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1. I am extremely sorry that I kept messing up the equation 10^40 plus 1.7x 10^106. I finally understand that the correct value is 1.7 followed by 65 zeros and then a one x 10^106, a very insignificant number so I also agree that it should just be kept at 1.7x 10^106. I apologize again for the erroneous corrections I have about this subject matter. I began to understand it using large numbers. I understood that 10^106 is 10^66 times larger than 10^40 thus 10^40 only represented 0.followed by 65 zeros and 1. I understand my error, so I thank you for enlightening me but there is still one thing I do not understand. You say that “So, 3^3^3 is the same as 3^(3^3), and is not the same as (3^3)^3 = 3^9.” This is not true 3^3^3 equals 19683 and 3^(3^3) equals 7.62 x 10^12. Obviously the latter number is much larger. Just type it in a graphing calculator and you can see for yourself.
2. The Poncence Recurrence time was messed up so I changed it according to the offical sources. You can see for yourself.
3. The Black Hole Lifetimes should be kept there because it is relavent to the article since different black holes evaporate at different times. You yourself Spacepotatoe have agreed upon this table since you were the one who created it.
4. The lifetime of 1.7x 10^106 years for 20 trillon solar mass black holes, was a number that Spacepotatoe said he found in a reliable source. I had originally but 10^106 years as the lifetime of 20 trillion solar mass black holes but you, Spacepotatoe said that the correct number was 1.7x 10^106 according to your source which you said was much more reliable then mine, so I accepted your word. But now Ashill says there is no source for this and that 1.7x 10^106 is to accruate to be known. I wrote 10^106 years in the first place but Spacepotatoe said he had found a source much more reliable then this so I went with this word. So this 20 trillion solar mass black hole lifetime has been sourced by me and then resourced with Spacepotatoes “much more accurate” source. Ironic how Ashill now says 1.7 x 10^106 is too accurate when I put 10^106 all along and Spacepotatoe comes along and repeatedly changes it to 1.7 x 10^106 years because he says it is much more accurate then my source. So finally I just took Spacepotatoes word, but now Ashill doesn’t like it and says its not relevant and not sourced when it is in fact both relevant and sourced even reliably sourced by Spacepotatoe. Understand that most of the information in this article is from Spacepotatoes sources so I am not supplying these reliable sources.
5. I still don’t understand why I can’t add stars are flung from their orbits in 10^18 years. It is sourced so why can’t I put that in addition your new section about Galaxy Evaporation since stars being flung from their orbits in a prerequistie to Galaxy Evaporation? Could you please tell me?
6. Why are all of things that we agreed on now being changed and if the Coalasing of the Local Group does not relate to the topic then why would Spacepotatoe add it? Please let me know for this article is getting out of control and I need some answers as to why things are being changed so much such as Black Hole Lifetime table after it had been agreed upon for so many weeks and there has been consensus on it, and now all of the sudden Ashill wants it gone. And anyway it was Spacepotatoes idea for the Table so why would he add the table if it wasn’t relevant to the article? I just need some answers? Sorry for all the questions. Thank You for you cooperation. Thank You Maldek ( talk) 01:44, 17 July 2008 (UTC)
Spelling of name of User:Spacepotato | |
Spacepotato | Spacepotatoe |
OK. Good. Right. Ça va pas mal. ¡Muy bien! |
Not OK. Bad. Wrong. Tout est perdu. Estamos en el quinto coño. |
[I transferred this question to Talk:Future of an expanding universe because although that article's content is a large portion of this one, the "heat death" scenario with maximal entropy is inconsistent with speculations about planets made out of neutrinos ;)] Wnt ( talk) 17:19, 18 July 2008 (UTC)
What are the assumptions about the temperature of the Cosmic Microwave Background being made in the Black hole evaporation section ?
At the moment, according to black hole thermodynamics, a black hole with roughly the mass of the moon has a temperature equal to that of the CMB. Larger black holes are colder than that, so are currently consuming more energy from the CMB than they would be emitting through Hawking radiation.
As I wrote previously (above, in 2006) the projection for the CMB temperature would seem to depend strongly on the scenario chosen for the continued expansion of the universe. If the universe continues to expand, so the CMB continues to fall indefinitely, then it will eventually become colder than even the largest black holes. But this is the Big Freeze scenario. If, as some posters have suggested above, the Heat Death scenario is different, and represents everything coming to the same temperature (but not zero), then that temperature would be the temperature of the largest black holes, the coldest objects in the universe, in equilbrium with the CMB.
This could use some clarification in the article. Jheald ( talk) 08:00, 17 July 2008 (UTC)
I am so sorry Spacepotato that I called you Spacepotatoe. Can you ever forgive me for calling you something so different from what your name is? I hope that this does not hurt our friendship and you can reach down into your energy reserves and find it in your big heart to forgive me. I made a big mistake and I am so very very sorry. And I promise you it will never happen again. I hope this does not affect our friendship and that we can continue to be best friends and best buddies despite this incident. Once again I am so sorry for calling you Spacepotaote, something so radically different from Spacepotato, and I implore you to find it in your heart to forgive me. I am so sorry, and I will make it up to you, please let us continue to be best friends. Thank You Maldek ( talk) 00:02, 19 July 2008 (UTC)
My thought in creating the new article, future of an expanding universe, was that the material in the timeline that is unrelated to the heat death of the universe would be moved there. There was no opposition and some support in the discussion above, which I interpreted as a clear consensus in support of this move. However, the material on the Milky Way/Andromeda collision, the coalescence of the Local Supercluster, and the graphical timeline were re-added ( diff). I undid the edit because I think the material is very clearly not on topic; am I mistaken?
I think that the timeline should be further trimmed, or maybe completely deleted, not re-expanded.
I have dramatically trimmed the timeline section and renamed it "Timeframe for heat death" because I think rewriting will help to focus the section on the heat death, not possible futures of the universe. The section could probably use some expansion (there's more material in Adams & Lauglin §VID, for example), but I don't have time to work more now. —Alex (
ASHill |
talk |
contribs)
22:02, 19 July 2008 (UTC)
I'm no Wikipedia formatting expert, so I'll just pose the question: is there a way to preserve the formatting in the "Timeline for heat death" in the table of contents on the main page? It looks like the black hole age is just 1040 years away, rather than 10^40 years away. Jyoshimi 18:42, 17 October 2006 (UTC)
Awww...crap.
