Talk:Universe

Exists -> Existance

I noticed that the Exists link goes to Existential quantification, but I wonder if Existence would be a better link?

Removed link

I removed a link to http://cseweb.ucsd.edu/~gill/Lat_Intro.htm — I don't think it is appropriate here. Feel free to discuss. — Knowledge Seeker দ 03:28, 5 May 2010 (UTC)

Maybe it made sense in the context? It sure doesn't seem to fit, so good call. Jminthorne (talk) 05:02, 7 May 2010 (UTC)

Removed fact tag from "Size, age, contents, structure, and laws"

The possibility that the universe may be infinite in size is mentioned in the reference at the end of the sentence (Misconceptions about the Big Bang), so I took it out in my last edit. Jminthorne (talk) 05:01, 7 May 2010 (UTC)

What about splitting the entry?

I came to the Universe page searching for scientific theories about its origin, and then I was lost on myths, religion and philosophy. It is not only a summary, it is a true blend - myths, religion, philosophy and science in every section. What about a separated "Universe in science" entry? —Preceding unsigned comment added by 81.38.177.146 (talk) 10:32, 27 May 2010 (UTC)

no mention of dodecahrdron multiverse

i have added a seperate article in the end about a dodecahedron multiverse.plz help in expanding the article and if possible a seperate article here are some links http://en.wikipedia.org/wiki/Poincar%C3%A9_dodecahedral_space#Poincar.C3.A9_homology_sphere —Preceding unsigned comment added by Manchurian candidate (talk • contribs) 05:06, 6 June 2010 (UTC) http://goldennumber.net/classic/universe.htm http://news.nationalgeographic.com/news/2003/10/1008_031008_finiteuniverse.html http://physicsworld.com/cws/article/news/18368 http://en.wikipedia.org/wiki/Wilkinson_Microwave_Anisotropy_Probe http://en.wikipedia.org/wiki/Dodecahedron http://arxiv.org/abs/0801.0006 manchurian candidate 04:54, 6 June 2010 (UTC) —Preceding unsigned comment added by Manchurian candidate (talk • contribs)

Definition

I've searched over 40 dictionaries at http://onelook.com/?w=universe&ls=a and only 2 mentioned time in the definition: wiktionary (not a reliable source) and one other that appeared to be a mirror. The idea that future time is included in a definition of the universe projects a deterministic POV that is in no way generally supported in the literature, much less being indisputable.

A good article uses defs from reliable sources, ones that are presented as defs - not as a description of a diagram on p84, volume 742 of some technical work, and not unreliable ones that are telling us how to have better karma. Here's an attempt to express a def that is more generally agreed upon. It does not list all things that are included. It does not say time & space are part of the universe and it does not say they are not. If one does think it means anything to say time & space "exist", then one can consider them to be included by "everything that exists".

The Universe comprises the totality of everything that exists, including all physical matter and energy, the planets, stars, galaxies, and the contents of intergalactic space.

Btw, the previous def had other problems also. The meaning of "universe" clearly includes all things that exist, whether they are perceived or not.--JimWae (talk) 19:25, 8 June 2010 (UTC)

By saying all physical matter is included, instead of:

The universe comprises everything perceived to exist physically...

we do not seem to exclude the "non-physical" world (whereas "comprise" often means a presentation of an exhaustive list of components follows). While this article deals primarily with the cosmos, if "universe" truly includes everything, it also includes non-physical "things" like the number system that living things have devised (though this article does not need to focus on every non-physical "thing" that exists) --JimWae (talk) 19:51, 8 June 2010 (UTC)

There is a little problem. Defining the universe as the "totality of everything that exists" begs the question "... that exist according to whom?" Different observers have a different notion of time, so they have a different notion of existence. Some thing (e.g. a particle) that exists according to you might not exist according to me yet. So your universe differs from mine. That problem is removed by replacing the space notion with the space-time notion, as was done in Basa, page 84. You object that this imposes deterministism POV. I don't agree. Events still to happen (and thus undetermined) according to you, might allready have happened (and thus been determined) according to me. And of course, events not happened (yet) according to anyone, need not happen, so to speak. I think the only way not to run into trouble, would be by defining the universe such that it includes every possible or conceivable event, as was implicitly done in the previous version. As it is stated now, the universe is relative. Any idea how we could fix that? DVdm (talk) 20:15, 8 June 2010 (UTC)

