Talk:Universe

Totality of existence

There is a difference between universe as totality of existence and other terms mentioned (cosmos, world, nature, ...), and it could be that this difference is enormous considering various philosophical, religious and even pyhsical (multiverse) theories about existence. — Preceding unsigned comment added by 93.103.74.8 (talk) 17:21, 22 December 2013 (UTC)

For this article, Physics/Astronomy/Quantum Physics "own" the article name plus the article multiverse. Other definitions may be construed but would need to be qualified. Universe (religion) or Universe (philosophy), that sort of thing. There is no ambiguity here, nor room for further disciplines. Student7 (talk) 18:50, 26 December 2013 (UTC)

If so, then the first 'phylosophical' statement in the article doesn't belong here. — Preceding unsigned comment added by 93.103.74.8 (talk) 20:44, 1 January 2014 (UTC)

The first sentence of this article presupposes naturalism, making it a philosophical statement. This is why I find it difficult to take Wikipedia seriously at times. It's obvious that the sentence was construed this way to push an agenda. Science is a methodology by which we can observe, study, and predict physical phenomena (e.g. planets, stars, etc.). Therefore, one would have to presume there is nothing but physical reality in order to state that the universe (a physical manifold) is the totality of all existence. 24.128.244.108 (talk) 03:13, 10 March 2014 (UTC)

Then your problem is not with Wikipedia but with encyclopedias in general, because virtually all encyclopedias define it that way.

If your claim is true, then I suppose I would take issue with those other encyclopedias as well. They would be just as misleading and biased with their definition of universe. Is your claim true though? Even if it were, that's not a good argument to continue the ignorance. Is it? In any case, I noticed you didn't touch upon the main point I was driving at with my comments. That being said, according to http://www.britannica.com/EBchecked/topic/139365/universe the universe is "the whole cosmic system of matter and energy of which Earth, and therefore the human race, is a part." A much better first sentence for the definition of universe, I must say. Notice how the definition doesn't presuppose naturalism in the opening sentence. 24.128.244.108 (talk) 04:42, 10 March 2014 (UTC)

This is exactly what I came here to post. I think that adding the qualifier "The Universe is commonly defined as the totality of physical existence" would solve most of these philosophical problems with that opening sentence. Wikipedia is a document of the human experience of life, and I think it's inappropriate to completely ignore the metaphysical/spiritual realm of existence that an overwhelming majority of human beings believe in -- whether you may agree or disagree. Pinkpills (talk) 08:33, 29 May 2014 (UTC)

Inserting religious dogma in this article is no more appropriate than going around and inserting, "but science says this is stupid" in every article on religious topics. — Gopher65_talk 13:42, 29 May 2014 (UTC)

Totally agree with Gopher65's comments above. This article is no place for religious dogma. David J Johnson (talk) 13:59, 29 May 2014 (UTC)

You two are the first that have brought up religion. As far as I can see the change made had nothing to do with religion, but more with logic and philosophy. To highlight the problem with the old first sentence consider the following: Mathematics exists. But is mathematics part of the universe as commonly defined? Probably not. Adding the word "physical" to the first sentence nicely clarifies in what sense the word "exist" is used.TR 16:44, 29 May 2014 (UTC)

Then may I respectfully suggest that you re-read Pinkpill's comments above, which is furthering the religious theme - as is the rest of their contributions to Wikipedia. David J Johnson (talk) 16:59, 29 May 2014 (UTC)

My I respectfully ask that you actually respond to arguments? Whatever his motivation, his change was an improvement for the reason I mentioned above.TR 20:14, 29 May 2014 (UTC)

I have responded to the "arguments", you are the only editor who thinks that Pinkpills changes are an improvement. Further you have no reason to engage in a personal attack in your comments when you make an edit. You need to abide by Wikipedia conventions in future. Unlike yourself, I have no intention of entering a edit war with you. I'm happy to wait for other editors response to the matter. As far as I'm concerned - case closed. David J Johnson (talk) 20:43, 29 May 2014 (UTC)

