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Cyclic Universe
Posted: Sat Jul 12, 2008 11:01 am
by harry
G'day from the land of ozzzzzzzz
Could the Big Bang be a recycled Big Bang or events of Big Bangs?
http://lanl.arxiv.org/abs/0801.2965
Cosmology and Cosmogony in a Cyclic Universe
Authors: Jayant V. Narlikar, Geoffrey Burbidge, R.G. Vishwakarma
(Submitted on 18 Jan 2008)
Abstract: In this paper we discuss the properties of the quasi-steady state cosmological model (QSSC) developed in 1993 in its role as a cyclic model of the universe driven by a negative energy scalar field. We discuss the origin of such a scalar field in the primary creation process first described by F. Hoyle and J. V. Narlikar forty years ago. It is shown that the creation processes which takes place in the nuclei of galaxies are closely linked to the high energy and explosive phenomena, which are commonly observed in galaxies at all redshifts.
The cyclic nature of the universe provides a natural link between the places of origin of the microwave background radiation (arising in hydrogen burning in stars), and the origin of the lightest nuclei (H, D, He$^3$ and He$^4$). It also allows us to relate the large scale cyclic properties of the universe to events taking place in the nuclei of galaxies. Observational evidence shows that ejection of matter and energy from these centers in the form of compact objects, gas and relativistic particles is responsible for the population of quasi-stellar objects (QSOs) and gamma-ray burst sources in the universe.In the later parts of the paper we briefly discuss the major unsolved problems of this integrated cosmological and cosmogonical scheme. These are the understanding of the origin of the intrinsic redshifts, and the periodicities in the redshift distribution of the QSOs.
Posted: Wed Jul 16, 2008 5:20 pm
by Arramon
Never really read up on this theory... interesting indeed.
http://www.fas.org/irp/imint/docs/rst/S ... iverse.jpg
The new cyclic universe theory says that there is no beginning or end of time.
http://physicsworld.com/cws/article/news/5383
Most cosmologists believe that the universe began with the big bang about 14 billion years ago, and has been expanding ever since. Many astronomical studies – including observations of receding galaxies and the cosmic microwave background – support this view. But this ‘standard theory’ has a glaring shortcoming: it cannot explain the big bang itself, or the conditions that created it.
Theories of ‘bouncing’ or cyclic universes, however, do not predict a beginning or an end of time, and therefore do not need to explain them. Early advocates of a cyclic model thought that the universe must shrink into a singularity – a point of infinite density and temperature – before exploding in a new big bang. But this idea proved too difficult to explain, and most theorists rejected the concept of a cyclic universe.
Now Steinhardt and Turok say that – according to ‘M-theory’ – the universe need not pass through a singularity between a big crunch and a big bang. Supported by most cosmologists, M-theory says that space–time has eleven dimensions, of which we perceive four: three in space and one in time. Our four-dimensional ‘brane’ – short for membrane – is moving among the remaining dimensions or branes, which are hidden at very small or very large length scales.
The theory says that the matter we see in the universe is confined to our local brane and that matter also exists in other branes. Steinhardt and Turok believe that a big crunch/big bang occurs when two such branes collide. They say that the density of matter is perfectly finite during such a collision, and that a singularity only occurs in the sense that the dimension that separated these branes disappears briefly during the collision.
The effect of gravity on matter in different branes could explain why galaxies behave as though they contain more matter than we can detect – a phenomenon that led to the concept of ‘dark matter’.
The researchers also say that their theory depends upon ‘dark energy’, another concept that is not explained by the standard model. Dark energy is a kind of repulsive gravitation, which was proposed to explain recent observations that show the universe is expanding at an accelerating rate. In the new cyclic model, dark energy is needed to dilute entropy during periods of cosmic expansion.
“If our conjecture is correct, it transforms cosmology because the big bang isn’t the impenetrable barrier it once seemed,” Turok told PhysicsWeb. He admits that the theory needs more work to solve several important technical problems, but says “philosophically, the model is so appealing that I think it will be here to stay for some time.”
http://www.sciencemag.org/content/vol29 ... /cover.dtl
Posted: Wed Jul 16, 2008 5:38 pm
by Arramon
Only thing for me, after thinking about this: what happens to the previous material created by one of the Bangs? If everything expands outwards and fades into non-existence or radiation as it states, does this Era of Darkness, before the next Bang occurs, constitute our universe (or 'brane' we are in) as being null of all light/matter/material and only empty space remains? And THEN the 'branes' collide and a Bang occurs..?
