Talk:Non-standard cosmology

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Disruption

If the person(s) consistently disrupting this article through the IP 84.158.2xx.xxx do not stop this, I will report them to the administrators for a general block. Normally warning would be placed on the user pages, but since this is a dynamical IP, I'm placing it here. --ScienceApologist 14:40, 13 June 2007 (UTC)

Non standard means nothing but Dark Ages

Tens of pages of chats, to hide this. Have fun with Dark matter and Dark energy, produced by the highly standard "Standard model". That's tautologic. —Preceding unsigned comment added by 83.103.38.68 (talk) 13:38, 11 March 2008 (UTC)

Why the last "undo"?

(Comparison of the two versions). The major flaws I can spot in the last version prior to the undo was the wording "non-standard/ alternative cosmology" instead of just "non-standard", and "the big bang model(s)" instead of "the big bang". Just because the dash and a plural indicated between parenthesis just look somewhat ugly. It could be fixed with something "non standard [cosmologies] or alternative cosmologies" and "big bang models", respectively. Other than that, is there something really faulty with the penultimate (Forrestnoble's) edition? I don't really know the subject very deeply, so I have no idea about the quality entire new section added. The rest were some sort of wordings that, in my point of view, just improved the NPOV, without being innacurate in any sense. --Extremophile (talk) 04:15, 28 August 2008 (UTC)

I support the last undo. The subject is a bit tricky because it falls squarely under the WP:FRINGE guideline. We are charged with discussing those "alternatives" to the Big Bang according to the WP:WEIGHT they receive in mainstream sources. If we were to follow the letter of the law, the vast majority of this article would be on the steady state theory since that is the one that is by far the most prominent of the non-standard cosmologies. However, we make some accommodations for those ideas which are still around and bumping on the internet and to a lesser extent, the scientific community: e.g. MOND, Hoyle & Narlikary, plasma cosmology, etc. The issue with the previous edit is twofold: one) non-standard cosmologies are not in direct competition any longer with the Big Bang. We essentially have a situation where the most prominent non-standard cosmologies are prominent for historical reasonsa and are not in direct competition. two) the non-standard cosmologies that do have contemporary proponents are so marginalized as to be almost unworthy of mention. We must do our best to let readers know of this situation. ScienceApologist (talk) 16:21, 28 August 2008 (UTC)

The section on WP:WEIGHT says that "minority views can receive attention on pages specifically devoted to them, [and such] a view may be spelled out in great detail". So as long as we say there is a mainstream view, and do not pretend that the fringe view is more widespread than it really is, then NPOV and WP:WEIGHT are maintained. I agree that there would be a problem if the text was part of an article on a mainstream subject, such as the Big Bang, or Physical Cosmology. --Grburster (talk) 17:39, 28 August 2008 (UTC)

There is weight, and then there is weight. Here we write a summary article on EVERY non-standard cosmology that is encyclopedic. Which ones deserve the most weight? Probably the most famous ones. Ergo the comment on steady-state theory. ScienceApologist (talk) 17:49, 28 August 2008 (UTC)

In an article on cosmologies, you are right that the most famous and acceptable one gets the most weight. In an article specifically on one non-standard cosmology, WP:WEIGHT says that such "a view may be spelled out in great detail". In this article, I would not expect the Big Bang to get much coverage because it is not a non-standard cosmology. But we still mention it, and link people to the main article. --Grburster (talk) 21:28, 28 August 2008 (UTC)

Yes. I think this article does a pretty good job of doing that. Do you disagree? ScienceApologist (talk) 15:35, 29 August 2008 (UTC)

Fundamental Assumptions:

Aren't we missing the assumption that all the mass in the universe is contained in a finite volume of space? Without that, there would be no large-scale warping of space-time and no singularity at the beginning of time. --Onerock (talk) 01:46, 13 August 2009 (UTC)

Actually, we're not making that assumption. Warping of space locally is based on the density of matter, not the absolute amount present. Warping of space on the scale of the universe requires that the universe have a given average density, not that its mass be confined to any finite volume (just that any finite volume have about the right amount of mass in it).

Regarding a singularity, this refers to the density of the universe approaching infinity some finite amount of time in the past. It doesn't imply that the entire universe collapses to a point; just that the parts that we presently observe (a finite-sized region) were once contained within an arbitrarily small volume.