I agree with Gopher65 and David J Johnson; the qualification "physical" is not needed. --Chetvorno^TALK 20:58, 29 May 2014 (UTC)

Although not strictly necessary, it does help to provide context for the definition. As I noted above, the current first sentence can be construed to include abstractions (like mathematics) that would not normally be considered "part of the universe". In this sense having the qualification "physical" is somewhat helpful. I have yet to see anybody here provide an argument why have that qualification would detract from the article.TR 21:14, 29 May 2014 (UTC)

I recently read a bit about this, and, fascinatingly, it isn't known whether math exists as a construct within our universe, or if it exists independently of our universe in a greater multi/metaverse, or if it exists independently of any universe, as a kind of sea of probability. It's an interesting subject:). But because it isn't known (or even "leaned" either way, as far as I can tell), we can't really make a claim like that in the opening sentence. — Gopher65_talk 00:42, 30 May 2014 (UTC)

It's not a claim about physicalism, MUH, etc., it helps distinguish the topic of this article from Universe of discourse, for example.—Machine Elf ¹⁷³⁵ 02:50, 30 May 2014 (UTC)

The first sentence is extremely bad but adding "physical" to it makes it worse. Where is the reference for this? Bhny (talk) 04:08, 30 May 2014 (UTC)

Why ask for a reference for something supposedly "redundant"? It's not btw, but what people seem troubled about is that it's too specific in the sense given at the "physical universe" article: that it would exclude the supernatural. However, that seems ok to me because this article doesn't actually cover the supernatural, fictional universes, mathematical universe (mathematics), etc.—Machine Elf ¹⁷³⁵ 06:16, 30 May 2014 (UTC)

It is frustating to try to discuss, when people do not explain why they think something is "redundant" or "makes things worse". It makes building consensus hard.TR 08:00, 30 May 2014 (UTC)

"Physical" is redundant because the universe is everything that exists and non-physical things don't exist. Saying "physical" also weirdly implies the existence of non-physical things outside of the universe. But that is only my opinion and doesn't matter! If the references say "physical" then we use physical. "Why ask for a reference" seems a crazy question to me. Bhny (talk) 19:30, 30 May 2014 (UTC)

Perhaps redundant given the "Physical cosmology" sidebar, but I agree the "commonly defined" part's pure weasel.—Machine Elf ¹⁷³⁵ 05:15, 31 May 2014 (UTC)

"Saying "physical" also weirdly implies the existence of non-physical things outside of the universe." — That is exactly my problem with that phrasing. It's nonsensical. — Gopher65_talk 12:24, 31 May 2014 (UTC)

I like this debate I got going here. I still stand by my wording. "Saying 'physical' also weirdly implies the existence of non-physical things outside of the universe." Not exactly, but close: it implies the possible existence of non-physical things outside the universe. This is where the question of neutral POV comes in. To a naturalist, the physical universe is all there is, end of story. But neutral does not mean "naturalist". The definition should be fair to the very large majority of people who believe in "higher" realms of whatever kind. That isn't nonsensical at all; it's simply a different opinion than yours. So I still think we need to be careful how we define the Universe, and calling it the totality of physical existence works for most beliefs. But maybe there is an even better way to word it.Pinkpills (talk) 12:37, 31 May 2014 (UTC)

