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This article describes a dark universe in which neutrinos move aimlessly without interaction. I was doing a back of the envelope calculation (purely for purposes of conversation). Based on neutrino, there are three masses of neutrinos and assuming that the lowest is very light, the second should be roughly 0.009 eV. According to escape velocity, the radius in which one neutrino gravitationally captures another should be roughly 2.1^10-42 (m^3/s^2) /(velocity^2). For two such neutrinos to form orbits 1 meter in radius, they should travel around 1.4 ^ 10-21 m/s. This implies a relativistic gamma factor = 1/sqrt (1-((1.4*10^-21)/(3*10^8))^2) = 1+1.1*10^-30 , which multiplied by the presumed 0.009 eV rest mass gets a thermal energy of 1*10^-32 eV. Now a hole in this math is that I don't understand how to apply the conversion factor for non-relativistic neutrinos at cosmic neutrino background, but if I ignore it entirely (which makes this take longer) and assume a flat expanding universe, then I want the current 1.9 K temperature (2.45 * 10^-4 eV) to cool down by a factor of 2.48 * 10^-28, i.e. for the universe to be that much bigger and that much older, at 2.5*10^38 years in the future -- times however many meters it will take then to find two adjacent neutrinos, which I can't even start to guess.
Now I'm not a physicist, so I doubt I'm breaking new ground here - has anyone considered what happens when neutrinos get cool enough to stick together? Do you get neutrino "planets"? Should they exhibit some sort of ultra-weak "chemical" (or "nuclear") forces toward one another once they sit next to each other? Wnt ( talk) 04:39, 17 July 2008 (UTC)
Apparently we're just continuing the edit war here.
I have a number of concerns about this series of edits; an incomplete list of them is below. Essentially all of these concerns were discussed at Talk:heat death of the universe before the timeline was moved into this separate article, and I do not believe the concerns have been satisfactorily addressed. I have marked the edits that I have reverted because I do not believe reasonable people can disagree on; I'll hold off on reverting others.
Note that mentioning a source in the edit summary is not sufficient because it doesn't help readers and is only marginally helpful to other editors; a source needs to be cited for every paragraph and fact in the article.
I must express some frustration: these concerns have been expressed many, many times by multiple editors, and yet the same issues keep getting re-added to the article. I would at least copy-edit the rest of the article (which is now in pretty sorry shape, formatting-wise), but I won't bother because experience tells me that my changes will be reverted as a matter of course. I would appreciate concise replies to the concerns listed here, rather than a continued edit war. —Alex ( ASHill | talk | contribs) 06:27, 20 July 2008 (UTC)
I undid these two edits.
Okay well I thought I had already explained my edits many times before but since you keep asking I will try to explain them again.
1. First of all Freeman Dyson in his report “Time without End” clearly states that star formation will end in 10^14 years so this value should be used. In addition to what Dyson says I also have sources I found that give 100 trillion years as the end of star formation by researching. Here they are: http://cedarlounge.wordpress.com/2008/02/27/when-stars-fade-out-a-disturbing-prediction-of-the-future-of-the-universe-but-a-consoling-thought-about-our-present/
http://www.astrosociety.org/pubs/mercury/0001/cosmic.html http://www.physicsbookstore.org/0684865769.html
http://spiff.rit.edu/classes/phys240/lectures/future/future.html
2. Secondly I have already given you reliable sources that claim that the longest-lived red dwarfs have a lifespan of over 100 trillion years. Here they are: http://filer.case.edu/sjr16/stars_lifedeath.html http://filer.case.edu/~sjr16/advanced/stars_avgdeath.html These are reliable sources. Why do you always say that the sources I find are not reliable? Why aren’t these sources reliable?
