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Origins of the Universe
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day from the land of ozzzzzzzz
The overall scope of cosmology involves observations and explanations of how stars and black holes work. Quantum mechanics explains the processes that trigger supernovas and explains how compact matter can exist and how jets can be formed.
Its not a competition of which theory to pick on. It's a team effort to explain the workings. Quantum mechanics cannot do it without observations and vis versa.
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CFB
 - Joined on 11-04-2007
- Sterling, VA
- Posts 116
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Re: Origins of the Universe
In your first reference
The big bang today relies on a growing number of hypothetical entities, things that we have never observed-- inflation, dark matter and dark energy are the most prominent examples. Without them, there would be a fatal contradiction between the observations made by astronomers and the predictions of the big bang theory.
There is evidence that dark mater has been observed http://en.wikipedia.org/wiki/Image:060821_darkmatter.jpg subsequent to the open letter. Inflation, of course, cannot be observed, but is inferred from COBE and WMAP measurements and dark energy is so new that fitting it into a standard model is a work in progress. This does not say that the BBT is correct, but it is the leading model that best fits observations. As observations become better, possibly another theory will replace it. This is not putting all eggs in a single basket, it is the process of science.
CFB
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CFB
- Joined on 11-04-2007
- Sterling, VA
- Posts 116
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Re: Origins of the Universe
"This is not evidence, we live in the modern era."
Harry, I believe that it is evidence of observing dark matter, but not proof.
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day CFB
Define Dark matter.
Unseen matter does not mean Dark Matter.
Just because you believe does not make it evidence.
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CFB
- Joined on 11-04-2007
- Sterling, VA
- Posts 116
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Re: Origins of the Universe
Dark matter is matter that only interacts with normal matter through gravity. Unseen matter may be unseen because our instruments are inadequate. Scientific evidence serves to either support or counter a scientific theory or hypothesis. The picture in question is scientific evidence that serves to support a hypothesis of dark matter. Gravitational lensing effects are another piece of evidence that tend to support a hypothesis of dark matter. Rotational curves of galaxies started the hypothesis that there was matter in galaxies that only interacted gravity.
I nether believe or disbelieve in the BBT, but I have not seen a hypothesis or theory the has a better fit to the scientific "observational" evidence. A better theory may be available, but so far I have not seen it. Remember a theory must explain observations, belief is not an issue.
CFB
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day CFB
The cyclic process expalins all observations without adding ad hoc ideas such as expansion of timespace, dark matter and dark energy and so on.
| http://lanl.arxiv.org/abs/hep-th/0205180 |
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| Bouncing and cyclic universes from brane models |
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| Authors: Sudipta Mukherji, Marco Peloso |
| (Submitted on 17 May 2002 (v1), last revised 25 Nov 2002 (this version, v4)) |
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Abstract: We consider a D3-brane as boundary of a five dimensional charged anti de Sitter black hole. We show that the charge of the black hole induces a regular cosmological evolution for the scale factor of the brane, with a smooth transition between a contracting and an eventual expanding phase. Simple analytical solutions can be obtained in the case of a vanishing effective cosmological constant on the brane. A nonvanishing cosmological constant, or the inclusion of radiation on the brane, does not spoil the regularity of these solutions at small radii, and observational constraints such as the ones from primordial nucleosynthesis can be easily met. Fluctuations of brane fields remain in the linear regime provided the minimal size of the scale factor is sufficiently large. We conclude with an analysis of the Cardy-Verlinde formula in this set up.
and
and if you read the papers from:
http://www.cosmology.info/newsletter/2008.10.htm
You may get a better idea.
Without further reading and a better understanding i would expect people to keep on thinking along the lines of the BBT.
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CFB
- Joined on 11-04-2007
- Sterling, VA
- Posts 116
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Re: Origins of the Universe
Harry, The Brane model is interesting, but does not seem to have any testable predictions. The weakness of this model, and almost all Brane models, is that an infinite number of possible solutions are available. A theory must have testable predictions to be a candidate.
The second paper is much better in that it modifies the current BBT inflationary period and predicts periods of "cosmic energy" or inflation. Otherwise its predictions are the same as the BBT. If further work is completed that can better quantify these parameters, it shows a lot of promise.