after edit conflict: We do not need to determine who all are Democrats to say what democracy is. We do not need to determine all of what truly exists, for people to agree that, whatever one thinks exists, it is part of what one means by "universe". We may disagree about the contents of the universe without disagreeing on how to use the word. Saying space & time are part of the universe taking a disputed position on what the contents of the universe are - it is not necessary to take a position on this to give a reliable & generally accepted def. There is no reliable source for including space & time (much less FUTURE time) - and even if a few sources were to be found, it is still not generally accepted. An encyclopedia is not supposed to be going out on limbs presenting novel & not-generally accepted formulations of the state of current knowledge--JimWae (talk) 20:26, 8 June 2010 (UTC)

I agree. Including the entire future would go flatly against the many hundreds of publications talking about "The Future of the Universe". Still, for me, the relativity problem remains. But no worries, I will not lose any sleep over it. I guess this is one of those subjects best to be referenced by a few good old dictionaries. The lead is much better now than it was before. DVdm (talk) 20:36, 8 June 2010 (UTC)

Misuse of sources

A request for comments has been filed concerning the conduct of Jagged 85 (talk · contribs). Jagged 85 is one of the main contributors to Wikipedia (over 67,000 edits, he's ranked 198 in the number of edits), and practically all of his edits have to do with Islamic science, technology and philosophy. This editor has persistently misused sources here over several years. This editor's contributions are always well provided with citations, but examination of these sources often reveals either a blatant misrepresentation of those sources or a selective interpretation, going beyond any reasonable interpretation of the authors' intent. I searched the page history, and found 15 edits by Jagged 85 in July 2008 and 9 more edits in Mach 2010. Tobby72 (talk) 20:45, 8 June 2010 (UTC)

That's an old and archived RfC. The point is still valid though, and his contribs need to be doublechecked. Tobby72 (talk) 21:03, 10 June 2010 (UTC)

Question: why should we do the doublechecking? Why don't we just remove the contribs? If/when someone wants to have something restored, they can provide the proper sourcing. Woulnd't that be the proper way to take care of this? DVdm (talk) 21:02, 10 June 2010 (UTC)

Reply is on User talk:Tobby72#Misuse of sources. DVdm (talk) 22:07, 10 June 2010 (UTC)

Question: why take Tobby72's word that there are problems in this article? Most of the edits offered as problematic here appear to have few if any citations in them leaving me with the impression that this is a scatter shot campaign. While that doesn't mean there are other articles where there are problems I do not think it's effective to raise a red flag in every article with significant contributions by Jagged 85. From my perspective Tobby72 is not doing the project any favors with this approach. Jojalozzo 18:53, 18 June 2010 (UTC)

Lead sentence

The Encyclopedia of Astronomy defines the Universe as, “Everything we can detect, see, feel, know, or that has ever had any effect on our region of space. It encompasses all of SPACETIME, not just out to the visible horizon, and includes all particles, fields and interactions.”

The current statement is ok, but it seems to be changing rapidly because, ironically, there is not a universal definition of the Universe. Maybe we could use the ideas from the definition given above to formulate a better lead.

Andrew Colvin | Talk 00:22, 9 June 2010 (UTC)

At least it's not suffering from the "Your universe or mine?" problem (see my comment above). - DVdm (talk) 08:24, 9 June 2010 (UTC)

It does suffer from that - far more than what is presently in the lede - by being limited to what "we" (humans, I presume) can detect or observe. The ordinary meaning of "universe" includes even stuff we do not & perhaps never will observe (or know about). It also leaves us hanging about what "our region of space" means. It also might be taking the unusual view that future time is included - I say might because, while overly technical for a general purpose encyclopedia, "It encompasses all of SPACETIME' is also vague --JimWae (talk) 08:34, 9 June 2010 (UTC)

Hm, you stopped reading after the first sentence. The we-phrase is only part of the story. The remainder is covered by the phrase "It encompasses all of SPACETIME, not just...". The first sentence is the John-Doe part, to be completed by the second sentence, which is the technical part. Taken together, it looks perfect for the job. I think that is a viable solution of the problem that I mentioned earlier. DVdm (talk) 09:18, 9 June 2010 (UTC)

So what would be a good proposal for a better lead sentence? I see the point about the "we" part. That could be removed and changed to what we know, including what we do not know. However, is that really the universe? I presume that if we were not here to observe the universe, it would still be here. Help construct a better lead without the sociocentric or worldview of what “we” know. Andrew Colvin • Talk 01:27, 11 June 2010 (UTC)

