[Pluto]

G'day from the land of ozzzzz

Hello reason

you said

My understanding is that this theory has been abandoned since it was discovered that universal expansion is "speeding up" instead of decelerating.

No, I do not think it has been abandon. The recycling process is part of the ongoing processes, we can study and observe such processes.

When you talk about expansion speeding up, do you mean spce/time or actual distances?


[0801.2965] Cosmology and Cosmogony in a Cyclic Universe
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.

[REASON]

Originally Posted by Pluto

When you talk about expansion speeding up, do you mean space/time or actual distances?

I think we are talking about the rate at which objects (galaxies) are moving away from one another.

Ever since two teams of astronomers announced in 1998 that the expansion of the universe appeared to accelerating with time, other teams of astronomers have been double-checking their conclusions with data from other sources. Although some astronomers still have doubts about the accelerating universe, evidence in its favour continues to grow. The latest comes from studies of the deviation of galaxy velocities from a smooth universal expansion (I Zehavi and A Dekel 1999 Nature 401 252).

More evidence for the accelerating universe - physicsworld.com


Here is an interesting slide presentation with lots of information.

The Accelerating Universe,Inflation, & the Dark Energy


And another article in an April 2003 edition of Physics Today by Saul Perlmutter

For millennia, cosmology has been a theorist’s domain, where elegant theory was only occasionally endangered by inconvenient facts. Early in the 20th century, Albert Einstein gave us new conceptual tools to rigorously address the questions of the origins, evolution, and fate of the universe. In recent years, technology has developed to the point where these concepts from general relativity can be substantiated and elaborated by measurements. For example, measurement of the remnant glow from the hot, dense beginnings of the expanding universe—the cosmic microwave background—is yielding increasingly detailed data about the first half-million years and the overall geometry of the cosmos (see the news story on page 21 of this issue).

The standard model of particle physics has also begun to play a prominent role in cosmology. The widely accepted idea of exponential inflation in the immediate aftermath of the Big Bang was built on the predicted effect of certain putative particle fields and potentials on the cosmic expansion. Measuring the history of cosmic expansion is no easy task, but in recent years, a specific variety of supernovae, type Ia, has given us a first glimpse at that history—and surprised us with an unexpected plot twist.

http://www.supernova.lbl.gov/PhysicsTodayArticle.pdf


This understanding of the accelerating expansion of the universe over the last decade has brought about the theories concerning "Dark Matter" and "Dark Energy" which are used to explain the apparent repulsive force that is causing the acceleration.

If the acceleration remains constant, then there is no likelyhood of an eventual collapse as in a cyclic universe.

But, that's a big if.

[Pluto]

G'day from the land of ozzzzzzz


Reason said

I think we are talking about the rate at which objects (galaxies) are moving away from one another.

Mate if you are thinking actual distance than I think you are mistaken. The BBT relies on space/time for the expansion and not actual distance of local galaxies , but of the super structures that hold clusters of clusters of galaxies.

Thank You for the above links I will read them.

[CraigD]

Originally Posted by Pluto

Please show me the observed data that supports the BBT and implies a start throughout the universe.

The most basic and well-know observed data that support the Big Bang model are the abundance of isotopes of elements and the spectrum of the cosmic microwave background radiation. These data are numerous, spanning many years, observatories, and observations – I recommend reading them by following the referenced from well-known textbook or encyclopedias, such as the wikipedia article section “Observational Tests and Status of BBN”. I especially like the hands-on presentation of the results of the dauntingly technical calculations of SBBN (Standard Big Bang Nucleosynthesis) at this referenced webpage.

An important success of the Big Bang model is that, in addition to experimentally measurable laws of nature, the abundance of elements and the CMBR both depend on the ratio of baryons (which consist mostly of protons and neutrons, the particles accounting for most of the observed mass of the universe) to photons (the particles accounting for all electromagnetic radiation, including the CMBR), a number usually referred to by the Greek letter (“eta”). If the ratio predicted by the observed spectrum of the CMBR differed greatly from that predicted by SBBN.

While these and other successful predictions of the Big Bang model have made it and its variants the most widely accepted cosmological model of present time, the characterization of its success as high precision across all possible observed data is a mischaracterization. Most notably, the direct measurement of eta from the visible mater in the univers is roughly a power of ten smaller than that required by SBBN and the CMBR. This is the famous “missing matter problem” that nearly all living astrophysics students have grown up with.

Were there no evidence of this missing matter actually existing, the Big Bang model would, I think, be less popular. However, a lot of evidence in the form of such data as the speed of stars relative to their galactic centers (see Galaxy rotation curve - Wikipedia, the free encyclopedia), suggests that the matter exists, but is not visible – that is, that it is “dark”.

Originally Posted by Pluto

and if possible explain to me how matter recycles.