Yeah, keeping it at 1040 might scare some people. —Preceding unsigned comment added by 68.227.163.40 ( talk) 03:14, 8 May 2008 (UTC)
Dear friend Spacepotato, the very article itself contains the relevant justification, if it were not obvious after a moment's reflection. Lord Kelvin is quoted as follows.
"The result would inevitably be a state of universal rest and death, if the universe were finite and left to obey existing laws. But it is impossible to conceive a limit to the extent of matter in the universe; and therefore science points rather to an endless progress, through an endless space, of action involving the transformation of potential energy into palpable motion and hence into heat, than to a single finite mechanism, running down like a clock, and stopping for ever."
This means that Kelvin simply does not know whether the universe is finite or not. He just says that it is impossible to conceive a limit to the extent of matter in the universe. He was writing before people had a sort of justification for an idea of a finite universe, inferred from the Einstein general theory of relativity and then the doctrine of the Big Bang. Kelvin's saying he cannot conceive of the contrary is his own admission that he is speculating wildly.
But then, it is literally true that the heat death of the universe is empirically unverifiable, for when it happens, there will be no one around to conduct the alleged empirical verification.
The article invites the reader to see also articles about the future of an expanding universe, quite outside the range of Kelvin's thinking. And to see articles about the big crunch, the big bounce, and the cyclic model. These are testimony to the deeply speculative nature of the grandiose conclusion that the universe will have a heat death.
The universe itself is, if it is tending to a heat death, not in thermodynamic equilibrium. But Kelvin had no definition the entropy of such a universe. He was speculating way beyond what he could prove. If one cannot see that for oneself, it would be good for one to have some warning from someone who can, by simply thinking carefully about what the article itself says.
It is not for the good of science for it to speculate and not tell people that it is doing so, but instead to give them the false impression that it is telling them about scientifically established fact. Chjoaygame ( talk) 07:30, 1 October 2009 (UTC)
Thank you for your thoughts. Chjoaygame ( talk) 01:17, 2 October 2009 (UTC)
I'm not sure it's worth adding a "references in popular culture" section to this article just for one item, but interestingly there is a play entitled Postponing the Heat Death of the Universe in which the protagonist lies perfectly still to postpone entropy. -- WayneMokane ( talk) 15:24, 7 October 2009 (UTC)
An anon removed this section. It was restored, but after reading the section and the source cited, I've reimplemented the removal.
The section's text did not match the source. Rather that describing "heat death", the first paragraph describes Olbers' paradox. The source cited attempts to make the point that a "heat death" doesn't imply a specific temperature, and that a big freeze isn't necessarily a heat death, but it does this poorly (that material is already better-covered elsewhere in the article).
End result: This subsection's first paragraph was misleading, and the second paragraph redundant. They didn't follow the source, and the material is already better-covered in other sections. So, I endorse the removal of this section. -- Christopher Thomas ( talk) 15:50, 14 May 2011 (UTC)
The history of the heat death of the universe confuses Thomson's principle of least dissipation of energy and Clausius's principle that the entropy of the universe tends to a maximum. It was Boltzmann in his public lectures who popularized the idea of the end of the universe in a heat death. P. G. Tait in his first edition of "Sketch of Thermodynamics" (1867) tried to make the principle of least dissipation stick, but it was later superseded by Clausius's principle [cf. his second edition]. Bernhlav ( talk) 07:21, 4 September 2012 (UTC)
This article is at present heavily biased to make it seem as if there is definite physical meaning in the idea of the heat death of the universe, when that is not so. My edits were intended to bring some scientific accuracy to the article. They were reverted by someone who is apparently imbued with the bias that now pervades the article.
The celebrated statements by Clausius about the energy and entropy of the universe are regarded by thermodynamicists as poetic or metaphorical, but are mistakenly taken as categorical and physically well defined by the mindset that biases the present article. This mindset is a kind of 'fundamentalism', so to speak, not in a conventional religion, but in what would like to be taken as science, but is really pseudo-science.
The concept of entropy rests on two bases. One is the definition of entropy by Clausius, in directly physical terms. It refers only to the states of systems consisting of matter and energy that are in a condition of thermodynamic equilibrium. "The universe" is not, and has never been, understood well enough to justify a statement that it is in thermodynamic equilibrium. There is no generally recognized and understood physical definition of the entropy of such vast and ill-understood entities as "the universe". The present article gives no hint of this. The other definition of entropy is much more recent, far more abstract, and not widely used. In this definition, entropy is proportional to the amount of information needed to take one's knowledge of a system, from a state of knowledge defined by the values of a set of macroscopic variables, to a state of knowledge defined by a detailed and exhaustive description of the state of the system in terms of its microscopic and elementary particulate constituents. It is not of such close relevance to the present article, but in the case of equilibrium thermodynamics it is in logical agreement with the Clausius physical definition.
The article as it stands is full of half-baked slip-shod pseudo-thinking. Chjoaygame ( talk) 21:20, 10 September 2012 (UTC)
The present article is borderline. It tries to pass off a historical or very speculative and ultimately nearly nonsensical idea as if it were more or less reliable science. It needs be edited further to indicate just how far is the idea of "heat death of the universe" from reliable science.
To add to this by a link to an account of a science fantasy gives too much credibility to that fantasy, and adds to the feeling of licence that this article has that one can talk in the Wikipedia with such a blurring of the borderline between science and fantasy.