The reason it is nonsensical is because - by definition - the universe contains everything physical and non-physical that can impact our existence. The only reason to insert the word "physical" there is as a weasel word to try and imply that there are non-physical things that exist inside the universe, but also non-physical things that exist outside the universe. You've now entered the realm of wide imagination. This addition is necessary only if your personal beliefs include things that are so far outside the known laws of physics that no reasonable addition to those laws could cover your beliefs. What's ruled impossible by that line of reasoning? Not much. FTL? Nope, we can imagine laws that would cover that. Might not be true, but it could be. "Higher planes of existence"? Might exist. May well not, but meh. "Aliens killed my cattle!"? They're almost certainly not here, but they aren't precluded from existing or being here. Telepathy? Doesn't seem likely, but we can certainly imagine that new physical laws could be uncovered that would allow previously unthought of types of long distance communication. Miracles/curses? Well, maybe something exists that alters the laws of probablity somehow? Doesn't seem likely, but maybe. That covers almost every belief system, and it's all included inside the word "universe". What's precluded though? As I said, not much. Some older mythologies can no longer exist (hollow Earth, glass spheres, etc). But for modern mythologies? Pretty much just one: an all seeing, all power, all knowing, omnipresent God. That is precluded. That is impossible. That cannot exist within our universe.

So, as I originally stated waaaay up at the top of this topic, putting the word "physical" in there is inserting religious dogma into this article. And not even general religious dogma, but rather support for a specific subset of Abrahamic religions. This is not a religious article. It is not the place for mythology. There are articles that are all about such topics. That is where statements like that should go. — Gopher65_talk 14:38, 31 May 2014 (UTC)

I have to go to work now, so no edits for a while, but I hope that didn't sound overly harsh. It was intended to get an idea across, not be mean. — Gopher65_talk 14:42, 31 May 2014 (UTC)

Edit Warring

Well, with the exception of obvious vandalism I don't engage in more than 1 revert of someone's content. I don't like edit warring. So hopefully we have enough people chime in on this that a consensus is possible. — Gopher65_talk 03:45, 30 May 2014 (UTC)

"commonly defined" weasel words

I've tried unsuccessfully before to remove the weasel words "commonly defined" from the first sentence. I think our current definition is good but far from a common one, and it is now a lie to say "commonly defined". Also it is weasely and against WP:REFERS. The standard structure of the first sentence of a good article is usually <topic> is <definition>. If there are two or more definitions then we should just list them or find a simple definition that covers them all. As it is now we are just inferring that there are other better, less common, definitions that we won't tell you about. Bhny (talk) 04:19, 31 May 2014 (UTC)

Universe and reality

The universe is certainly part of reality--but is it the totality of reality? The opening paragraph of this article seems to indicate that it is. In particular, I'm talking about the sentence, "Similar terms include the cosmos, the world, reality, and nature." First, I find this sentence redundant because universe was already clearly defined before it. It's redundant as far as that's concerned unless the editor is making an attempt to lump "universe" in with "reality," as though the universe and reality were synonymous. Perhaps they are and perhaps they aren't. The terms are certainly synonymous to the naturalist, but that isn't a neutral position. 24.128.244.108 (talk) 06:05, 6 June 2014 (UTC)

It doesn't say the "universe" is synonymous with "reality", Different terms have been used in history and in everyday discourse to discuss the concept we now call the "universe" For example the word "World" was used extensively in Western philosophy to mean "universe" (particularly before it was understood there were other "worlds"). Some of the terms from the sentence are also used in dictionary definitions of "universe". We've had a lot of discussion on this page already about the philosophical meaning of "universe". I think it's fine the way it is. --Chetvorno^TALK 08:33, 6 June 2014 (UTC)

The opening paragraph defines the universe as a physical manifold which is true; that's what it is. However, at the end of the paragraph a laundry list of words are used and we're told that these are all similar to what the universe--a physical manifold--is. One word in the list is "reality." But reality encompasses absolutely everything that is real or actual, which would include even the supernatural (e.g., God). The problem with this is the supernatural is by definition a category of being that transcends the universe or nature. So there's a glaring problem here unless one holds the belief that there is no such thing as a category of being outside of nature, that naturalism is true, that the universe IS reality, and not merely a stratum of reality. 24.128.244.108 (talk) 09:07, 6 June 2014 (UTC)

And that is why it says "similar" and not "equivalent", i.e. there is overlap in how the terms are used, and within a certain POVs (but not others) they could even be used as synonyms.TR 09:19, 6 June 2014 (UTC)