As previous posts in this and other threads have noted, the Big Bang model doesn’t describe conditions before the first of its periods, the grand unification epoch. Therefore it isn’t itself a “cyclic model” doesn’t predict that “matter recycles” – that is, that the abundance of the elements is constant, or will return at some future time to its past values. How the various cyclic theories predict it differ greatly. To discuss them, I need to summarize, to the best of my ability, the main classes of cyclic models:

• Large scale vacuum energy fluctuation theories. These speculative theory (previously discussed in posts such as “Vacuum fluctuation vs. "instability of zero" hypotheses”) proposes that, very, very rarely, the beginning of a big bang universe spontaneously appears in effectively empty space - or, as Edward Tryon put it in his 1973 Nature article, “Our Universe is simply one of those things that happens from time to time.”
  
  Under these theory, in the effectively infinite time around the predicted heat death of the universe, a big bang spontaneously occurs.
• Big bounce theories.
  
  Under these theories, despite present-day observations suggesting it is not the case, the universe is actually gravitationally closed. At some future time, the universe stops expanding, and begins contracting, eventually returning to a hot, dense “big crunch”, a state that recreates the initial conditions of a big bang.
• “Outside influence” theories. These theories, or which brane theory is one, involve the introduction of matter and energy from outside of the conventionally observable universe.
  
  Under these theories, which are arguably not truly “cyclic”, big bangs or similar universe-starting events are actually due to events in a “larger universe”, such as the higher-dimensional space of brane theory, black holes in other universes, etc.
• Time travel theories. These theories propose that, at some time in the universe’s future, natural or artificial phenomena send matter and energy into the past. They propose a violation of mass-energy conservation. To the best of my knowledge, despite having been championed by various well-known physicists, these theories remain essentially science fiction, because no experiment to confirm or refute any of them has been proposed.
• Negentropy theories. These theories involve processes in which, due to some sort of effects outside of the usual laws of physics, entropy statistics are violated on a large scale. To the best of my knowledge, despite widespread popularity in the humanities and scientific disciplines outside of physics, these theories are pseudoscience, not only not making testable experimental predictions, but either offering no explanation of the effects that make them work, proposing explanations that specifically exclude the possibility of scientific testing, or propose explanations with experiments that have actually been conducted and refuted the explanations.

[coldcreation]

Good day from the land of bullllll.

Originally Posted by CraigD

...An important success of the Big Bang model is that, in addition to experimentally measurable laws of nature,...

To which laws of nature do you refer here?

Originally Posted by CraigD

While these and other successful predictions of the Big Bang model have made it and its variants the most widely accepted cosmological model of present time, the characterization of its success as high precision across all possible observed data is a mischaracterization. Most notably, the direct measurement of eta from the visible mater in the univers is roughly a power of ten smaller than that required by SBBN and the CMBR. This is the famous “missing matter problem” that nearly all living astrophysics students have grown up with.

This is precisely the reason why opponents to big bang cosmology think the theory in untenable and should be discarded. Learning about a problem in school and living with it doesn't make it real. A scientific theory in any other field of physics, if it proved to be this far off-track, would be abandoned on the spot. Only in cosmology (also, to some extent astrophysics, Edit: and astronomy) could a theory that diverges from observational data to such an extent survive.

Originally Posted by CraigD

Were there no evidence of this missing matter actually existing, the Big Bang model would, I think, be less popular. However, a lot of evidence in the form of such data as the speed of stars relative to their galactic centers (see Galaxy rotation curve - Wikipedia, the free encyclopedia), suggests that the matter exists, but is not visible – that is, that it is “dark”.

Edit: This could be evidence too that something else (in addition to standard baryonic dark matter: brown dwarfs, etc.) is responsible. I hope the search continues.

Originally Posted by CraigD

Under these theories, despite present-day observations suggesting it is not the case, the universe is actually gravitationally closed. At some future time, the universe stops expanding, and begins contracting, eventually returning to a hot, dense “big crunch”, a state that recreates the initial conditions of a big bang.

Indeed, one would think that the SNe Ia data implies an open universe that expand forever and accelerates while doing so, leading not to a big crunch but to a Big Rip.

Indeed too, with parameters such as nonbaryonic dark matter and dark energy, the data can be taylored to fit just about any model. Or, I should say, the theory can be taylored to fit just about any data.


CC

[Pluto]

G'day from the land of of ozzzzzz

CraigD used words that could sell anything and yet mean very little.


Coldcreation has hit the nail on the head:

This is precisely the reason why opponents to big bang cosmology think the theory in untenable and should be discarded. Learning about a problem in school and living with it doesn't make it real. A scientific theory in any other field of physics, if it proved to be this far off-track, would be abandoned on the spot. Only in cosmology (and to some extent astrophysics) could a theory that diverges from observational data to such an extent survive.

I do not have to prove that the Big Bang or any alternative theory is correct. I'm not equiped to do so. But! being half blind does not mean that science goes walking. Scientific evidence takes priority over so called evidence that cannot stand up and be counted.

For years I have been asking this simple question.

How can over 100 Billion galaxies in varies stages, in deep field images 13.2 Gyrs form in just 500 million years?