Perhaps I went too far in calling the link vandalism. I would still remove it on the ground that it is misleading by supporting confusion of thought. Chjoaygame ( talk) 00:45, 10 December 2012 (UTC) Chjoaygame ( talk) 00:47, 10 December 2012 (UTC)
The first sentence of the lead finishes as follows: "the universe has diminished to a state of no thermodynamic free energy and therefore can no longer sustain processes that consume energy (including computation and life)." As it stands this seems to be a statement in terms of thermodynamics but in those terms it is nonsense; yes, utter nonsense; that is to say, it has no physical meaning. To find out why this is so, one must read a little thermodynamics. Chjoaygame ( talk) 17:39, 25 October 2012 (UTC)
I know a lot of predictions have been proven but how the heck is heat gonna cause the death of the universe. I personally believe that the universe is gonna exist for eternity. The universe has been expanding since the big bang, what makes you think it's gonna come to an end. It's possible that it will end, but in my opinion if it will end it won't end for billions of years. — Preceding unsigned comment added by Anastronomer ( talk • contribs) 15:48, 20 October 2012 (UTC)
I have undone the removal of a clause of a quotation. The reason given for the removal was that the clause is irrelevant to the article. But the clause modifies the meaning of the quoted words, and so is relevant to the article.
The underlying physical question is whether Clausius' use of the word universe in his famous aphorism is literally applicable to the whole actual physical universe, or whether it is simply rhetorical, "sybillic" in the words of Truesdell, or "poetic" in the words of Grandy.
Clausius is the author of the sybillic utterance, "The energy of the universe is constant; the entropy of the universe tends to a maximum." The objectives of continuum thermomechanics stop far short of explaining the "universe", but within that theory we may easily derive an explicit statement in some ways reminiscent of Clausius, but referring only to a modest object: an isolated body of finite size.
— Truesdell, C., Muncaster, R.G. (1980). Fundamentals of Maxwell's Kinetic Theory of a Simple Monatomic Gas, Treated as a Branch of Rational Mechanics, Academic Press, New York, ISBN0-12-701350-4, p.17.
This was expressed rather poetically by Clausius in his famous couplet reflecting the First and Second Laws: "Die Energie der Welt ist constant; Die Entropie der Welt strebt einem Maximum zu.
— Grandy, W.T., Jr (2008), Entropy and the Time Evolution of Macroscopic Systems, Oxford University Press, Oxford UK, ISBN 978-0-19-954617-6, p. 4.
The scope of the cited text on thermodynamics is relevant to the scope of the meaning of one of its sentences that is quoted. Chjoaygame ( talk) 22:59, 25 August 2013 (UTC)
There is a move discussion in progress on Talk:Age of the universe which affects this page. Please participate on that page and not in this talk page section. Thank you. — RMCD bot 22:15, 3 October 2013 (UTC)
Where, exactly, does this source (Treatise on Thermodynamics) say that "the phrase 'entropy of the universe' has no meaning". I searched for this, but could not find it. 214.4.238.180 ( talk) 13:17, 11 March 2014 (UTC)
With all respect to the editor who removed the paragraph that started " Ludwig Boltzmann accomplished the feat of showing that the second law of thermodynamics is only a statistical fact." The physical reality is that we have not the slightest idea of the remote future of the universe, and that talk of increase of entropy of a single object not in thermodynamic equilibrium is presumptuous at best. That the second law depends on an external driver, not present for the universe as a whole, is important to place some kind of reality check on talk of "the heat death of the universe". I think the added paragraph should stand, as a guide to the reader that we are here talking unverifiable speculation, if not nonsense. Chjoaygame ( talk) 01:21, 10 February 2014 (UTC)
The idea of heat death of the universe is of merely historical interest. The simple idea of heat death of the universe is no longer remotely tenable in serious physics, because the idea is meaningless. Yet this article continues to accumulate pretentious disorganized miscellaneous drivel as if the idea of heat death of the universe were currently a useful one. The article should confine its contents to simply historical accounts, mostly about nineteenth century thinking. Serious speculation about the remote future of the universe belongs elsewhere. For these reasons, as it stands, this article is a blot on the face of the Wikipedia. Chjoaygame ( talk) 09:13, 11 June 2014 (UTC)
The see also section has a lot of ill-relevant link and probably should be cleaned up.
Ke48273 ( talk) 00:18, 28 August 2014 (UTC)
Don't get me wrong: I think this article is a drivel magnet and is mostly misconceived. But that's not what we are concerned with right here and now. Our present concern is with a question of grammar raised by this edit. I undid the edit because I think it did not improve the article.
The verb of the sentence is 'are thought'. The tense is present. I think the English language is flexible enough to let that cover whatever is thought. The edit was redundant. Chjoaygame ( talk) 03:02, 10 January 2015 (UTC)
A lot of the later additions to this page are in poor English which creates ambiguity of meaning. They also seem to be worded more to win an argument with other editors than to contribute to a well-written article. Some are placed inappropriately to give more prominence to this argument (which is, as I understand it, that the idea of Heat Death is so clearly ridiculous that the page should make that clear from the start and throughout, or should not be here at all). The result actually weakens the article and the argument of the editor. More moderate and appropriate editing would improve both (if the argument has merit).
In a more recent view than Kelvin's, it has been recognized by a respected authority on thermodynamics, Max Planck, that the phrase 'entropy of the Universe' has no meaning because it admits of no accurate definition.[1][2] Kelvin's speculation falls with this recognition.
This has all of those problems:
The whole "Current Status" section is baggy, verbose and poorly structured. The sudden introduction of "Inflationary Cosmology", an allegedly common misunderstanding about that field and the refutation of that misunderstanding, seems to serve no purpose at all here other than rehearse arguments which annoy the editor. A series of sources are introduced mostly without any information about their authority. These would be better presented if grouped according to the main arguments they share. The section itself would also be better placed *after* the "Time Frame" section in which the idea is briefly developed. That would give more context for the counter-arguments.
The quality of this article has been damaged by the conviction of one editor that the hypothesis is not only wrong but laughable. If the counter-arguments were presented with better clarity and in a way that enhanced rather than confused the article's structure, the editor's argument would actually be better presented.
I'm going to leave this a few days to allow time for responses but then I'm going to clean this up. Itsbruce ( talk) 12:55, 22 February 2015 (UTC)
An anonymous IP editor has here deleted the sentence "In other words, this writer is saying that when gravity is taken into account (which Kelvin did not), a prediction of heat death is not justified." The deletion is covered by the edit summary "I removed original research".
