, the first universe should also have a constant dark energy, and constant dark energy= expansion never stops, if it has the properties of the present day universe. How did expansion stop in Universe 1?
Hi IG

Gravity
 
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Cat beat me to the punch. That is correct. Gravity seems to be the over-riding force in the universe.

It exists both in matter and ER, since energy has mass-equivalence.

A cherry red-hot steel bar weighs more than it does at room temperature !

So a universal mass-equivalence factor must be required for an apparently expanding universe to recycle. There seems no other force that could reverse the observed cosmic momentum.
 
Jun 1, 2020
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Well, I have a question. If the first universe in the cycle (I am assuming that this one isn't the first one) had the same properties as of now, how did it even go back to a blackhole size? How did expansion stop? I mean, the first universe should also have a constant dark energy, and constant dark energy= expansion never stops, if it has the properties of the present day universe. How did expansion stop in Universe 1?
Good questions. If DE were to reverse somehow, or lose its repulsive nature then the gravity might be enough to cause a full collapse? But would space itself fall with it? Who knows. DE is a major mystery. Einstein had snuck it into his equations (Cosmological Constant) once he saw that gravity would collapse our universe without it, but his value was much, much smaller than what we need today for an accelerating universe.

Even Lemitre respected this issue and had the universe accelerating for a period.

I would find it surprising given the acceleration discovery if many favor the cyclical model; it's hard to get something to collapse when it is expanding faster and faster all the time.
 
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I would find it surprising given the acceleration discovery if many favor the cyclical model; it's hard to get something to collapse when it is expanding faster and faster all the time.
Certainly agree with Helio on this. Playing around with a recycling universe was just for fun. What really happens is anybody's guess.

That long, slow ever-expanding heat death is too ugly to inspire, and harder still to accept.

But, as they say, entropy rules!
 
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Hi IG

Gravity
Cat beat me to the punch. That is correct. Gravity seems to be the over-riding force in the universe.

It exists both in matter and ER, since energy has mass-equivalence.

A cherry red-hot steel bar weighs more than it does at room temperature !

So a universal mass-equivalence factor must be required for an apparently expanding universe to recycle. There seems no other force that could reverse the observed cosmic momentum.
My first point, to both Cat and dfjchem, is that, if gravity is really so powerful, then this heat death theory is completely nullified. According to the heat death theory, after a googol years, or 10 to the power 100 years, the whole world will calm down, literally calm down. Well, that means that Blackholes will stop to radiate energy. Of course not! If gravity is really that powerful, blackholes will exist even after a googol years. And, if blackholes exist, then it will be foolish to think that Hawking Radiation will stop.

Gravity is not that powerful. If it were, we would have been in a big blackhole right now.
Good questions. If DE were to reverse somehow, or lose its repulsive nature then the gravity might be enough to cause a full collapse? But would space itself fall with it? Who knows. DE is a major mystery. Einstein had snuck it into his equations (Cosmological Constant) once he saw that gravity would collapse our universe without it, but his value was much, much smaller than what we need today for an accelerating universe.

Even Lemitre respected this issue and had the universe accelerating for a period.

I would find it surprising given the acceleration discovery if many favor the cyclical model; it's hard to get something to collapse when it is expanding faster and faster all the time.
Well, that's the point, we don't know. We don't know yet. But, as far as astronomers observations go, dark energy remains constant. And, if it really remains that constant, a heat death is inevitable. One day, all the quarks in the universe will be so far from each other that even gravity won't be able to make them join together again. And with that, the cyclic universe theory is falsified. And, @rod , there you go, even the cyclic universe theory can be nullified. Now, you can't say that it can't be a theory. Sad that all our endeavours will have no value after a googol years. Really sad....
 

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