3. Thirdly, if Star formation ceases in 100 trillion years and the longest-lived red dwarfs have a lifespan of over 100 trilllion years, simple mathematics will prove that all stars will be gone in at least 200 trillion years. In addition to this simple math I also have sources that state this too. Here they are: http://emptv.com/print/334 http://emptv.com/in/science
4. Fourthly, I will mention that I have found many sources that state that in 3 trillion years an observer in our galaxy will not be able to see galaxies beyond our own because all other galaxies would have receded beyond the cosmic horizon. I have many sources that claim a date of 3 trillion years for this but you keep saying that it is 2 trillion years despite all my sources. Here are my sources which claim that in 3 trillion years our galaxy will be the only galaxy visible to an observer on our galaxy: http://www.universetoday.com/2007/05/22/the-universe-will-appear-static-in-3-trillion-years/ http://www.sciencedaily.com/releases/2007/05/070524094126.htm http://www.theallineed.com/astronomy/07060501.htm http://www.newuniverse.co.uk/n-archive_644.html http://www.saao.ac.za/assa/features/cosmology-articles/end.html http://www.universetoday.com/2007/07/25/the-end-of-everything/ What’s wrong with all of these sources? 5. Fifthly, why are you getting rid of the Black Hole Chart. The Black Hole Chart is good and should be kept because it helps people understand when different mass black holes disintrate. 6. Sixthly, The Poincare Recurrence time of the Universe means the time when the Universe will return back to the way that it currently is. That means the Universe will return back to the way it is now. I have found a couple of sources on the Poincare Recurrence time of the Universe at it specifically states that the Poincare Recurrence time of the Universe is 10^10^10^10^10^1.1 years. This information is from “INFORMATION LOSS IN BLACK HOLES AND/OR CONSCIOUS BEINGS? ∗”By Don N. Page:CIAR Cosmology Program, Institute for Theoretical PhysicsDepartment of Physics, University of Alberta Edmonton, Alberta, Canada T6G 2J1. Here are my sources: http://arxiv.org/abs/hep-th/9411193v2 http://www.fpx.de/fp/Fun/Googolplex/GetAGoogol.html
The Poincare Recurrence time of the Universe is when the Universe goes back to the way it currently is now. It is when the Univerese will enter its next Stelliferous Era since we are currently in the Stelliferous Era. The Poincare Recurrence time is how long it will take for the Universe to return to the way it currently is, which is in the Stelliferous Era. This is the idea of the Poincare Reccurence time of the Universe. I hope you understand this but if you need more clarification I would be happy to go into greater depths. To reitterate basically The Poincare Reccurece time of the Universe will be the next Stelliferous Era because the Universe goes in Cycles.
If you have any more questions about my edits feel free to ask. Thank you very much for your cooperation. Maldek2 ( talk) 05:26, 6 August 2008 (UTC)
Some additions to Spacepotato's comments, with which I fully agree:
Maldek, please read WP:reliable sources; the term reliable source has a specific meaning on Wikipedia, essentially that a reliable source should be published. As multiple editors, including me, have explained before, blogs are almost never reliable sources because they are self-published; the space.rit.edu, filer.case.edu, and fpx.de sources are all also self-published sources. For scientific articles, papers in peer-reviewed academic journals are generally best.
1. The sources you cite all talk explicitly about the Adams & Laughlin formulation of the ages of the universe and cite their work! It's best to use the original source, which is published in a peer-reviewed journal, instead of these sources which are based on the original source.
4. Although spacepotato's comment above illustrates the problems with your sources, you didn't actually cite those sources in the revisions you made to the article. Instead, you left in the citation of Krauss & Starkman 2000 ( DOI:10.1086/308434), which says "In a little less than 2 trillion years, all extrasupercluster objects will have redshifted by a factor of more than 1053. Even for the highest energy gamma rays, a redshift of 1053 stretches their wavelength to greater than the physical diameter of the horizon.... The resolution time for such radiation will exceed the physical age of the universe." [emphasis added] Citing that source to say that 3 trillion years is the appropriate number is false. —Alex ( ASHill | talk | contribs) 21:11, 6 August 2008 (UTC)
The subsection on decay of iron stars into black holes (in the "Future without Proton Decay" section) seems to suggest it would take longer for them to decay into neutron stars than it would for them to decay into black holes. I would think it would be the other way around, and it was for this reason that I tried to add a different figure citing "The Universe" by Colin Ronan, ISBN 0028655915-- Robert Treat ( talk) 17:14, 14 September 2008 (UTC)
I read the article you cited. I noticed it describes neutron stars forming in 101600 years, and says that these in turn will collapse into black holes in 101076 years.
Ronan doesn’t use footnotes, but he does have a bibliography at the end of his book listing other books and websites. The Dyson article isn’t listed, but maybe one of those sources lists it. If Ronan uses Professor Cramer's article, he would appear to have gotten it from a URL other than the University of Washington webpage.