The edit is faulty, because the the removed sentence was not original research. The removed sentence was re-wording of the cited source to clarify for the reader the meaning of the cited passage. Such re-wording is not original research; no, it is good editing. The re-wording clarifies for the reader the precise relevance for the article of the cited passage. Chjoaygame ( talk) 04:48, 3 April 2015 (UTC)
Looking at the present entries in the Heat death of the universe#Further reading section, I feel that none of them are suitable to be recommended by Wikipedia for this article. I would like to delete them all. Chjoaygame ( talk) 00:41, 1 April 2015 (UTC)
An edit here has an edit summary that warns against "argument from authority".
I don't intend to try to resist the author of that edit.
But it is worth noting in this context that the whole basis, without exception, of Wikipedia, is reliance on authority. It is known as the policy of reliable sourcing. Planck is a reliable source on the relevant matters. It is probably useful to bring that to the attention of a wavering reader, considering that the article partly relies on dubious sources, or even in places on no stated source. Chjoaygame ( talk) 12:05, 5 April 2015 (UTC)
It was a well intended edit, but not an improvement, to remove the statement that Planck is a respective authority in this area. Planck is a reliable source, indeed "authoritative" according to another reliable source. To help remove the worry, I have quoted Uffink explicitly on the point of authority. Uffink is currently a reliable source on such matters, having been chosen by the editors to contribute to the book in which he writes. I have corrected the English of Uffink who is, I suppose, not a native English speaker. He wrote "underestimated" where 'overestimated' is the usual cliché and the only reading that makes sense. That error of English is quite common because the phrase is cliché and people often don't put their minds in gear when using it. Chjoaygame ( talk) 08:36, 19 April 2015 (UTC)
"I think it appropriate to cite a reliable source saying that another source is authoritative."Undoubtedly, that is what you think. The problem is that what you think is wrong.-- Anders Feder ( talk) 10:26, 20 April 2015 (UTC)
http://edition.cnn.com/2015/08/10/us/universe-dying/index.html
(three sources from here: http://www.inquisitr.com/2328733/scientists-confirm-universe-is-dying/ )-- Hienafant ( talk) 23:14, 15 August 2015 (UTC)
And why was I marked as a vandal? That illustration was in my math textbook, and is of decent historical interest. Laudiacay ( talk) 16:02, 25 April 2016 (UTC)
As there are many scientific ideas about the fate of our universe, several of which have scientific backing, heat death is a hypothesis not a theory. — Preceding unsigned comment added by 51.9.160.162 ( talk) 00:06, 1 April 2017 (UTC)
The article states " Possibly another universe could be created by random quantum fluctuations or quantum tunneling in roughly years.". I have looked into the linked source, and think things got a lot simplified here. While not a being a physicist myself, I at least see only probability a value of in the linked source without a the dimension "years" linked to the value (not that it matters a lot if you have years or seconds with this huge/tiny values). Its the propability within a "space-time volume" - whatever this is. Maybe this can be explained a little better. TTL ( talk) 10:29, 3 September 2017 (UTC)
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My recent edit is NOT intended to refute the Heath Death Scenario. However, it seems that there are many theories about how the universe evolves with time, some of which posit the idea of Cyclic universes and decaying cosmological constants. We might have theoretical reasons for believing the heat death scenario is true - and, if so, we should demonstrate those reasons in the article. However, it seems as if the jury might very well still be out about whether the universe ends in a heat death. If there is room for reasonable doubt about whether this scenario is true, then reasons for doubt are best indicated (as in the Controversies section).
There is a paper entitled "Current observations with a decaying cosmological constant allow for chaotic cyclic cosmology" and another paper entitled "Decay of the cosmological constant by Hawking radiation as quantum tunneling" which may be worth further reading.
Stating that the universe ends in Heat Death is not necessarily a proven fact (though I can certainly understand why many people would jump on the 'Heat Death' bandwagon - due to the Second Law of Thermodynamics). We could argue on the 'balance of probabilities' but this might lead to erroneous conclusions.
ASavantDude ( talk) 18:07, 9 June 2018 (UTC)
I.e. the specificity is zero. There is no number. When is heat death? Can you at least provide a distribution to extrapolate from? — Preceding unsigned comment added by 2601:648:8505:2CE0:E1BD:E283:6E14:D5B1 ( talk) 00:55, 25 June 2019 (UTC)
A few years ago, I saw a documentary on the BBC, the details of which I can't remember. If I remember correctly, the documentary said that all of the mass in the universe is undergoing an extremely slow evaporation process which will eventually lead to a universe in which no particle exists other than photons. This will be the heat death of the universe.
Does anyone know exactly how this extremely slow evaporation process works? What actually happens to any particle of mass during this process? 95.172.233.137 ( talk) 12:51, 19 June 2018 (UTC)
Well anyway not everything is a liquid, so the term is definitely incorrect. — Preceding unsigned comment added by 2601:648:8505:2CE0:E1BD:E283:6E14:D5B1 ( talk) 00:57, 25 June 2019 (UTC)
I think that there should be more info here such as examples, or, well, basically more info. What do you think? MercenaryFeet ( talk) 09:44, 11 October 2020 (UTC)
A discussion is taking place to address the redirect Big Freeze. The discussion will occur at Wikipedia:Redirects for discussion/Log/2020 December 9#Big Freeze until a consensus is reached, and readers of this page are welcome to contribute to the discussion. MB 15:35, 9 December 2020 (UTC)
I noticed that, under the "Current status" section, a new paragraph was added about a recently published study. After cleaning up the grammar I looked to the actual source to read more, and I have noted that the quotes in that paragraph are not located anywhere within the academic paper that is that paragraph's sole source. In short, whoever added that section seems to have paraphrased a false quote not located within the published study (as far as I have been able to find as of yet). This should be handled and replaced with something more accurate from that study. Further, the quote by Yi-Kuan Chiang isn't located within the study either, and likely is from an entirely different source. Either way, it needs its own source as well. SpecialAgentCake ( talk) 10:48, 16 December 2020 (UTC)
All the quotes seem to come from this news release:
https://news.osu.edu/the-universe-is-getting-hot-hot-hot-a-new-study-suggests/
TChapProctor (
talk)
19:57, 21 December 2020 (UTC)
let's assume this gets worse because of climate change?? MattClowers ( talk) 16:14, 18 February 2021 (UTC)
This page is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
1. I am extremely sorry that I kept messing up the equation 10^40 plus 1.7x 10^106. I finally understand that the correct value is 1.7 followed by 65 zeros and then a one x 10^106, a very insignificant number so I also agree that it should just be kept at 1.7x 10^106. I apologize again for the erroneous corrections I have about this subject matter. I began to understand it using large numbers. I understood that 10^106 is 10^66 times larger than 10^40 thus 10^40 only represented 0.followed by 65 zeros and 1. I understand my error, so I thank you for enlightening me but there is still one thing I do not understand. You say that “So, 3^3^3 is the same as 3^(3^3), and is not the same as (3^3)^3 = 3^9.” This is not true 3^3^3 equals 19683 and 3^(3^3) equals 7.62 x 10^12. Obviously the latter number is much larger. Just type it in a graphing calculator and you can see for yourself.