As an aside: One of the authors of the Open Letter and founder of the Alternative Cosmology Group is a friend of 20 years and an accomplished and highly respected cosmologist, author and scientist. Please don't be defensive of comments I make as I consider the back and forth discussions as a necessary part of the scientific process. Remember that it took many years of work and observations for the BBT to replace the "Steady State" universe.
CFB
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day CFB
You said
Please don't be defensive of comments I make as I consider the back and forth discussions as a necessary part of the scientific process. Remember that it took many years of work and observations for the BBT to replace the "Steady State" universe
Smile, me defensive, no way in hell.
Mate thats the name of the game discussion.
I just hope you read and read and try to understand.
Every theory has something to offfer.
If you are interested I will email you or post here more links.
The steady state has one problem, the production of new matter. That has been resolved by the cycling of matter.
I'm reading through some papers, maybe you maybe interested.
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chipdatajeffB
 - Joined on 07-16-2002
- Dallas area, Texas
- Posts 8,968
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Re: Origins of the Universe
 Harry Costas:
The steady state has one problem, the production of new matter. That has been resolved by the cycling of matter.
Well, yes and no. It has all the other problems plus that of continuous production of new matter. It is one step to grasp how the matter we see today (as well as that which must be there, but which we do not see) was produced at one time ... it is a rather large leap to grasp how it could be being produced continuously.
And as for "resolved", cycling is neither observed nor (with current technology) observable. Much like the brane concept.
Such things are fun to think about, however.
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CFB
- Joined on 11-04-2007
- Sterling, VA
- Posts 116
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Re: Origins of the Universe
Harry Costas:
Every theory has something to offfer.
I concur! This link is a synopsis of current theories and their pluses and minuses and I found it to be very balanced.
http://www.talkorigins.org/faqs/astronomy/bigbang.html
The papers you reference are interesting, but my feeling is that these theories are very early in their development. I'm inclined to let them develop.
I'm a simple observer, not a cosmologist and usually like to be told what the cosmology theory predicts should be observed. Newer instruments in development may shed light (no pun intended) on problems with BBT or maybe give the opportunity for a new theory to supplant it.
Regards,
CFB
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day from the land of ozzzzzzzzzz
I have read that link before. It read well but evidence lacks. Hey! do not take my word for it.
People who do not get involved with cosmology would have little choice in what to think.
Most papers and journals support the BBT.
Science when it comes to evidence and observations do not support the BBT.
To understand this, you will need to read and understand, if not just think along the BBT and that's OK.
If you want to keep on reading recent papers, just ask.
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day from the land of ozzzzzz
What do we know about expansion of the universe. How can space or a vacuum expand.
| http://arxiv.org/abs/0811.0981 |
| Model independent constraints on the cosmological expansion rate |
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| Authors: Edvard Mortsell, Chris Clarkson |
| (Submitted on 6 Nov 2008) |
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| Abstract: We investigate what current cosmological data tells us about the cosmological expansion rate in a model independent way. Specifically, we study if the expansion was decelerating at high redshifts and is accelerating now, without referring to any model for the energy content of the universe, nor to any specific theory of gravity. This differs from most studies of the expansion rate which, e.g., assumes some underlying parameterised model for the dark energy component of the universe. To accomplish this, we have devised new methods to probe the expansion rate without relying on such assumptions. |
| Using only supernova data, we conclude that there is little doubt that the universe has been accelerating at late times. However, contrary to some previous claims, we can not determine if the universe was previously decelerating. For a variety of methods used for constraining the expansion history of the universe, acceleration is detected from supernovae alone at >5 sigma, regardless of the curvature of the universe. Specifically, using a Taylor expansion of the scale factor, acceleration today is detected at >12 sigma. If we also include the ratio of the scale of the baryon acoustic oscillations as imprinted in the cosmic microwave background and in the large scale distribution of galaxies, it is evident from the data that the expansion decelerated at high redshifts, but only with the assumption of a flat or negatively curved universe. |
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day from the land of ozzzzz
Yet another interesting paper
| http://arxiv.org/abs/0709.4026 |
| Recycling Matter in the Universe. X-ray observations of SBS 1150+599A (PN G135.9+55.9) |
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| Authors: Gagik Tovmassian, John Tomsick, Ralf Napiwotzki, Lev Yungelson, Miriam Peña, Grazyna Stasińska, Michael Richer |
| (Submitted on 25 Sep 2007) |
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| Abstract: We present X-ray observations of the close binary nucleus of the planetary nebula SBS 1150+599A obtained with the XMM-Newton satellite. Only one component of the binary can be observed in optical-UV. New X-ray observations show that the previously invisible component is a very hot compact star. This finding allows us to deduce rough values for the basic parameters of the binary. With a high probability the total mass of the system exceeds Chandrasekhar limit and makes the SBS 1150+599A one of the best candidate for a supernova type Ia progenitor. |
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CFB
- Joined on 11-04-2007
- Sterling, VA
- Posts 116
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Re: Origins of the Universe
" Most papers and journals support the BBT. Science when it comes to evidence and observations do not support the BBT. To understand this, you will need to read and understand, if not just think along the BBT and that's OK. "
Harry,
I don't see the Tovmassian etal., article supporting or not supporting the BBT. This paper's primary interest is stellar evolution. It is an interesting paper, but how does it relate to the thread?