Similar how though? Reality encompasses everything that is real or actual. The universe encompasses all physicality. So in what way is "reality" and "universe" similar? Calling these two words similar is like calling the set of natural numbers and the set {1, 2, 3} similar. I guess they're similar in the sense that they're both sets, but that's not worth noting. I don't think these two words are similar in any way or to be more modest: in any meaningful way. For the sake of my next point, let's say they're similar. How similar are they? That isn't explained at all, which makes things confusing and ambiguous for the reader. There are people reading the opening paragraph, being taught that the universe is spacetime or all physicality, and then they go on to read that this is similar to reality. But when one investigates this claim by clicking on reality they find that reality is much bigger than the universe--or at least there is the possibility that it is.

There seems to be something fishy going on here. One problem is many of the editors here at Wikipedia don't have any formal training in the topics that they're editors for--so one see them doing silly things like comparing "reality" with "the universe." A person with a little training in science and philosophy wouldn't make such a mistake in a so-called encyclopedia that is supposedly neutral, unless they were purposely trying to push a certain viewpoint like naturalism. 24.128.244.108 (talk) 09:42, 6 June 2014 (UTC)

A wrong use of "infinite"

This article states "The size of the Universe is unknown; it may be infinite." Yet it also states " Observations of supernovae have shown that the Universe is expanding at an accelerating rate." Now I'm no Einstein but I know that if the Universe had a beginning in the big bang and we are now 13.8 billion years in, It must be really big, but by definition cannot be infinite, because infinity is defined as "without limit". Please this is really simple and I was thinking about how it didn't make sense after reading. It can't be infinite regardless of how quickly it has been expanding for 14 billion years.

What is actually happening is a non-terminating process, space is continually growing larger, Yet it's not infinite because each individual light year, or mile, or foot, or inch etc. is finite and is achieved in a finite number of steps or time. Rather, the expansion of the universe "Approaches infinity". Yet, it cannot currently be infinite, not even in speculation (according to the previous mentioned facts of this article).

In fact, nothing in our universe can currently be infinite because time itself had a beginning in the big bang and terminates up to this very moment. For some physical property of our universe to have "no limit" and have a beginning at some point... time itself would have to stop completely - Only then will you never reach an end. The absence of time is true infinity.

Infinity is an abstract concept that cannot be observed in nature. Thanks. I hope this gets cleared up.

ps: This applies to the observable and unobservable universe. Carb0nshell (talk) 06:32, 30 August 2014 (UTC)

That isn't presently known. Available evidence gently *suggests* that the universe is spacial finite (maybe, or maybe just our local bubble is spatially finite...could go either way), but it doesn't say much about whether or not it is temporarily finite or infinite. Remember, something only has to be infinite in one direction (ie eg, a number life from 0 to infinity) to be infinite. So even if the universe could be said to have had a conventional beginning - a singularity popped into existence and instantly expanded - and it could still be just like that number line. It could have had a set beginning, go on forever, and be infinite in the direction of the future. And in that case it would be infinite, just like that number line. — Gopher65_talk 12:35, 30 August 2014 (UTC)

I think you [(Carb0nshell)] are mistakenly thinking of the universe as a simple expanding sphere. Read this: Shape_of_the_universe- "According to cosmologists, ... the shape of the universe is infinite and flat, but the data are also consistent with other possible shapes". Bhny (talk) 13:27, 30 August 2014 (UTC)

A spatially infinite universe does not necessarily follow from the non-detection of curvature in the local universe. The article you link to actually talks about that a bit. Basically, if we detect the local universe to be "flat", that tells us nearly nothing about the shape or size of the universe. It's only if we detect curvatures that we can really start to speculate. This is (among other reasons) because any shape universe will appear flat if it is much larger than our local observable universe. All we can really say from our current measurements is exactly what this article says: "The size of the Universe is unknown; it may be infinite." That is literally the entirety of our (relatively certain) knowledge in this area. — Gopher65_talk 15:40, 30 August 2014 (UTC)

Sorry by "you" I meant Carb0nshell, who may be using a balloon metaphor for the expanding universe. Bhny (talk) 19:25, 30 August 2014 (UTC)

The universe has been expanding for billions of years. We could mentally freeze this current moment in time and measure all of the finite miles back to the center. If we did this, we would get a concrete number, not infinity.