2. The Poncence Recurrence time was messed up so I changed it according to the offical sources. You can see for yourself.
3. The Black Hole Lifetimes should be kept there because it is relavent to the article since different black holes evaporate at different times. You yourself Spacepotatoe have agreed upon this table since you were the one who created it.
4. The lifetime of 1.7x 10^106 years for 20 trillon solar mass black holes, was a number that Spacepotatoe said he found in a reliable source. I had originally but 10^106 years as the lifetime of 20 trillion solar mass black holes but you, Spacepotatoe said that the correct number was 1.7x 10^106 according to your source which you said was much more reliable then mine, so I accepted your word. But now Ashill says there is no source for this and that 1.7x 10^106 is to accruate to be known. I wrote 10^106 years in the first place but Spacepotatoe said he had found a source much more reliable then this so I went with this word. So this 20 trillion solar mass black hole lifetime has been sourced by me and then resourced with Spacepotatoes “much more accurate” source. Ironic how Ashill now says 1.7 x 10^106 is too accurate when I put 10^106 all along and Spacepotatoe comes along and repeatedly changes it to 1.7 x 10^106 years because he says it is much more accurate then my source. So finally I just took Spacepotatoes word, but now Ashill doesn’t like it and says its not relevant and not sourced when it is in fact both relevant and sourced even reliably sourced by Spacepotatoe. Understand that most of the information in this article is from Spacepotatoes sources so I am not supplying these reliable sources.
5. I still don’t understand why I can’t add stars are flung from their orbits in 10^18 years. It is sourced so why can’t I put that in addition your new section about Galaxy Evaporation since stars being flung from their orbits in a prerequistie to Galaxy Evaporation? Could you please tell me?
6. Why are all of things that we agreed on now being changed and if the Coalasing of the Local Group does not relate to the topic then why would Spacepotatoe add it? Please let me know for this article is getting out of control and I need some answers as to why things are being changed so much such as Black Hole Lifetime table after it had been agreed upon for so many weeks and there has been consensus on it, and now all of the sudden Ashill wants it gone. And anyway it was Spacepotatoes idea for the Table so why would he add the table if it wasn’t relevant to the article? I just need some answers? Sorry for all the questions. Thank You for you cooperation. Thank You Maldek ( talk) 01:44, 17 July 2008 (UTC)
Spelling of name of User:Spacepotato | |
Spacepotato | Spacepotatoe |
OK. Good. Right. Ça va pas mal. ¡Muy bien! |
Not OK. Bad. Wrong. Tout est perdu. Estamos en el quinto coño. |
[I transferred this question to Talk:Future of an expanding universe because although that article's content is a large portion of this one, the "heat death" scenario with maximal entropy is inconsistent with speculations about planets made out of neutrinos ;)] Wnt ( talk) 17:19, 18 July 2008 (UTC)
What are the assumptions about the temperature of the Cosmic Microwave Background being made in the Black hole evaporation section ?
At the moment, according to black hole thermodynamics, a black hole with roughly the mass of the moon has a temperature equal to that of the CMB. Larger black holes are colder than that, so are currently consuming more energy from the CMB than they would be emitting through Hawking radiation.
As I wrote previously (above, in 2006) the projection for the CMB temperature would seem to depend strongly on the scenario chosen for the continued expansion of the universe. If the universe continues to expand, so the CMB continues to fall indefinitely, then it will eventually become colder than even the largest black holes. But this is the Big Freeze scenario. If, as some posters have suggested above, the Heat Death scenario is different, and represents everything coming to the same temperature (but not zero), then that temperature would be the temperature of the largest black holes, the coldest objects in the universe, in equilbrium with the CMB.
This could use some clarification in the article. Jheald ( talk) 08:00, 17 July 2008 (UTC)
I am so sorry Spacepotato that I called you Spacepotatoe. Can you ever forgive me for calling you something so different from what your name is? I hope that this does not hurt our friendship and you can reach down into your energy reserves and find it in your big heart to forgive me. I made a big mistake and I am so very very sorry. And I promise you it will never happen again. I hope this does not affect our friendship and that we can continue to be best friends and best buddies despite this incident. Once again I am so sorry for calling you Spacepotaote, something so radically different from Spacepotato, and I implore you to find it in your heart to forgive me. I am so sorry, and I will make it up to you, please let us continue to be best friends. Thank You Maldek ( talk) 00:02, 19 July 2008 (UTC)
My thought in creating the new article, future of an expanding universe, was that the material in the timeline that is unrelated to the heat death of the universe would be moved there. There was no opposition and some support in the discussion above, which I interpreted as a clear consensus in support of this move. However, the material on the Milky Way/Andromeda collision, the coalescence of the Local Supercluster, and the graphical timeline were re-added ( diff). I undid the edit because I think the material is very clearly not on topic; am I mistaken?
I think that the timeline should be further trimmed, or maybe completely deleted, not re-expanded.
I have dramatically trimmed the timeline section and renamed it "Timeframe for heat death" because I think rewriting will help to focus the section on the heat death, not possible futures of the universe. The section could probably use some expansion (there's more material in Adams & Lauglin §VID, for example), but I don't have time to work more now. —Alex (
ASHill |
talk |
contribs)
22:02, 19 July 2008 (UTC)
I'm no Wikipedia formatting expert, so I'll just pose the question: is there a way to preserve the formatting in the "Timeline for heat death" in the table of contents on the main page? It looks like the black hole age is just 1040 years away, rather than 10^40 years away. Jyoshimi 18:42, 17 October 2006 (UTC)
Awww...crap.