What is really the universe doesn't really matter (NPI). We just have to decide which source we take and repeat what it says. We can take a dictionary or we can take an encyclopedia, but I would prefer a specialized enc. over a generic dict. We could say that the Encyclopedia of Astronomy defines the Universe as etc... just like the bolded statement. We can keep the we-part, since the non-we part is covered by the spacetime part. If we do that; we should replace "SPACETIME" with spacetime though. DVdm (talk) 10:07, 11 June 2010 (UTC)

There is another definition from the Encyclopedia of Astronomy and Astrophysics that reads as, “The sum of everything that exists and of which we can be aware; the entirety of space. There is a semantic difficulty in talking about the universe; on the one hand, we define it to be ‘everything’, but it may be (a) that our universe is finite, yet unbounded; (b) that the accessible universe is only a small part of a much larger entity, most of which we cannot observe; or (c) that there exist other universes of which we are not ‘aware’.”

I like the previous definition and I agree that the SPACETIME should be lowercased. I think it was caps by paste from the dictionary to tell you to look up Spacetime in the same book. Similar to a link here on Wikipedia. Maybe some of this new definition could be molded with the other one to form a stronger and more explanatory definition. Andrew Colvin • Talk 06:22, 12 June 2010 (UTC)

There's a problem in including "the entirety of space" in the universe. We cannot be sure if the author means "space" to be "3 dimensional space" or "outer space". If 3D space is intended, it makes it seem as if by adding "space" to the "contents" of the universe, we are listing some additional entity that is not already covered. The same problem applies to adding "spacetime". We have over 40 sources that do not include "space" or "time" or "spacetime", and only a very, very few that do. There is no need to include "spacetime" among the contents of the universe. What would be left out by not including it in the list? Perhaps something along the lines of "everything ever located anywhere within space". (The use of "ever" would thereby also include objects from times past.)--JimWae (talk) 06:51, 12 June 2010 (UTC)

This is harder than I thought it would be to define the Universe. Maybe we could take a different route still including much of the first definition I gave with the addition of something along the lines of, “the product of the big bang…”? Adding the big bang into the equation would allow for anything that we do not know of to be included in the universe. I perceive the universe to be just the place that we reside as a result of the big bang. Anything outside of the product of the big bang would have to be considered speculative or as described lower in the article, a multiverse. Thoughts? Andrew Colvin • Talk 21:38, 12 June 2010 (UTC)

I like the second Encyclopedia of Astronomy definition above. Remember that most readers will be nontechnical people who merely want an ordinary definition which they can understand. Rather than coming up with a long, complicated lead sentence that is overly inclusive and confuses people by covering all the esoteric possibilities, it states the most common definition and in the second sentence enumerates the more esoteric types of "universes" that aren't covered by the common definition. The existing lead para also takes this approach and I think is pretty good --Chetvorno^TALK 03:07, 14 June 2010 (UTC)

How is this for a definition?

The Universe is the sum of everything that exists and of which is the ample product of the big bang. The Universe comprises the totality of everything that exists visibly, and beyond the visible horizon. It includes all particles, fields, and interactions making up the structures observed today and in the past.

There is a semantic difficulty in defining the Universe. The word Universe is usually characterized as encompassing everything, however it may be (a) that our Universe is finite, yet unbounded; (b) that the accessible Universe is only a small part of a much larger entity, most of which we cannot observe; or (c) that there exist other Universes of which we are not aware.

I am not sure if Universe needs to be capitalized each time and I am not sure if the wording is clear enough. Suggestions and modifications welcome! Additionally, this would replace the first and half of the second paragraph in the lead. Andrew Colvin • Talk 03:31, 14 June 2010 (UTC)

My feeling is that the term "Big Bang" should not be included in the first sentence; the term "universe" was used before the Big Bang theory, and is not dependent on it; in addition nontechnical readers won't know what it is. I'm also kind of bothered by the emphasis on the term "visible" although I understand the importance of including the parts beyond the visible horizon. Just my two cents --Chetvorno^TALK 19:08, 14 June 2010 (UTC)