I would like to see some details about what the 11-dimensional membranes may look like. What about the M-Theory tieing it all together?
Posted: Thu Jul 17, 2008 10:21 am
by harry
G'day arramon
A cyclic universe is like a wheel, If we take the evolution of galaxies and observe their workings. We see so called stellar black holes growing larger as they approach the centre of the galaxy and in time matter via an active black hole are ejected back into space reforming the galaxy.
The following versions are ideas, i do not agree with them, but that does not mean they are wrong. Its just me. I posted them as information, as a point of view.
http://lanl.arxiv.org/abs/hep-th/0111098
Cosmic Evolution in a Cyclic Universe
Authors: Paul J. Steinhardt, Neil Turok
(Submitted on 12 Nov 2001 (v1), last revised 20 Mar 2002 (this version, v2))
Abstract: Based on concepts drawn from the ekpyrotic scenario and M-theory, we elaborate our recent proposal of a cyclic model of the Universe. In this model, the Universe undergoes an endless sequence of cosmic epochs which begin with the Universe expanding from a `big bang' and end with the Universe contracting to a `big crunch.'
Matching from `big crunch' to `big bang' is performed according to the prescription recently proposed with Khoury, Ovrut and Seiberg. The expansion part of the cycle includes a period of radiation and matter domination followed by an extended period of cosmic acceleration at low energies. The cosmic acceleration is crucial in establishing the flat and vacuous initial conditions required for ekpyrosis and for removing the entropy, black holes, and other debris produced in the preceding cycle. By restoring the Universe to the same vacuum state before each big crunch, the acceleration insures that the cycle can repeat and that the cyclic solution is an attractor.
This is one version of a cyclic universe. It will take many more years to understand the processes.
http://lanl.arxiv.org/abs/physics/0105064
The cyclic universe
Authors: Ding-Yu Chung
(Submitted on 21 May 2001)
Abstract: The cyclic universe model is a modification of the ekpyrotic universe and the pyrotechnic universe models. The cyclic universe goes through the six transitions: the triplet universe, the inflation, the big bang, the quintessence, the big crush, and the deflation transitions. The universe starts with eleven dimensional space-time with two boundary 9-branes separated by a finite gap spanning an intervening bulk volume. The triplet transition starts when the bulk 9-brane is generated from the hidden boundary 9-brane, and collides with the pre-observable 9-brane. The collision starts the inflation transition. The collision is the brane dimensional interference mixing between the pre-observable 9-brane and the bulk 9-brane. The results are the mixed branes (combined brane dimensions), the internal space (cancelled brane dimensions), the bulk space, 3-brane vacuum, and cosmic radiation. Cosmic radiation generated during the inflation leads to the big bang. Meanwhile, the hidden brane undergoes stepwise fractionalization, changing in stepwise manner from 9-brane to 3-brane. The observable universe expands in a constant rate until the quintessence transition. Afterward, there are the big crush transition (the reverse of the big bang) and the deflation (the reverse of the inflation). The cosmic cycle of the fractionalization and condensation starts over again. The masses of all elementary particles and hadrons can be calculated.
Posted: Thu Jul 17, 2008 4:38 pm
by Orca
“philosophically, the model is so appealing that I think it will be here to stay for some time.”
Things that make you go "hmmm..."
My question: can information pass from one cycle to the next?
If matter and energy are completely "reborn" between each cycle, all information from the last cycle would be destroyed by the creation of the new; thus, from our perspective, time ended and began again since our existence is completely contained within a single cycle.
If information can survive from one cycle to the next, who knows, I suppose you could say that time doesn't stop and start from our perspective and continues in a line. But that leaves haunting questions such as, "when was the yoyo
first dropped?"
Arramon, your image looks to me like the view from "10 Forward" while the Enterprise is at "warp speed."
8)
Posted: Thu Jul 17, 2008 6:05 pm
by Conro
discover recently did an issue on these theories. it was on the cyclic universe, the unverse as an arrow of time, and the universe as seperate Nows that make up everything, negating time. It was a very interesting article.
http://discovermagazine.com/2008/apr/25 ... big%20bang
The cyclic universe is basically as far is I can understand it, that there is one immense body of stuff, and as the stuff spreads out it creates emptiness where more universes(as we call them) are created in space, that eventually spread out so the majority is space again, creating more space.
Tell me if I'm wrong, I might have gone wide of the mark. Interesting theory, and ifit was right, would we be able to then observe the creation of another universe(when it happened of course)
Posted: Fri Jul 18, 2008 2:56 am
by harry
G'day from the land of ozzzzzz
The minute someone talks about recycling, people bring in time and space and so called wormholes that you can go from one universe to the next, oh! and many other dimensions.