Also, remember: The future hasn't yet happened. Our timeline terminates, or ends, or stops at the most recent moment of present time. (its constantly being pushed froward, as time moves on). Infinite would mean the future already existing. Otherwise we only "approach" infinity with each passing second. Of course time is not infinite in the past direction - having an origin with the Big bang. So time has a beginning, and an end - that's constantly moving closer to infinity - yet it isn't infinite because it isn't complete. The number line is a good example of a complete infinity. Time - unlike the number line - is moving. Carb0nshell (talk) 09:25, 31 August 2014 (UTC)

Shape shouldn't matter here if the universe is somehow changing in any way through time. shape-wise, or really in any respect, then it can't be infinite. Carb0nshell (talk) 09:35, 31 August 2014 (UTC)

Carb, if you wouldn't mind, please put your comments at the bottom of all the other ones. It just makes it easier to follow the flow of conversation:).

As to your comment, I want you to ignore the universe for a moment, and we'll talk about infinities in general, since you seem to misunderstand the term.

Imagine this: you have an infinite set of numbers. This set, in fact: {0, 1, 2, 3, 4, 5... ---->}. This is the set of natural numbers. It starts at 0 and just keeps going forever. So it's an infinite set. Ok so far? Everyone has trouble with infinity. It's a weird concept.

Ok, so we have this infinite number set. You take out a single number, let's say "13", and you say, "ah hah! 13 is not an infinity! Therefore this isn't an infinite set of numbers!" ...Well 13 certainly isn't infinite, but that isn't the point. You can always extract a single number, or in fact any finite set like {13, 14, 15}, say, and that finite set will, of course, be finite. It will be finite because you specifically defined it as finite when you extracted it:). But just because you can pull out individual non-infinite numbers from that infinite set, that doesn't have any bearing on the set itself. The set of natural numbers is still infinite. It still goes on forever. For our purposes here, infinite basically means "goes on forever in at least one direction". In the case of the set of natural numbers, it has a definite beginning (either 0 or 1, depending on which you choose to start with), but it doesn't have an ending. It is only infinite in one direction.

So what does this have to do with the universe? Well, you said (paraphrased), "ah hah! The universe is 13 billion years old! That means it isn't infinite!" Well... no. That just means that you pulled out one number of an infinite set. Of course that particular number (that particular age) isn't infinity large, but it couldn't be. That's just not how infinities work. — Gopher65_talk 15:23, 31 August 2014 (UTC)

You are also questioning the size of the spacial dimensions of the universe, claiming that it can't be infinite, because it started a finite time in the past. This is not the case. A universe could *poof* into existence and be infinitely large, or it could *poof* into existence and be a finite size. Universes are weird things. They don't follow the same rules as you and me, or as a balloon that you're blowing up.

I know scientists will say, "the universe expands like a balloon filling with air", but that's just an analogy. A really, really bad analogy, which gives people a lot of wrongheaded ideas about the universe.

I also think you're making the (very common) mistake of thinking of the Big Bang as an explosion which blew 'stuff' outward. If you make that assumption, then it totally makes sense that the universe would *have* to be finite, right? Because the explosion has been going on for 13.8 billion years, and no matter how fast the stuff is exploding outward, it is still finite in size.

But that's another really, really, really inaccurate analogy. That one isn't so much inaccurate as it is flat out wrong. The Big Bang didn't explode. And from the inside, even expansion is hard to see. Oh it "expanded", but an infinite object can still expand (see, infinities are weird, aren't they), either locally or as a whole. Just think about some points on our number line from the comment above: {12, 13, 14}. {40, 41, 42, 43}. {60, 61, 62, 63}. {1000000, 1000001, 1000002}. Each individual point on the number line, both present and future, is growing larger. But the number line as a whole is infinite. Weird, right? That's not an exact analogy either, but I don't think there are any exact analogies for the universe;).