Dodecahedron Multiverse

This keeps being added to the article and often removed. Is it worthy to be part? Andrew Colvin • Talk 20:16, 13 June 2010 (UTC)

if you see my links that i have posted it has a lot of evidence that points out that the universe is a dodecahedron.THE WMAP probe sent by nasa was analyzed by a team of french cosmologist-topologist and it was found to be true. here more studies

http://en.wikipedia.org/wiki/Talk:Universe#no_mention_of_dodecahrdron_multiverse

his book: http://books.google.com/books?id=LLIGTaVATCYC&printsec=frontcover&dq=jean+pierre+luminet&cd=2#v=onepage&q&f=false manchurian candidate 05:57, 14 June 2010 (UTC)

I am, to a certain extent, sure that it is a possibility that the universes topology is dodecahedral and that is well worth mentioning, however that prospect must be taken with skepticism at the present moment. Reason being that just because of Jean-Pierre Luminet’s expertise on the subject does not mean that it is correct. Before assuming that he is correct ask yourself a few questions. Likely, Luminet is a credible author and scientist; however, does he have a consensus? Is the idea of a dodecahedron topology of the universe a widely accepted theory? Are their peer-reviewed papers and scientific journals on the subject?

Please present us with a bit more credible information about the subject and it may become more accepted for its inclusion in the article. I noticed that reading the back cover of the book you provided states, “…where possible topologies of the universe…” This I assume means that the dodecahedron universe is a possibility, not a fact or theory.

In no way is this help in any way hostile, it is just the reason for the removal of the material and the reason for exclusion. Andrew Colvin • Talk 07:23, 14 June 2010 (UTC)

there is again no proof of multiverse so why do we have many world hypothesis.the thoery of evolution is a theory but it widely used as evolution.the theory of a molten earth is a theory but it is widely said as moltern earth. i am not posting the dodecahedron multiverse as my or jean pierre idea.the NASA WMAP mission prooves it.i have given soo many links.if you care to read all the links which has all the raw scientic data which points to a finite dodecahedron universe then it should be mentioned.IF the NASA WMAP mission was never launched this theory would never exist. this topic should have a seperate page imo and in the mean time it should be a sub part of the multiverse.

also plz read this http://en.wikipedia.org/wiki/Poincar%C3%A9_dodecahedral_space#Poincar.C3.A9_homology_sphere In 2003, lack of structure on the largest scales (above 60 degrees) in the cosmic microwave background as observed for one year by the WMAP spacecraft led to the suggestion, by Jean-Pierre Luminet of the Observatoire de Paris and colleagues, that the shape of the Universe is a Poincaré sphere.[1][2] In 2008, astronomers found the best orientation on the sky for the model and confirmed some of the predictions of the model, using three years of observations by the WMAP spacecraft

the WMAP mission found this and this is proof that atleast we need to have this theory in this topic.

manchurian candidate 13:17, 14 June 2010 (UTC)

The possibility is interesting, but we are not here to publish exciting new results. To get this included at this level in this article, it is important that independent third-party sources take notice of this idea. That has not happened yet. It will now be removed. ScienceApologist (talk) 16:26, 14 June 2010 (UTC)

WHAT there is ample source of independent news sources.national geographic is one http://news.nationalgeographic.com/news/2003/10/1008_031008_finiteuniverse.html bbc http://news.bbc.co.uk/2/hi/science/nature/3175352.stm

"Astronomers from the US and France suggest that space itself is not big enough to support such waves.

A small, cosmologically speaking, finite Universe, however, made of curved pentagons joined together into a sphere, would fit the observations. "

now are you happy

let me ask you why is there a wiki page of a suns twin star nemesis http://en.wikipedia.org/wiki/Nemesis_%28star%29 when there has been not a single shred of evidence? scientists hypothesize that since earth goes through a extinction event every 26 mya so there must be a brown dwarf hidden in the oort clound. this dodecahedron model has been talked after WMAP probe was launched in 2001.it is via through the WMAP obervatory we known the about this model and and you dont want to add a iota of line?Also i have added the planck obervatory data.it is a improvement of the WMAP and the full structure of the multiverse would by known by its CMB by end of 2012.if you really want to remove it and remove nemseis star crap which has no proof manchurian candidate 16:55, 14 June 2010 (UTC)

I think we have made our points very clear Manchurian… Andrew Colvin • Talk 18:37, 14 June 2010 (UTC)