I hope this helps answer your question. --Christopher Thomas (talk) 02:21, 13 August 2009 (UTC)

Christopher; on the matter of the singularity, we seem to be in agreement in principle, though I disagree with your semantics. The term “singularity” originally meant a finite mass contained in zero volume. Perhaps some proponents of the Big Bang model are trying to reverse earlier statements without contradicting them by redefining the word “singularity”.

I am no mathematician, but I know that warping of space-time is a function of the gradient of gravitational potential. If the universe is infinite, and if the distribution of matter is isotropic and homogeneous, then the gravitational potential is the same everywhere. Except for local fluctuations due to clumping of matter, the potential IS the same everywhere, and the gradient is zero everywhere—unless the universe is finite.

I am familiar with the mathematical proof that gravity inside a hollow spherical shell of homogeneously distributed mass is zero; also that gravity outside such a shell is equivalent to the total mass concentrated at a point in the center. (These proofs are mathematically valid, though we should keep in the back of our minds that the physical reality of them depends on the validity of Newton’s universal law of gravitation all the way to infinity, which can never be proven.) I believe what has been overlooked is the gravity inside a sphere of homogenously distributed matter from which a smaller sphere has been removed—the surface of said smaller sphere including the center and being tangent to the surface of the larger sphere. The gravity of this larger sphere exactly cancels the gravity of the smaller sphere.

If the universe is infinite, homogeneous and isotropic, then there is always going to be a larger sphere, as described above, twice the radius of the one whose gravity is being used to calculate the warping of space-time; and gravity from beyond that larger sphere is zero. So Einstein’s derivation of the large-scale warping of space-time, based only on the density of the universe, is fallacious. Onerock (talk) 19:19, 20 August 2009 (UTC)

Actually, the term "singularity" refers to any mathematical singularity in solutions to the equations of general relativity. When applied to a gravitational singularity, the resulting ill-behaved region is usually either point-like or ring-like, but Schwarzschild's original treatment of black holes in GR had the singularity at the event horizon (due to the coordinate system he chose for the solution). Whether you consider the singularity at the beginning of time to be a gravitational singularity or not is a matter of taste (density and spacetime curvature approach infinity if I understand correctly, but it's very different from what you get inside black holes).

With regards to the potential, it turns out to be very difficult to define "gravitational potential energy" in curved spacetime. When space is approximately Euclidean, you can approximate things with Newtonian gravity, define potential energy, and take the gradient to get force, but this should not be confused with finding the "warping of spacetime". Similarly, your statements about spherical shells hold only in the weak-field approximation (where gravity looks Newtonian). You are correct in concluding that a universe with Euclidean spacetime obeying Newtonian gravity would not be able to act in the way described.

For more information about the equations governing general relativity, see Einstein field equations. For information about a description of the expanding universe, see de Sitter universe, de Sitter space, and metric expansion of space. A solution that describes the dense early universe as well as the later universe would be the Friedmann equations. For a more detailed discussion of the topic, perhaps try Wikipedia:Reference desk/Science, as my math isn't good enough to solve the field equations for you (though some solutions are already given in the links supplied above). --Christopher Thomas (talk) 20:34, 20 August 2009 (UTC)

Change the Title of the Article

The pejorative title "Non-Standard" should be changed to this neutral wording which already exists in wikipedia articles: Alternative cosmological models. Change the title to "Alternative cosmological models". 173.169.90.98 (talk) 23:23, 16 May 2010 (UTC)

We've already established consensus for this title. You must deal substantively with the winning arguments of this archived discussion and this one in order to reopen debate on this topic. ScienceApologist (talk) 23:00, 17 May 2010 (UTC)

Who is we ? I never saw any discussion of the title being inappropriate.173.169.90.98 (talk) 23:17, 17 May 2010 (UTC)

WP:RTA. ScienceApologist (talk) 23:20, 17 May 2010 (UTC)

So where was the title supposedly ever agreed upon by any consensus ? 173.169.90.98 (talk) 23:24, 17 May 2010 (UTC)

The basic point is that non-standard cosmologies are those which are different from the standard Lambda-CDM model and other tweaks to it. "Alternative cosmologies" can involve some models which are still "standard" by the strict definition of having a hot Big Bang. E.g. Quintessence (physics). ScienceApologist (talk) 23:26, 17 May 2010 (UTC)