Please answer this without adhoc ideas.

[Little Bang]

CC a question. You of course never try to make the data fit your on ideas? I have but usually change my ideas to fit the data.

[Pluto]

G'day from the land of ozzzzzzzzzz

Everytime I read a paper, I like to share its info and if possible get a feedback from some person.

[astro-ph/0601171] Is space really expanding? A counterexample

Is space really expanding? A counterexample

Authors: Michal Chodorowski (Copernicus Center)
(Submitted on 9 Jan 2006 (v1), last revised 3 Jul 2006 (this version, v2))

Abstract: In all Friedman models, the cosmological redshift is widely interpreted as a consequence of the general-relativistic phenomenon of EXPANSION OF SPACE. Other commonly believed consequences of this phenomenon are superluminal recession velocities of distant galaxies and the distance to the particle horizon greater than c*t (where t is the age of the Universe), in apparent conflict with special relativity. Here, we study a particular Friedman model: empty universe. This model exhibits both cosmological redshift, superluminal velocities and infinite distance to the horizon. However, we show that the cosmological redshift is there simply a relativistic Doppler shift. Moreover, apparently superluminal velocities and `acausal' distance to the horizon are in fact a direct consequence of special-relativistic phenomenon of time dilation, as well as of the adopted definition of distance in cosmology. There is no conflict with special relativity, whatsoever. In particular, INERTIAL recession velocities are subluminal. Since in the real Universe, sufficiently distant galaxies recede with relativistic velocities, these special-relativistic effects must be at least partly responsible for the cosmological redshift and the aforementioned `superluminalities', commonly attributed to the expansion of space. Let us finish with a question resembling a Buddhism-Zen `koan': in an empty universe, what is expanding?

[coldcreation]

Interesting link Pluto. I saved it to my desktop and have read through it quickly. I'll look at it in more detail soon. (That link could have gone in the Redshift z thread too for discussion, but it fine here). Do you have any comment about it?

Originally Posted by Little Bang

CC a question. You of course never try to make the data fit your on ideas? I have but usually change my ideas to fit the data.

Ok Little Bang. Here's the scoop:

Certainly, if a new observation comes in, anyone with a theory related to the observation will see how it fits in (if indeed it does). If it does not, there is a problem. Chances are the theory would have to be discarded, or changed drastically; especially if, to justify the new observation, you had to invent something new, like CDM, as a general modification.

A theory make predictions. If observations contradict those predictions, the theory is either modified, adjusted (based on those observations), or it is discarded and replaced with another theory.

On topic: The pre-1998 standard model (the Friedmann model) had three possible geometries: open, closed or flat. Flatness was favored for a variety of reasons.

When the SNe Ia data began to be taken seriously (i.e., when the data was confirmed) a general modification was made to the standard Friedmann model. The new standard model (Lambda-CDM) had to include CDM and DE, in abundant quantities.
The terms open, closed or flat no longer had any meaning, since the parameters (there are six all together) could be adjusted to achieve the desired geometry. Recall, inflation predicted a flat universe. If the universe wasn't flat then inflation had to be discarded. And hello problems.

Of the pre-1998 standard model geometries (without CDM and DE) the closest approximation to the SNe Ia data was an open universe (shaped like a saddle). It was not the Friedmann prediction though, since the open Friedmann model simply expanded to infinity without slowing down (and neither did it accelerate). But an open universe meant that inflation was no longer viable, thus all the problems associated with big bang cosmology that inflation had solved (the horizon problem, the flatness problem, the galaxy problem, the antimatter problem, the entropy problem, etc) were back on the table.

The universe had to be flat. Because without inflation the big bang could no longer absorb the irreconcilable difficulties against which it was faced. It would have basically had to be abandoned.

Thanks to the adjustable parameters flatness could be achieved (or even 'closedness'), and the big bang theory was saved, at least for the time being.

If the LHC can shed light on CDM that that will be one less problem for the Lambda-CDM model. I doubt anything related to CDM will materialize, it could though. But then there is remaining DE problem; something destined to remain obscure, by definition, even in principle.



CC

[Pluto]

G'day from the land of ozzzzzzz


Coldcreation said

Interesting link Pluto. I saved it to my desktop and have read through it quickly. I'll look at it in more detail soon. (That link could have gone in the Redshift z thread too for discussion, but it fine here). Do you have any comment about it?

If redshift is in conflict and is in error, than more research should be done to give us a better understanding.

http://en.wikipedia.org/wiki/Hubble%27s_law

Hubble's law is the statement in physical cosmology that the redshift in light coming from distant galaxies is proportional to their distance. The law was first formulated by Edwin Hubble and Milton Humason in 1929[1] after nearly a decade of observations. It is considered the first observational basis for the expanding space paradigm and today serves as one of the pieces of evidence most often cited in support of the Big Bang.

Than Hubble's law would be in question, than the BBT would be in question, than mainstream thinking would be in question. That would rock the boat going down main stream.

I do not understand why the BBT has to be saved.