CFB
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day
The article is for information and therfore understanding of the workings of the parts within the universe. Knowing this one day we will be able to understand the origins or possibly the ongoings and the evolution of the universe via a cyclic process of the parts within the universe.
As for the BBT this will stay around for another couple of years if that.
Might as well add this link that I'm reading now. If I ever repeat any links, its because I re read them.
| http://arxiv.org/abs/0808.3767 |
| No large-angle correlations on the non-Galactic microwave sky |
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| Authors: Craig J. Copi, Dragan Huterer, Dominik J. Schwarz, Glenn D. Starkman |
| (Submitted on 27 Aug 2008) |
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| Abstract: We investigate the angular two-point correlation function of temperature in the WMAP maps. Updating and extending earlier results, we confirm the lack of correlations outside the Galaxy on angular scales greater than about 60 degrees at a level that would occur in 0.025 per cent of realizations of the concordance model. This represents a dramatic increase in significance from the original observations by the COBE-DMR and a marked increase in significance from the first-year WMAP maps. Given the rest of the reported angular power spectrum C_\ell, the lack of large-angle correlations that one infers outside the plane of the Galaxy requires covariance among the C_\ell up to \ell=5. Alternately, it requires both the unusually small (5 per cent of realizations) full-sky large-angle correlations, and an unusual coincidence of alignment of the Galaxy with the pattern of cosmological fluctuations (less than 2 per cent of those 5 per cent). We argue that unless there is some undiscovered systematic error in their collection or reduction, the data point towards a violation of statistical isotropy. The near-vanishing of the large-angle correlations in the cut-sky maps, together with their disagreement with results inferred from full-sky maps, remain open problems, and are very difficult to understand within the concordance model. |
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day from the land of ozzzz
Hello CFB
By the sounds of it in a way you know what you are talking about and have understanding.
How about going one more step and reading a little bit more on star formation and galaxy evolution.
By doing this you will gain insight into the cyclic processes that can be observed and explained.
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day from the land of ozzzzz
This is an interesting paper.
| http://arxiv.org/abs/0811.1688 |
| Effect of Central Mass Concentration on the Formation of Nuclear Spirals in Barred Galaxies |
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| Authors: Parijat Thakur, H.B. Ann, Ing-Guey Jiang |
| (Submitted on 11 Nov 2008) |
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| Abstract: We have performed smoothed particle hydrodynamics (SPH) simulations to study the response of the central kiloparsec region of a gaseous disk to the imposition of nonaxisymmetric bar potentials. The model galaxies are composed of the three axisymmetric components (halo, disk, and bulge) and a non-axisymmetric bar. These components are assumed to be invariant in time in the frame corotating with the bar. The potential of spherical $\gamma$-models of Dehnen is adopted for the bulge component whose density varies as $r^{-\gamma}$ near the center and $r^{-4}$ at larger radiiand hence, possesses a central density core for $\gamma = 0$ and cusps for $\gamma > 0$. Since the central mass concentration of the model galaxies increases with the cusp parameter $\gamma$, we have examined here the effect of the central mass concentration by varying the cusp parameter $\gamma$ on the mechanism responsible for the formation of the symmetric two-armed nuclear spirals in barred galaxies. Our simulations show that the symmetric two-armed nuclear spirals are formed by hydrodynamic spiral shocks driven by the gravitational torque of the bar for the models with $\gamma = 0$ and 0.5. On the other hand, the symmetric two-armed nuclear spirals in the models with $\gamma=1$ and 1.5 are explained by gas density waves. Thus, we conclude that the mechanism responsible for the formation of the symmetric two-armed nuclear spirals in barred galaxies changes from the hydrodynamic shocks to the gas density waves when the central mass concentration increases from $\gamma = 0$ to 1.5. |
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GaryAKent
 - Joined on 01-22-2008
- Fall Creek, Wisconsin
- Posts 15
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Re: Origins of the Universe
Undoubtedly, there will be more progress in the physicodynamics of galaxy formation. Once discrete large scale structures begin to form in the universe, the assumption of the cosmological principle that the universe is homogeneous and isotropic begins to break down. But, before this time, it was probably perfectly appropriate.