Neutron star formation, in this instance, seems to me an extension of the cold fusion process that produces iron and nickel. These elements go on and fuse into neutronium.
Something I must confess to being a little curious about. 101600 years looks like it would be shortly after 101500 years. It's not, it's a googol times further into the future, but the way it's written suggests it's shortly after. I was thinking, is there any chance this figure could have been left out when they made the online version of Dyson's article?-- Robert Treat ( talk) 19:04, 15 October 2008 (UTC)
What did Dyson mean by the phrase "an unsymmetrical mode of collapse passing over a lower saddle point than the symmetric mode"?-- Robert Treat ( talk) 05:17, 9 November 2008 (UTC)
Is obviously vandalising this article. Can someone request a ban, I don't have time. WikiReverter ( talk) 04:01, 28 October 2008 (UTC)
The article describes the universe as accelerating in its expansion. However, it also describes that the local galaxies such as Milky Way and Andromeda are moving toward each other because of gravitational attraction. If this gravitational acceleration is taking place, could it be influencing our reading of the more distant galaxies by making it appear they are accelerating away from us?-- Robert Treat ( talk) 06:39, 30 November 2008 (UTC)
We know that free neutrons have a finite lifespan while those bound in nuclei are much more stable. Could it also be that free protons will be more likely to decay over the eons than bound ones? See The Half-Life of Proton Decay and its Relation to the "Heat Death" of the Universe-- Robert Treat ( talk) 21:43, 17 September 2008 (UTC).
The proton decay#experimental evidence section indicates the proton has a half-life of at least 1035 years, and I feel this article should relfect that-- Robert Treat ( talk) 07:24, 16 January 2009 (UTC).
seems pretty dumb: "Once the last star has exhausted its fuel, stars will then cease to shine." i don't know how you guys prefer to edit that stuff but i just wanted to point this out in a helpful fashion instead of vandalizing the page over and over for once —Preceding unsigned comment added by 24.56.7.231 ( talk) 01:51, 29 March 2009 (UTC)
This presents another question could the bible be correct when it says that evn the stars will wearout and die funny alos how the old things are gone with great heat anda new universe is created could this mean that at least one proton crashes into anothr at planick scale enrgy causing a new in flating universe ?/ interesting —Preceding
unsigned comment added by
74.229.22.19 (
talk)
20:58, 13 May 2009 (UTC)
The line "Assuming that dark energy continues to make the universe expand at an accelerating rate, 2×1012 (2 trillion) years from now, all galaxies outside the Local Supercluster will be red-shifted to such an extent that even gamma rays they emit will have wavelengths longer than the size of the observable universe of the time" implies that galactic red-shifting will eventually make them invisible at any wavelength. If they're red-shifted, I thought it would be the radio waves that disappear last, as gamma rays are on the "bluest" end of the spectrum. I didn't edit the article because I don't make edits anymore unless I'm absolutely 100% sure, but wanted to bring it up just in case. Thanks! - jeff ( talk) 18:33, 25 June 2009 (UTC)
This article is soo biased, on the side of ignorance, it is unbelievable. It says "planets will drop from their orbits" in 10^15 years, while this, due to gravitational radiation, is on the order 10 magnitudes greater (for Earth at least, if it weren't swallowed by Sun). It says that objects in Galaxies will relax to a Maxwell like distributions (misquoting an obscure Indian journal), which is laconic POV nonsense statement. It tosses speculation along with scientific facts and scientific hypothesis (iron stars, quantum tunneling liquids - what a load of crap). Poor, biased, sensationalism - horrible article.— Preceding unsigned comment added by 109.121.74.189 ( talk • contribs) 03:05, 17 March 2011
This article draws most of its info from Adams and Laughlin's "Five Ages of the Universe", whereas Timeline of the far future draws most of its comparable info from Freeman Dyson's "Physics and Biology in an Open Universe". I am the principle editor of Timeline of the far future; however I did not compose the information drawn from that source. Since the two contradict one another, I was wondering which was more reliable. Serendi pod ous 06:49, 14 May 2011 (UTC)
Sorry people, but i must laugh at that sentence. People, the *whole article* is speculative! (that is not necessarily bad, but the speculation does not start after the dark age.) -- 81.217.14.229 ( talk) 06:39, 24 May 2011 (UTC)
I think this page should cite roughly when the universe will achieve true heat death. Serendi pod ous 14:20, 22 June 2011 (UTC)