I agree. Wikipedia's NPOV states that an article must give "due weight" to "significant viewpoints" from reliable sources. "...articles should not give minority views as much or as detailed a description as more widely held views; generally, the views of tiny minorities should not be included at all" even if they are held by reliable sources. The dodecahedron proposal is one among many papers on the shape of the universe. It doesn't merit its own section. I removed it. --Chetvorno^TALK 18:41, 14 June 2010 (UTC)

great censorship at its best.i guess the nemesis article has more scientific proof than the dodecahedron model.at least add some 5-6 lines of this model in the multiverse article.why be so agasint this model?

why cant you have it named as a dodecahedron multiverse.why not reomve stupid article of nemesis.plz tell me why the nemesis articles needs to stay in wiki and not this. also for those who think its only third party.plz read this journal http://arxiv.org/ftp/physics/papers/0509/0509171.pdf

they have presented all the data in a scientific manner.I am a humanities student so i dont know didly squat.perhaps you can agree with thier inferences.

Perhaps there is some misunderstanding here. I, and probably others, have no objection to including the dodecahedron universe proposal in Wikipedia. It just doesn't belong in this article. Why don't you create a new article for it? Like the Nemesis (star) example you cite. That's where it belongs. It's just that if all of the hundreds of serious universe models that have been proposed were included in this article, it would be too long. --Chetvorno^TALK 18:41, 15 June 2010 (UTC)

the thing is that unlike other theories proposed by scientist like bubble multiverse etc this model has some scientific basis aka WMAP probe and the planck probe.we can have a separate page but i cannot do it.I dont know the command tools to create a page link it etc.but i really want this thoery to be mentioned in this page.by 2012 we will know for certain as the full details will be released.the prelim details will be released by dec 2010 and according to the url link i have posted above the scientists say the if the Q=>1.01 then the model would be proved. 59.95.131.16 (talk) 03:58, 16 June 2010 (UTC)

Manchurian:

1. first, I don't see any mention of a 'multiverse' in any of the links you provided. This seems, in fact, to be a model of a single universe with finite volume achieved by closure of opposing facets.
2. second, at present this is a model with interesting but weak supporting evidence. it does not even seem to be a major accepted theory, though it may be gaining credibility in the discipline. You seem to want to present it as a foregone conclusion, which over-emphasises its place in the scholarly discourse.

However, I think the solution to this problem may be to create a new section in this article called Shape of Universe which lists out the current and historical theories about the shape of the universe - including this one - along with supporting and refuting evidence. It would be a nice addition to the article regardless, and would help balance this addition so that it wasn't over-emphasized. do you think you could do some research and start fleshing out a section like that? --Ludwigs2 05:44, 16 June 2010 (UTC)

MC, I've read the arxiv paper you linked, and you are overlooking several important things:

• This is an arxiv paper. That means it has not been published in peer-reviewed literature of the type required by the WP:RS policy. This is a preprint - an early draft of a paper that the author hopes will get accepted by a prestigious journal, but has not yet been accepted to any such.

• The author's assumption that the universe has positive curvature is from the "1.02 +/- 0.02" figure he cites. The "+/- 0.02" figure is for one standard deviation. The expected value of omega is almost exactly 1 (indicating a nearly-flat universe), per the flatness problem. Most cosmologists interpret the WMAP data as confirming that the universe is very nearly flat. To confirm otherwise, you'd need to be several standard deviations away from 1, to have confidence that you aren't just seeing statistical fluctuations. A distance of between 4 and 6 standard deviations is considered "statistically relevant", depending on what you're trying to measure (detecting new particles usually requires being 6 sigma away from your noise).

• The author computes matchings for dodecahedral, octahedral, and tetrahedral spaces. All of these will produce some statistical matching of facets due to random chance. The author has to demonstrate that the matches are good enough that this is extremely unlikely to happen by chance. He hasn't done this. The range of curvature values his own models predict are 1.009, 1.015, 1.025; these are within one sigma of the WMAP data, but so is the 1.000 assumed by most cosmologists. He claims a Polish team's matching circle analysis gives 1.010 +/1 0.001, but he doesn't show any of his work deriving this number. He certainly didn't find that level of confidence from the WMAP data.

Long story short, the author's "careful analysis of the power spectrum" ends up seeing patterns where there probably aren't any. It's still an interesting idea to study, but so far the most plausible interpretation of the WMAP data is that it confirms flatness. You're going to need a much, much stronger case for non-flatness and for power spectrum oddities before anyone calls it "proof" of any given finite topology for the universe.