The cyclic process occurs around us, within stars, compacted matter that some call black holes or Neutron stars or exotic stars etc.
The cyclic process that occurs in compacted matter(eg BH); matter is broken down to degenerate matter compacted than in time ejected via jets and reform galaxies. A simple process that has a never ending process and recombinations.
There are varies types of cyclic universes that involve the Big Bang theory and many alternative theories. Whats right or wrong? Who knows?
Posted: Fri Jul 18, 2008 4:11 am
by Doum
I dunno what is perfectly right. But i know that we human are getting closer to it. And i still think it isnt a recycliing univers. So i do still think that you are wrong Harry.
Keep smiling!
![Wink :wink:](./images/smilies/icon_wink.gif)
Posted: Fri Jul 18, 2008 4:38 am
by Orca
Harry, my point is that if information is destroyed with each cycle, there's no observable difference between a cyclic universe and the big bang. In other words, if there have been x cycles since this gravy train started, from our perspective we might as well conclude there's only been one since we can't ever observe evidence of any other.
It's like saying "yeah, but what's outside the universe?" This statement is meaningless because we have no way of making comparisons and thus no method for measurement.
You might say it's like trying to remember something that happened before you were born. The universe is self-contained existence.
Posted: Fri Jul 18, 2008 11:39 am
by harry
G'day from the land of ozzzzz
Orca said
Harry, my point is that if information is destroyed with each cycle, there's no observable difference between a cyclic universe and the big bang. In other words, if there have been x cycles since this gravy train started, from our perspective we might as well conclude there's only been one since we can't ever observe evidence of any other.
It's like saying "yeah, but what's outside the universe?" This statement is meaningless because we have no way of making comparisons and thus no method for measurement.
You maybe right, but for observations of phases (stages) of starformation and evolution of galaxies and theor varies forms that are dependent on the size and activity of the central compact body that some call black hole.
We can trace the cyclic process of stars and maybe get a critical date before they change phase.
This is interesting link
http://www.cosmology.info/newsletter/2008.04.htm
Are old galaxies smaller, bigger or neither?
Three new papers on galaxy size deepen the contradiction between expanding-universe predictions and measurements. Van Dokkum et al look at very massive galaxies at a redshift of about 2.3 and find that on average they are 5- 6 times smaller in radius and hundreds of times denser than massive galaxies in today’s universe. The densest of these high-z galaxies have densities five times that of any galaxies that now exist. The authors speculate that perhaps mergers may result in less dense galaxies, but mergers would also result in more massive galaxies, and some of the high-z galaxies are as massive already as the most massive galaxies observed today. So, if they merged, they would create galaxies larger than any we see. Since massive galaxies are easy to find, getting rid of either extremely massive or extremely dense galaxies is difficult, akin to hiding an elephant under a rug.
Sirocco et al confirm these results, reporting that at z=1.5 the surface brightness of galaxies, as determined with the conventional cosmology assumptions, is 2.5 magnitudes brighter than for nearby galaxies, which implies that, for a given luminosity, the galaxies have radii that are 3.2 times smaller.
On the surface, these results, taken in the context of conventional cosmology imply that smaller galaxies form first and then merge into larger ones. But more and more observations are showing that the oldest galaxies are the largest ones. Rakos et al find that in cluster galaxies that the most massive galaxies are the oldest ones, exactly the opposite of what would be expected if they are formed by merger of smaller galaxies. In addition, they find that galaxies in more massive clusters are also older, implying the clusters formed before the galaxies, again contradicting the conventional ideas of mass accumulating “bottom-up”.
To add to the puzzles presented by these papers, the average ages of the stellar populations measured by Rakos extend all the way up to the standard “age of the universe” of almost 14 Gy. This is a problem, since even in elliptical galaxies, there is some star formation going on. Since some stars in these populations are a lot younger than 14 Gy, there must be some older than 14Gy for the average to be that age. This creates the conundrum of having stars older than the universe.
These puzzle all find easy resolution if the universe is not in fact expanding. In a non-expanding universe, a galaxies physical size is proportional to its angular size times the redshift. If this formula is used for the samples studies by van Dokkum and Sirroco, rather than the formula based on the expanding universe, the galaxy sizes are almost exactly the same at high redshift as at the present time. As well, if the universe is not expanding, and there was no Big Bang, stars can be older than 14 Gy.
Before you close you mind on the cyclic process, read about it.
What we are actually seeing is how the parts within the universe go on with their daily life.