Yeah, keeping it at 1040 might scare some people. —Preceding unsigned comment added by 68.227.163.40 ( talk) 03:14, 8 May 2008 (UTC)
Dear friend Spacepotato, the very article itself contains the relevant justification, if it were not obvious after a moment's reflection. Lord Kelvin is quoted as follows.
"The result would inevitably be a state of universal rest and death, if the universe were finite and left to obey existing laws. But it is impossible to conceive a limit to the extent of matter in the universe; and therefore science points rather to an endless progress, through an endless space, of action involving the transformation of potential energy into palpable motion and hence into heat, than to a single finite mechanism, running down like a clock, and stopping for ever."
This means that Kelvin simply does not know whether the universe is finite or not. He just says that it is impossible to conceive a limit to the extent of matter in the universe. He was writing before people had a sort of justification for an idea of a finite universe, inferred from the Einstein general theory of relativity and then the doctrine of the Big Bang. Kelvin's saying he cannot conceive of the contrary is his own admission that he is speculating wildly.
But then, it is literally true that the heat death of the universe is empirically unverifiable, for when it happens, there will be no one around to conduct the alleged empirical verification.
The article invites the reader to see also articles about the future of an expanding universe, quite outside the range of Kelvin's thinking. And to see articles about the big crunch, the big bounce, and the cyclic model. These are testimony to the deeply speculative nature of the grandiose conclusion that the universe will have a heat death.
The universe itself is, if it is tending to a heat death, not in thermodynamic equilibrium. But Kelvin had no definition the entropy of such a universe. He was speculating way beyond what he could prove. If one cannot see that for oneself, it would be good for one to have some warning from someone who can, by simply thinking carefully about what the article itself says.
It is not for the good of science for it to speculate and not tell people that it is doing so, but instead to give them the false impression that it is telling them about scientifically established fact. Chjoaygame ( talk) 07:30, 1 October 2009 (UTC)
Thank you for your thoughts. Chjoaygame ( talk) 01:17, 2 October 2009 (UTC)
I'm not sure it's worth adding a "references in popular culture" section to this article just for one item, but interestingly there is a play entitled Postponing the Heat Death of the Universe in which the protagonist lies perfectly still to postpone entropy. -- WayneMokane ( talk) 15:24, 7 October 2009 (UTC)
An anon removed this section. It was restored, but after reading the section and the source cited, I've reimplemented the removal.
The section's text did not match the source. Rather that describing "heat death", the first paragraph describes Olbers' paradox. The source cited attempts to make the point that a "heat death" doesn't imply a specific temperature, and that a big freeze isn't necessarily a heat death, but it does this poorly (that material is already better-covered elsewhere in the article).
End result: This subsection's first paragraph was misleading, and the second paragraph redundant. They didn't follow the source, and the material is already better-covered in other sections. So, I endorse the removal of this section. -- Christopher Thomas ( talk) 15:50, 14 May 2011 (UTC)
The history of the heat death of the universe confuses Thomson's principle of least dissipation of energy and Clausius's principle that the entropy of the universe tends to a maximum. It was Boltzmann in his public lectures who popularized the idea of the end of the universe in a heat death. P. G. Tait in his first edition of "Sketch of Thermodynamics" (1867) tried to make the principle of least dissipation stick, but it was later superseded by Clausius's principle [cf. his second edition]. Bernhlav ( talk) 07:21, 4 September 2012 (UTC)
This article is at present heavily biased to make it seem as if there is definite physical meaning in the idea of the heat death of the universe, when that is not so. My edits were intended to bring some scientific accuracy to the article. They were reverted by someone who is apparently imbued with the bias that now pervades the article.
The celebrated statements by Clausius about the energy and entropy of the universe are regarded by thermodynamicists as poetic or metaphorical, but are mistakenly taken as categorical and physically well defined by the mindset that biases the present article. This mindset is a kind of 'fundamentalism', so to speak, not in a conventional religion, but in what would like to be taken as science, but is really pseudo-science.
The concept of entropy rests on two bases. One is the definition of entropy by Clausius, in directly physical terms. It refers only to the states of systems consisting of matter and energy that are in a condition of thermodynamic equilibrium. "The universe" is not, and has never been, understood well enough to justify a statement that it is in thermodynamic equilibrium. There is no generally recognized and understood physical definition of the entropy of such vast and ill-understood entities as "the universe". The present article gives no hint of this. The other definition of entropy is much more recent, far more abstract, and not widely used. In this definition, entropy is proportional to the amount of information needed to take one's knowledge of a system, from a state of knowledge defined by the values of a set of macroscopic variables, to a state of knowledge defined by a detailed and exhaustive description of the state of the system in terms of its microscopic and elementary particulate constituents. It is not of such close relevance to the present article, but in the case of equilibrium thermodynamics it is in logical agreement with the Clausius physical definition.
The article as it stands is full of half-baked slip-shod pseudo-thinking. Chjoaygame ( talk) 21:20, 10 September 2012 (UTC)
The present article is borderline. It tries to pass off a historical or very speculative and ultimately nearly nonsensical idea as if it were more or less reliable science. It needs be edited further to indicate just how far is the idea of "heat death of the universe" from reliable science.
To add to this by a link to an account of a science fantasy gives too much credibility to that fantasy, and adds to the feeling of licence that this article has that one can talk in the Wikipedia with such a blurring of the borderline between science and fantasy.