What you can say from this and other papers is that cosmologists have studied the idea that the universe has finite size, and have looked for the imprint of this in the microwave background. Nobody's turned up strong evidence for it, though. --Christopher Thomas (talk) 06:14, 16 June 2010 (UTC)

I will try to find out the polish team data on the internet.his articles have his email address.maybe you all can email him and ask him about other socentist confirming this thoery so we can better create the articel. All i know that the poincare dodecahedron is mentioned in the dodecahedron page,the jean pierre luminet page and the comsmology homology page.I have already written in the article that it needs to be verified and planck probe will give us prelim data in dec 2010 so i guess by 2011 we would know more and by dec 2012 all the data would be available.imo this article atleast warrants to have a topic in the main universe article.we can shorten the article but it is imporatant. manchurian candidate 11:34, 16 June 2010 (UTC)

I think this section clearly belongs in Shape of the Universe, not here. By the way, Manchurian candidate, you can sign your posts by typing 4 tildes (~~~~) after them. --Chetvorno^TALK 15:54, 16 June 2010 (UTC)

Yes, per WP:SUMMARYSTYLE, we can wax lyrical about topology theories in Shape of the Universe, but in this article we need to summarise that article's content, not repeat it all. This is a new and little recognised theory so it does not deserve placement in this main article. Fences&Windows 16:45, 16 June 2010 (UTC)

Ah, I had no idea that we had a separate article on the shape of the universe. there you go.

@ Manchurian: please talk a look at wp:cheatsheet which will give you tools you can use for editing articles and talk pages effectively. --Ludwigs2 17:20, 16 June 2010 (UTC)

why did you remove the pic and the word dodecahedron mltiverse.atleast bring those back. 59.95.130.218 (talk) 06:16, 18 June 2010 (UTC)

the shape of the unvirse is a total irony.there is no mention of the dodecahedron model.

i am adding this line and it is getting removed by a ego Hungary person. add tthe data gathered from jean pierre luminet about universe being a finite and shaped like a dodecahedron . manchurian candidate 17:10, 18 June 2010 (UTC)

Please do not treat Wikipedia as a game to make a WP:POINT. Try to establish talk page consensus before you add this or similar content to this article. DVdm (talk) 18:03, 18 June 2010 (UTC)

The term "dodecahedron multiverse" does not appear in the paper you cite. Using the word "multiverse" seems to be your own idea. That sort of thing is forbidden by the WP:NOR policy.

The purpose of Wikipedia is to summarize the views of well-established, well-accepted sources of information, not to publish new or cutting-edge information. In the context of science articles, the relevant policies are WP:RS, WP:UNDUE, and WP:FRINGE. The idea that the shape of the universe might be measured is noteworthy and has been widely published -- and is already mentioned in the article. Your favourite authour's idea about what that shape ends up being, on the other hand, has not yet been published in peer-reviewed journals and is not accepted as being any better than the many other proposals in that regard. As such, it doesn't merit a mention in the Universe article, and at best merits a very short mention (along with the other options proposed with similar confidence by their proponents) in the shape of the Universe article, and possibly a paragraph at the page about the paper's authour.

If you continue to re-insert this material against the advice of all of the other editors on this page, after all of the policies have been explained to you, then what you're doing is called "edit warring". Per the WP:EW policy, it'll get you blocked if you continue doing it. You seem to want to contribute constructively, so please restrain yourself to contributing within Wikipedia's rules. There are places where you can push cutting-edge proposals more strongly; Wikipedia isn't one of them. --Christopher Thomas (talk) 19:03, 18 June 2010 (UTC)

Article's first two paragraphs contradict one another

The first paragraph states that the universe is everything that exists.

The second talks about the possibility of other universes.

This is patently a contradiction. I suggest that the original definition should be brought into line with the modern definitions given below, which emphasise that a universe is everything within 'your' spacetime which is in some sense causally bound to everything else in this universe. This allows for a multiverse comprising of individual, 'disconnected' universes, as the second paragraph talks about. —Preceding unsigned comment added by 86.140.67.71 (talk) 15:13, 21 June 2010 (UTC)

Your proposed definition wouldn't cover one of the main "multiverse" models, the bubble universe theory, which consists of multiple non-causally connected universes. The existing definition isn't a contradiction. Keep in mind that most readers of this page are nontechnical people merely looking for the most common, understandable definition. Many esoteric universe models have been proposed. Rather than coming up with a long, confusing, overinclusive first sentence that covers all the exotic possibilities, the existing intro gives a definition that covers the most common meanings of the term "universe", and in the second sentence mentions the more exotic models not covered in the first sentence. I think this is a much better approach for a general-use encyclopedia article. --Chetvorno^TALK 17:40, 21 June 2010 (UTC)

I don't think it's particularly technical. If somebody is reading this article, they are certainly going to be interested in the idea that there may be other universes, and hence the universe is very far from 'everything that exists'.