The statement "Photons, neutrinos, electrons, and positrons will fly from place to place, hardly ever encountering each other." seems to be contradicted by the theory of accelerons and " neutrino nuggets". [8], [9] I started a thread at the Science Refdesk called "neutrino chemistry" about this (can't usefully link to it until it's archived). I don't have the sources or the understanding to add this, but I suspect the future of the universe could be altogether more interesting than this article implies. Wnt ( talk) 22:08, 16 September 2011 (UTC)
The concept that after eventually galaxies would accelerate away from us so fast that they could not be observed is flawed. Basically the premise is that the light leaving them will be more and more red shifted. To eventually even light from the closest galaxy would be too red shifted to be observable. The flaw in this premise, is assuming that light is the only way to detect distant galaxies. Consider, today we can see galaxies in telescopes more than 10 billion light years away formed in the early universe. While it is true that light from these distant galaxies will be more shifted over time, so eventually we could not see light from those galaxies, imagine if a high energy non-zero rest mass particle left at the same time. Unlike light, this massive particle cannot be red shifted into being completely unobservable. However, the massive particle could eventually be accelerated away from us. Lets say for example the non-zero rest mass particle headed at us at nearly 100% of the speed of light. Then the particle would arrive at nearly the same time as the observable light and we would not be able to use it to observe the galaxy in the future. However, say it heads at slightly slower. Then it will arrive with a time delay. Essentially there is some minimum velocity it needs to arrive eventually, anything less will eventually be pulled away from us. Think of this like an escape velocity. A particle that had exactly the right velocity to reach us, would do so in an infinite amount of time. Those with something close to that velocity would arrive in the extremely distant future. Of course if these non-zero rest mass particles decay in route, we might only detect the decay products rather that the original particles themselves. Even more food for thought, consider the implication if light itself has a non-zero rest mass. Bill C. Riemers ( talk) 19:57, 24 July 2011 (UTC)
Christopher Thomas here makes valid points that Bill C Reimers does not respond to. One reference would be Brian Schmidt, the person who viewed the supernova redshifts, who is quoted as saying something like, "in 150 billion years our night sky will be dark except for the light from the Milky Way and Andromeda galaxies, because the light from further will never reach here." This quote is from 2002 Discover Magazine September. Extrapolating, there would be a time, not much later, when light from any star will never reach its planets. Then not much later, energy from within the star would never reach other parts of the star. It seems silly to me to speak of any events after this time. This would cut the timeline on this page far far shorter. P.M. — Preceding unsigned comment added by Healingbrain ( talk • contribs) 17:03, 24 October 2011 (UTC)
The current version of the article states that, assuming accelerating expansion, that galaxies outside the local supercluster (should that be local group?) would vanish. Shouldn't all gravitationally unbound structures eventually disconnect in this way? Doesn't that have implications for what follows?
It sounds to me like it goes something like this: after dynamical relaxation, each remnant is disconnected. These separate universes have somewhat different fates. A disconnected evaporating black hole sends radiation into nothing. The other universes decay differently, depending on proton decay ... blah blah ... Ultimately each stable elementary particle is alone in its own universe, and never runs into anything (so not "hardly ever" but never, and the bit about positronium is flat out wrong). Well except the odd quantum event, but again, unless the result of that is somehow gravitationally bound, the bits just fly off and disconnect. The end.
But I'm an amateur, and this is just my guess, maybe informed by something I read but damned if I remember. Still, I do wonder if maybe some of the stuff in the article is sourced from somewhat older material that didn't really take dark energy into account.
-- 174.118.1.24 ( talk) 04:30, 12 August 2012 (UTC)
We have in the article: "As the black hole's mass decreases, its temperature increases, becoming comparable to the Sun's by the time the black hole mass has decreased to 10^19 kilograms. The hole then provides a temporary source of light during the general darkness of the Black Hole Era."
Well, that's true enough I suppose, but don't get out the Soundgarden albums just yet. I got excited at this, since 10^19 kilos is enough mass to supply the Sun's output for a good long time. But we won't have a sky full of black holes bright as the sun, warming over the long-dead planets for a second lease of life. A black hole of 2x10^19 kg has about the same temperature as the surface of the Sun, but it is far smaller - Schwarzschild radius about 30nm. With so small a radiating surface, it puts out 0.8 microwatts. It would be difficult to warm yourself beside this meagre candle.