Perhaps I went too far in calling the link vandalism. I would still remove it on the ground that it is misleading by supporting confusion of thought. Chjoaygame ( talk) 00:45, 10 December 2012 (UTC) Chjoaygame ( talk) 00:47, 10 December 2012 (UTC)
The first sentence of the lead finishes as follows: "the universe has diminished to a state of no thermodynamic free energy and therefore can no longer sustain processes that consume energy (including computation and life)." As it stands this seems to be a statement in terms of thermodynamics but in those terms it is nonsense; yes, utter nonsense; that is to say, it has no physical meaning. To find out why this is so, one must read a little thermodynamics. Chjoaygame ( talk) 17:39, 25 October 2012 (UTC)
I know a lot of predictions have been proven but how the heck is heat gonna cause the death of the universe. I personally believe that the universe is gonna exist for eternity. The universe has been expanding since the big bang, what makes you think it's gonna come to an end. It's possible that it will end, but in my opinion if it will end it won't end for billions of years. — Preceding unsigned comment added by Anastronomer ( talk • contribs) 15:48, 20 October 2012 (UTC)
I have undone the removal of a clause of a quotation. The reason given for the removal was that the clause is irrelevant to the article. But the clause modifies the meaning of the quoted words, and so is relevant to the article.
The underlying physical question is whether Clausius' use of the word universe in his famous aphorism is literally applicable to the whole actual physical universe, or whether it is simply rhetorical, "sybillic" in the words of Truesdell, or "poetic" in the words of Grandy.
Clausius is the author of the sybillic utterance, "The energy of the universe is constant; the entropy of the universe tends to a maximum." The objectives of continuum thermomechanics stop far short of explaining the "universe", but within that theory we may easily derive an explicit statement in some ways reminiscent of Clausius, but referring only to a modest object: an isolated body of finite size.
— Truesdell, C., Muncaster, R.G. (1980). Fundamentals of Maxwell's Kinetic Theory of a Simple Monatomic Gas, Treated as a Branch of Rational Mechanics, Academic Press, New York, ISBN0-12-701350-4, p.17.
This was expressed rather poetically by Clausius in his famous couplet reflecting the First and Second Laws: "Die Energie der Welt ist constant; Die Entropie der Welt strebt einem Maximum zu.
— Grandy, W.T., Jr (2008), Entropy and the Time Evolution of Macroscopic Systems, Oxford University Press, Oxford UK, ISBN 978-0-19-954617-6, p. 4.
The scope of the cited text on thermodynamics is relevant to the scope of the meaning of one of its sentences that is quoted. Chjoaygame ( talk) 22:59, 25 August 2013 (UTC)
There is a move discussion in progress on Talk:Age of the universe which affects this page. Please participate on that page and not in this talk page section. Thank you. — RMCD bot 22:15, 3 October 2013 (UTC)
Where, exactly, does this source (Treatise on Thermodynamics) say that "the phrase 'entropy of the universe' has no meaning". I searched for this, but could not find it. 214.4.238.180 ( talk) 13:17, 11 March 2014 (UTC)
With all respect to the editor who removed the paragraph that started " Ludwig Boltzmann accomplished the feat of showing that the second law of thermodynamics is only a statistical fact." The physical reality is that we have not the slightest idea of the remote future of the universe, and that talk of increase of entropy of a single object not in thermodynamic equilibrium is presumptuous at best. That the second law depends on an external driver, not present for the universe as a whole, is important to place some kind of reality check on talk of "the heat death of the universe". I think the added paragraph should stand, as a guide to the reader that we are here talking unverifiable speculation, if not nonsense. Chjoaygame ( talk) 01:21, 10 February 2014 (UTC)
The idea of heat death of the universe is of merely historical interest. The simple idea of heat death of the universe is no longer remotely tenable in serious physics, because the idea is meaningless. Yet this article continues to accumulate pretentious disorganized miscellaneous drivel as if the idea of heat death of the universe were currently a useful one. The article should confine its contents to simply historical accounts, mostly about nineteenth century thinking. Serious speculation about the remote future of the universe belongs elsewhere. For these reasons, as it stands, this article is a blot on the face of the Wikipedia. Chjoaygame ( talk) 09:13, 11 June 2014 (UTC)
The see also section has a lot of ill-relevant link and probably should be cleaned up.
Ke48273 ( talk) 00:18, 28 August 2014 (UTC)
Don't get me wrong: I think this article is a drivel magnet and is mostly misconceived. But that's not what we are concerned with right here and now. Our present concern is with a question of grammar raised by this edit. I undid the edit because I think it did not improve the article.
The verb of the sentence is 'are thought'. The tense is present. I think the English language is flexible enough to let that cover whatever is thought. The edit was redundant. Chjoaygame ( talk) 03:02, 10 January 2015 (UTC)
A lot of the later additions to this page are in poor English which creates ambiguity of meaning. They also seem to be worded more to win an argument with other editors than to contribute to a well-written article. Some are placed inappropriately to give more prominence to this argument (which is, as I understand it, that the idea of Heat Death is so clearly ridiculous that the page should make that clear from the start and throughout, or should not be here at all). The result actually weakens the article and the argument of the editor. More moderate and appropriate editing would improve both (if the argument has merit).
In a more recent view than Kelvin's, it has been recognized by a respected authority on thermodynamics, Max Planck, that the phrase 'entropy of the Universe' has no meaning because it admits of no accurate definition.[1][2] Kelvin's speculation falls with this recognition.
This has all of those problems:
The whole "Current Status" section is baggy, verbose and poorly structured. The sudden introduction of "Inflationary Cosmology", an allegedly common misunderstanding about that field and the refutation of that misunderstanding, seems to serve no purpose at all here other than rehearse arguments which annoy the editor. A series of sources are introduced mostly without any information about their authority. These would be better presented if grouped according to the main arguments they share. The section itself would also be better placed *after* the "Time Frame" section in which the idea is briefly developed. That would give more context for the counter-arguments.
The quality of this article has been damaged by the conviction of one editor that the hypothesis is not only wrong but laughable. If the counter-arguments were presented with better clarity and in a way that enhanced rather than confused the article's structure, the editor's argument would actually be better presented.
I'm going to leave this a few days to allow time for responses but then I'm going to clean this up. Itsbruce ( talk) 12:55, 22 February 2015 (UTC)
An anonymous IP editor has here deleted the sentence "In other words, this writer is saying that when gravity is taken into account (which Kelvin did not), a prediction of heat death is not justified." The deletion is covered by the edit summary "I removed original research".