It remains that "non-standard" is pejorative and should be changed. 173.169.90.98 (talk) 23:29, 17 May 2010 (UTC)

How is it "pejorative"? The "standard" is the one that everybody uses. These are, at best, tiny minority proposals. ScienceApologist (talk) 23:31, 17 May 2010 (UTC)

Non-standard is clearly pejorative, like saying sub-standard. The big bang people use the term to denigrate opposing views. 173.169.90.98 (talk)

We're not here to right great wrongs. I'm sorry, but Wikipedia follows the prejudices of the world. If you don't like it, try to get the community to change their terminology. The place to fight this battle is not on Wikipedia. ScienceApologist (talk) 23:38, 17 May 2010 (UTC)

No logic to that. How about articles about Blacks that would use the N-word as the title, because that is historically the word used by Mark Twain and everyone else in history. 173.169.90.98 (talk) 23:41, 17 May 2010 (UTC)

I'm sorry you feel that this is illogical, but it is the consensus of the Wikipedia community. You can discuss the problems with this approach at various locations including, for example, the village pump. ScienceApologist (talk) 23:44, 17 May 2010 (UTC)

Who is the community ? you ? The title is misleading and pejorative and should be discussed by more than you. 173.169.90.98 (talk) 23:46, 17 May 2010 (UTC)

By all means please ask for a third opinion. ScienceApologist (talk) 23:48, 17 May 2010 (UTC)

Do not censor published sources

The two Physics Essays references are newly published (June 2010), it is impossible for them to have independent recognition so quickly, but do not censor them, wikipedia uses many brand new published articles, these are not the first. Also, most references cited in wikipedia are never cited by other articles. If you censor with that reasoning there would be nothing left in wikipedia. 173.169.90.98 (talk) 23:11, 17 May 2010 (UTC)

WP:FRINGE#Independent sources, WP:CBALL, WP:RECENTISM, and WP:NOTPAPER are all relevant. We don't use "brand new published articles" until there is critical reception of them found. There are literally hundreds of tiny minority ideas floating around in the fringe literature. Only the most WP:PROMINENT ones deserve mention in Wikipedia. If you want to see those ideas listed here, encourage the astronomy and physics community to review those papers. ScienceApologist (talk) 23:22, 17 May 2010 (UTC)

They were both reviewed, peer-reviewed. Also, it is not wikipedia policy to censor minority views, as long as they are in peer-reviewed mainstream journals you cannot censor them because you don't like what they say. 173.169.90.98 (talk) 23:27, 17 May 2010 (UTC)173.169.90.98 (talk) 23:25, 17 May 2010 (UTC)

Physics Essays is not peer-reviewed in the usual sense because authors can ignore reviewers' comments. But even if they were reviewed in the best journal, if nobody noticed them and there are no citations to them by outside reviewers they do not belong in Wikipedia because it is impossible to write a reliably sourced neutral article or section of an article on them. If you want to see them included, the best thing you can do is encourage someone to review the articles and publish their reviews in reliable sources so we can use them. See WP:PSTS. ScienceApologist (talk) 23:28, 17 May 2010 (UTC)

You try publishing there and ignore the reviewers, that is absurd. It is a mainstream peer-reviewed journal. 173.169.90.98 (talk) 23:35, 17 May 2010 (UTC)

You're missing the major point: we cannot use the source because no one else has cited it yet. We have only the author's say-so to go on and that is not good enough for Wikipedia's standard of WP:PSTS. ScienceApologist (talk) 23:37, 17 May 2010 (UTC)

Most articles are NEVER cited by other papers, especially articles that big bang people would rather avoid. You cannot censor on that basis. 173.169.90.98 (talk) 23:39, 17 May 2010 (UTC)

I acknowledge that it is a standard to which it is difficult to rise, but it is the standard that was agreed to when Wikipedia formed it's policies and guidelines. If you want to change that standard, you should consider discussing it at the talk pages of the policy, for example: WT:PSTS. ScienceApologist (talk) 23:46, 17 May 2010 (UTC)

You are clearly incorrect - wikipedia uses many published articles that were never cited by others, especially new articles. 173.169.90.98 (talk) 23:48, 17 May 2010 (UTC)