At the very least this article shouldn't contradict itself; that will only confuse people who read it.

"The Universe comprises the totality of everything that exists"

and

"some cosmologists have speculated that the "Universe" we know of is just one of many disconnected "universes""

are patently not compatible statements.

I think I will edit the article very slightly so that it at least points out that these definitions are not compatible with each other, which would be better than the present state in which the contradiction is treated as if it isn't there. —Preceding unsigned comment added by 86.140.67.71 (talk) 15:08, 24 June 2010 (UTC)

• The commonest present def is that the "universe" is "everything that exists...". Some people have speculated that there might be things that exist that we can never access, nor observe, nor ever know about in any way. Some who engage in such speculation refer to these other speculative "worlds" as other "universes", some call each other word a "multiverse", & some use "multiverse" for the collective "everything". (i.e. Not even every such speculator agrees that the term "universe" could not still be applied to "everything..." in this context.) There will always be speculation that perhaps there is something more that can (or, more weakly, "has") never be/been observed nor known about. The existence of some such other worlds (by definition) will always remain speculation. There may come a time when we observe a "world" so separate from ours that we may wish to give it a separate name. A decision then about how to continue to use the word "universe" might be a real choice that is eventually made. There will still be a sense in which some word (and that word could continue to be "universe") is used to refer to everything that exists. For now, it is quite appropriate to say that in current actual usage, "universe" signifies everything. Those who speculate about other inaccessible "worlds" may sometimes use the word "universe" in a more limited sense to make a point - but not even all of those agree on how to use the word. Some have proposed a more limited meaning for "universe" based on speculation that there are other "worlds" extremely inaccessible from our "world" (i.e. more extremely inaccessible than the presently accepted "edge" of "our" universe). Many words do not have a unique meaning - especially not when language is being stretched to make a point about speculative ideas. --JimWae (talk) 19:14, 24 June 2010 (UTC)

I'll agree that there is a real problem here. It is not so much that the paragraphs contradict each other as they are just not clear and not well supported. My suggestion is to introduce the concept of the "observeable universe" as distinct from the universe as "everything that exists." This way we can introduce theories about what the universe might have looked like prior to the big bang and explain that such states are beyond the "observeable universe" but but may well be part of the broader universe. Let's face it, modern cosmological theory is full of notions of big bangs as commonplace in the "big universe" and that we are simply stuck within a single "observeable universe" beyond which we can only theorize. If these theories are correct these other places are no less real, no less existant, and therefore part of "everything that exists". Thus ideas of multiverse models can be introduced in a clearer way. The "universe" is everything that exists - even that which we cannot observe. The "observeable universe" is everything that we have the potential to observe and that is covered by current theories of big bang, inflation and so on. —Preceding unsigned comment added by 151.191.175.204 (talk) 14:09, 29 June 2010 (UTC)

I think we need to be guided by actual usage of the term. The first sentence adequately covers everyday usage, as "everything that exists". The succeeding sentences need to cover usage in cosmology, where it differs from "everything that exists". Although in cosmology "other universes" always refer to regions unobservable in principle and undetectable from ours, not all unobservable regions are called separate universes. In the Big Bang model, the parts beyond the speed-of-light horizon, outside the observable universe, are still considered as part of our "universe", so this conforms to the everyday usage. However in bubble universe theories, a very active area, the non causally-connected bubbles are usually described as multiple "universes". Another alternate usage is in oscillating universe theories, where the (unobservable) consecutive iterations between successive "crunches" are often described as separate "universes". I think we should avoid generalizations and just describe how the word is used. --Chetvorno^TALK 01:24, 30 June 2010 (UTC)

Pie Chart

I added up the numbers on the pie chart in the article, and the sum of the numbers was only 99.83%. So what, is the other .17% black holes, the absence of anything at all? Could somebody try to fix this? Pawsrent (talk) 21:44, 30 June 2010 (UTC)