Wait rather longer and a black hole will reach the _luminosity_ of the Sun, putting out enough power to illuminate a whole solar system. At a temperature north of 10^20 kelvin, you'd better be an enthusiast for gamma rays. If you're not so keen, just take cover. It'll only last another 70 nanoseconds.
http://xaonon.dyndns.org/hawking/
149.241.212.44 ( talk) 20:13, 1 October 2012 (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 04:00, 3 October 2013 (UTC)
There is currently a discussion about the capitalization of Universe at Wikipedia talk:Manual of Style/Capital letters § Capitalization of universe. Please feel free to comment there. — sroc 💬 13:15, 19 January 2015 (UTC)
Lol. I thought you were talking about a universe filled with intelligent life and capital goods - a different universe from the lifeless, mindless one described in the article. Doubledork ( talk) 19:05, 1 April 2015 (UTC)
"It will then be impossible for events in the local group to affect other galaxies" - Because no one anywhere in the universe, over 1,000,000,000,000 years, can figure out how to build an Alcubierre drive or manipulate the metric tensor / expansion of space in any way. Doubledork ( talk) 19:18, 1 April 2015 (UTC)
http://apod.nasa.gov/apod/ap151206.html
70.189.251.205 ( talk) 11:50, 10 December 2015 (UTC)
Should this article really be using flowery language such as calling the photon "lovely", or text like "... but even these giants are not immortal.", even in image captions? At the risk of possibly being the killjoy, I propose to change this prose. 96.237.166.57 ( talk) 17:21, 20 July 2016 (UTC)
Under Stellar remnants escape galaxies or fall into black holes, there's a redlink to dynamical relaxation. Looking around, it appears that this should be dynamic relaxation, which does have an article associated with it. Is this correct? Laefk ( talk) 17:24, 20 July 2016 (UTC)
In the section 3.5 Beyond, it is stated that the timeframe for a possible new Big Bang is 101056 years.
However, in the cited paper by Carroll and Chen the probability is stated as P ∼ 10-101056 which is the inverse of 10101056, that is 1/(10101056)
Would not the matching timeframe to realize the probability be 10101056? Tensegrity ( talk • contribs) 20:51, 11 October 2016 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
Why won't there be anymore nucleons in the universe? Evaporating black holes create protons in the last stage of evaporating. 32ieww ( talk) 18:57, 26 February 2017 (UTC)
Example: The article about "Andromeda–Milky Way collision" does state another speed of movement of the 2 galaxies coming closer. Please check that. E.g. if you take the time 4*10^9 years and the distance 2,5*10^6 light years as given, then you can compute the velocity. Would of course be very dubious if you computed this way.
— Preceding unsigned comment added by 88.78.31.168 ( talk • contribs) 00:43, 8 October 2014 (UTC)
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The convergence of the Hubble Parameter to a future value of 55.4 km/s/Mpc implies the universe will double in size every ~12.2 billion years. After 10100 years, the universe will have expanded by a factor of more than (and by 10200 years, by ).
An estimate of the average particle density (~) after such immense expansion suggests the universe will be nearly pure vacuum. Given that estimates of the future size of the cosmological event horizon converge to ~16 Gly, and also the estimate of a total of 1097 subatomic particles in the universe, it would seem that almost all such particles would be forever removed from the possibility of interaction with other particles, and the chance of particle collision would be beyond unlikely and continuing to decline exponentially with the continued expansion of the universe. Even if there were 10100,000 subatomic particles, most such regions of ~(16 Gly)3 would be absent any particles of all. (It really doesn't matter what the exponent is of the subatomic particle estimate is, if expressed directly in decimal form - the result doesn't appreciably change. Similarly even if you increased the radius of the event horizon to Gly, most such regions are still unlikely to contain any particles).
Rsbaker0 ( talk) 14:34, 25 March 2019 (UTC)
The text added several hours ago seems to be a paraphrased version of narration in the YouTube video “TIMELAPSE OF THE FUTURE” by melodysheep https://m.youtube.com/watch?v=uD4izuDMUQA
I’m unsure if a YouTube video is generally an acceptable reference for Wikipedia. If it is, the video is linked above and takes you to YouTube.
Savie Kumara ( meow) 02:33, 24 June 2020 (UTC)