The edit is faulty, because the the removed sentence was not original research. The removed sentence was re-wording of the cited source to clarify for the reader the meaning of the cited passage. Such re-wording is not original research; no, it is good editing. The re-wording clarifies for the reader the precise relevance for the article of the cited passage. Chjoaygame ( talk) 04:48, 3 April 2015 (UTC)
Looking at the present entries in the Heat death of the universe#Further reading section, I feel that none of them are suitable to be recommended by Wikipedia for this article. I would like to delete them all. Chjoaygame ( talk) 00:41, 1 April 2015 (UTC)
An edit here has an edit summary that warns against "argument from authority".
I don't intend to try to resist the author of that edit.
But it is worth noting in this context that the whole basis, without exception, of Wikipedia, is reliance on authority. It is known as the policy of reliable sourcing. Planck is a reliable source on the relevant matters. It is probably useful to bring that to the attention of a wavering reader, considering that the article partly relies on dubious sources, or even in places on no stated source. Chjoaygame ( talk) 12:05, 5 April 2015 (UTC)
It was a well intended edit, but not an improvement, to remove the statement that Planck is a respective authority in this area. Planck is a reliable source, indeed "authoritative" according to another reliable source. To help remove the worry, I have quoted Uffink explicitly on the point of authority. Uffink is currently a reliable source on such matters, having been chosen by the editors to contribute to the book in which he writes. I have corrected the English of Uffink who is, I suppose, not a native English speaker. He wrote "underestimated" where 'overestimated' is the usual cliché and the only reading that makes sense. That error of English is quite common because the phrase is cliché and people often don't put their minds in gear when using it. Chjoaygame ( talk) 08:36, 19 April 2015 (UTC)
"I think it appropriate to cite a reliable source saying that another source is authoritative."Undoubtedly, that is what you think. The problem is that what you think is wrong.-- Anders Feder ( talk) 10:26, 20 April 2015 (UTC)
http://edition.cnn.com/2015/08/10/us/universe-dying/index.html
(three sources from here: http://www.inquisitr.com/2328733/scientists-confirm-universe-is-dying/ )-- Hienafant ( talk) 23:14, 15 August 2015 (UTC)
And why was I marked as a vandal? That illustration was in my math textbook, and is of decent historical interest. Laudiacay ( talk) 16:02, 25 April 2016 (UTC)
As there are many scientific ideas about the fate of our universe, several of which have scientific backing, heat death is a hypothesis not a theory. — Preceding unsigned comment added by 51.9.160.162 ( talk) 00:06, 1 April 2017 (UTC)
The article states " Possibly another universe could be created by random quantum fluctuations or quantum tunneling in roughly years.". I have looked into the linked source, and think things got a lot simplified here. While not a being a physicist myself, I at least see only probability a value of in the linked source without a the dimension "years" linked to the value (not that it matters a lot if you have years or seconds with this huge/tiny values). Its the propability within a "space-time volume" - whatever this is. Maybe this can be explained a little better. TTL ( talk) 10:29, 3 September 2017 (UTC)
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My recent edit is NOT intended to refute the Heath Death Scenario. However, it seems that there are many theories about how the universe evolves with time, some of which posit the idea of Cyclic universes and decaying cosmological constants. We might have theoretical reasons for believing the heat death scenario is true - and, if so, we should demonstrate those reasons in the article. However, it seems as if the jury might very well still be out about whether the universe ends in a heat death. If there is room for reasonable doubt about whether this scenario is true, then reasons for doubt are best indicated (as in the Controversies section).
There is a paper entitled "Current observations with a decaying cosmological constant allow for chaotic cyclic cosmology" and another paper entitled "Decay of the cosmological constant by Hawking radiation as quantum tunneling" which may be worth further reading.
Stating that the universe ends in Heat Death is not necessarily a proven fact (though I can certainly understand why many people would jump on the 'Heat Death' bandwagon - due to the Second Law of Thermodynamics). We could argue on the 'balance of probabilities' but this might lead to erroneous conclusions.
ASavantDude ( talk) 18:07, 9 June 2018 (UTC)
I.e. the specificity is zero. There is no number. When is heat death? Can you at least provide a distribution to extrapolate from? — Preceding unsigned comment added by 2601:648:8505:2CE0:E1BD:E283:6E14:D5B1 ( talk) 00:55, 25 June 2019 (UTC)
A few years ago, I saw a documentary on the BBC, the details of which I can't remember. If I remember correctly, the documentary said that all of the mass in the universe is undergoing an extremely slow evaporation process which will eventually lead to a universe in which no particle exists other than photons. This will be the heat death of the universe.
Does anyone know exactly how this extremely slow evaporation process works? What actually happens to any particle of mass during this process? 95.172.233.137 ( talk) 12:51, 19 June 2018 (UTC)
Well anyway not everything is a liquid, so the term is definitely incorrect. — Preceding unsigned comment added by 2601:648:8505:2CE0:E1BD:E283:6E14:D5B1 ( talk) 00:57, 25 June 2019 (UTC)
I think that there should be more info here such as examples, or, well, basically more info. What do you think? MercenaryFeet ( talk) 09:44, 11 October 2020 (UTC)
A discussion is taking place to address the redirect Big Freeze. The discussion will occur at Wikipedia:Redirects for discussion/Log/2020 December 9#Big Freeze until a consensus is reached, and readers of this page are welcome to contribute to the discussion. MB 15:35, 9 December 2020 (UTC)
I noticed that, under the "Current status" section, a new paragraph was added about a recently published study. After cleaning up the grammar I looked to the actual source to read more, and I have noted that the quotes in that paragraph are not located anywhere within the academic paper that is that paragraph's sole source. In short, whoever added that section seems to have paraphrased a false quote not located within the published study (as far as I have been able to find as of yet). This should be handled and replaced with something more accurate from that study. Further, the quote by Yi-Kuan Chiang isn't located within the study either, and likely is from an entirely different source. Either way, it needs its own source as well. SpecialAgentCake ( talk) 10:48, 16 December 2020 (UTC)
All the quotes seem to come from this news release:
https://news.osu.edu/the-universe-is-getting-hot-hot-hot-a-new-study-suggests/
TChapProctor (
talk)
19:57, 21 December 2020 (UTC)
let's assume this gets worse because of climate change?? MattClowers ( talk) 16:14, 18 February 2021 (UTC)