I'm not sure I can properly explain to you exactly why the universe might be infinite (it's complicated), but I hope I've been successful in helping you see some of the flaws in your logic. — Gopher65_talk 15:38, 31 August 2014 (UTC)

I have one last comment about how freaking weird the concept of infinity is. Imagine the set of natural numbers again. We'll use the version without 0 this time, for simplicities sake. {1, 2, 3, 4, 5, 6... ---->}. Now, imagine a second number line where we count by twos instead of by ones. {2, 4, 6, 8, 10, 12... ---->}. Both sets go to infinity. They're both infinite. But the second set, the one that counts by twos, is twice as large as the first set. No really, the second infinity is (provably) 2x the size of the first infinity. This isn't a trick. It really is. You see, infinities are never ending, but that doesn't mean they're all the same. Some infinities are... bigger... I guess, than others. We don't really have words to describe that. Bigger doesn't really work there, does it? But that's the way it works. One last time: infinities are weird;). — Gopher65_talk 15:45, 31 August 2014 (UTC)

Our arguments all boil down to the structure of time. If the future is some construct that already exists out there, just waiting for us to arrive at its pre-built location, then your logic could work. I don't think most people see time as pulling random numbers off of an infinite number line, but rather as the inevitable progression into the future with the passing of present events into the past. Maybe, however, we do need to give science more time before changing this article. Pun intended.— Carb0nshell (talk) 19:40, 1 September 2014 (UTC)

Recent addition to introduction on multiverses

There seems to be an incipient edit war over the addition of a paragraph to the introduction saying that the terms "multiverse" or "many universes" are unscientific. --Chetvorno^TALK 04:51, 1 September 2014 (UTC)

My feeling is, first, regardless of the validity of this point of view, it contradicts the sourced sentence at the end of the introduction mentioning multiverses, as well as the sourced section Universe#Multiverse theory. To add this paragraph, it needs to be sourced, and the sections of the article on multiverses should be deleted for consistency. Second, the paragraph strays into an off-topic rant on neologisms, which should be deleted. Third, the issue of whether the "multiverse" hypothesis should be included in this article is controversial and has been argued ad infinitum on this Talk page before; it should be discussed on this page before changes are made to the article. --Chetvorno^TALK 04:51, 1 September 2014 (UTC)

I agree with with all your points, in fact I think it's quite over the top, thank you.—Machine Elf ¹⁷³⁵ 19:58, 1 September 2014 (UTC)

I have never understood why, if universe is defined as everything, "multiverse" isn't an oxymoron. 97.64.209.102 (talk) 21:04, 10 October 2014 (UTC)

Not infinite

I have researched the universe a topic and in my research it say that the universe is expanding so therefore it can not be defined as infinite.

Fun facts. The universe as far as we know has no edge an is not expanding from a singular point in space.

If I am wrong about any of there things I am talking about I would like to know what and why it is wrong. — Preceding unsigned comment added by ZeroKool00 (talk • contribs) 09:06, 27 September 2014 (UTC)

This was just discussed in the section two sections up from this one (and many, many times before this). Long story short, we don't even know what shape the universe is (current evidence points toward a "saddle" shaped, or infinite universe). Until we know the shape of the universe, we can't tell if it is spatially finite or infinite. Also, the universe may be temporarily infinite in one direction (the future). — Gopher65_talk 12:48, 27 September 2014 (UTC)

I agree. In addition, ZeroKool00, a spacially infinite universe can still be expanding. Expansion just means the distance between any two sufficiently separate objects, such as clusters of galaxies, is increasing. --Chetvorno^TALK 15:09, 27 September 2014 (UTC)