I have never seen a mathematical model of the "origin" of the universe and its evolution, growth and development carried through to the present era and beyond. Such a model has been inferred from the data, but I don't think it has been explicitly expressed. Using Guth's inflationary scenario, specifically his premise of an exponential burst of growth near the very beginning, I have developed a mathematical model that is capable of depicting the evolution of the universe from 10 ^ -60 sec to 30 gigayears and beyond.
By using various choices for parameter values, it is possible with this model to represent a universe that apparently follows a trajectory true to empirical data and transitions to a new era of "neo-inflation" or dominance by dark energy. Or, it can move toward a period of deflation and collapse or toward "flat" expansion at a constant rate. Adjustable parameters make it possible to mimic any empirically determined behavior with but very few input values.
I use Einstein's natural units to represent the "radius" or radius of curvature of the universe, time and the speed of light. This is the only way that Guth-like equations make any sense and are definable. A plot of these equations, their 1st and 2nd derivatives, H and the expansion of the universe if it expanded at the speed of light, seems to show a sort of symmetry. The existence and positions of multiple intersection points where these curves cross in interesting ways portrays an array that might be interpreted as a representation of several kinds of invariance.
I am tempted to interpret this symmetric array of intersections as a highly symmetric matrix of invariances bespeaking various fundamental constants according to Noether's Theorem. But, There is an interesting problem.
I refer to my equations as empirical or phenomenological models that are based fundamentally on theory so that it should be possible to extrapolate successfully into the past and future alike. Using parameters that give a result consistent with the onset of a new epoch of inflation in "recent" times, the model does not provide an early time when the nascent universe could have equilibrated. Essentially, Guth's idea is that equilibration occurred during the exponential induction period when the universe was very small and that the transition to exponential growth locked in the homogeneity that had been achieved.
But, with the choice of parametric values giving the required result of new inflation, there is no induction period. And, because there are fewer multiple intersection points displayed by this type of plot, it displays less of the above described symmetry than a plot of a type that displays developmental deceleration. Plots showing deceleration show higher "symmetry" and they provide a type of induction period in the traces of their curves.
I want to combine the two types of equations by merely adding them together with variable weighting factors as is done with hybrid solutions to a quantum wave equation. The weights might themselves follow a simple equation that emphasizes the deceleration scenario in the first few moments of the universe's existence and the acceleration scenario later in the evolutionary trajectory of then universe. Then, the induction period would be preserved while the transition to new inflation is allowed. I want to see if my special symmetry is preserved.
Of course, if the universe really did originate with a singularity, no induction period would be required. Guth's inflation might not be needed after all. If the trajectories of all waves and particles originated at the same point, they would progress with at least some of the same "original" intensive properties, like temperature. The origin of the universe was not an explosion. It is unnecessary to postulate any form of turbulence that might give rise to inhomogeneities that would need to be suppressed or quenched. Precisely what cause could be cited that would result in an uneven expansion of space-time or a turbulent beginning with temperature variations? Are not temperature variations simply assumed? Why?
Gary Kent
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Harry Costas
- Joined on 04-05-2008
- Posts 204
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Re: Origins of the Universe
G'day Gary
A model is a like a black box computer. Feed it what you think will produce a model.
So! To over come this, research Star and galaxy evolution and transient changes that are involved in the evolutiion.
There are many simulations, if you want a few links, just ask.
In my opinion the best model is a recycling model.
As for the BBT model, you can go around in circles with it.
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