Talk:Heat death of the universe/Archive 1

Archive 1

Archive 2

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Few questions here

Why no criticism section?

One of my favorite parts of a wikipedia science page is that an unbiased representation of every idea is usually presented. I find it difficult to believe either that there aren't any physics students, professional researchers, or armchair philosophers with internet connections out there that have produced significantly viewable and researchable material on the (at least percieved) inconsistencies and flaws in one of the most celebrated ideas in modern science and science fiction. It is conspicuously absent on this page. There is no need for an "alternative ideas" page; that page already exists, talks about the ultimate fate of the universe in general, and links to this one along with several other ideas. It is just depressing to see one side of any issue represented in the public domain, whether I agree with it or not. —Preceding unsigned comment added by 173.26.187.160 (talk) 20:42, 14 January 2010 (UTC)

What about electrons?

You cover protons and neutrons, but there's no mention of electrons. What happens to them?

Latrosicarius 16:17, 19 July 2007 (UTC)

I think electrons stay as electrons, since they are elementary and do not decay. The article does mention that leptons remain, and electrons are leptons.Eebster the Great (talk) 17:10, 27 March 2008 (UTC)

Alternatives to Hawking Radiation?

Hawking radiation is not proven. Can you write a section on the conflicts of this theory if black holes actually don't evaporate? Regardless of your opinions of whether Hawking is right or wrong, this issue should not be snubbed, ignored, or disregarded.

Latrosicarius 16:17, 19 July 2007 (UTC)

If black holes do not decay, the theory would end up with all matter as leptons, bosons, or black holes, rather than simply as leptons or bosons. However, if Hawking radiation is false, the Universe will never truly achieve a heat death since black holes represent maximum entropy and in an accelerating universe not all matter can ever be captured in a black hole. Keep in mind, I'm no physicist, but that's how I understand it. Somebody with a better understanding perhaps should write this section. Keep in mind also, though, that this is just one possible theory, and odds are very, very strongly against protons decaying at all.Eebster the Great (talk) 17:13, 27 March 2008 (UTC)

Decay into quarks?

In this article protons decay directly into radiation.

Originally, I thought protons would decay via beta decay into 1 free neutron, 1 positron, and 1 neutrino, except this couldn't be the case because it requires energy be input into the equation.

So how, exactly, would they decay? Would just degenerate into free quarks?

On the proton decay page page, it says:

According to some such theories, the proton would have a half-life of 10^36 years, and would decay into a positron and a neutral pion that itself immediately decays into photons in the range of gamma radiation:

Why, exactly do they think that? Why do they say it's a pion and not a full neutron? Where's the neutrino? Can this be explained further?

Latrosicarius 16:17, 19 July 2007 (UTC)

Alternatives to Singularities?

It is not proven that black holes are ring singularities. The article states that black holes are the only place immune to proton decay. However, if theories are true where there's an actual oblate spheroid of degenerate matter inside a black hole's event horizon, then that matter (which would theoretically be composed of neutrons or quarks) would indeed be under the influence of decay. Again, regardless on your opinions of whether Karl Schwarzschild's solutions to Einstein's Field Equations are correct or incorrect, this is still an important alternative which should not be disregarded.

Latrosicarius 16:17, 19 July 2007 (UTC)

Re your questions:

Electrons. Since no charged particle lighter than the electron is known, and since, assuming that charge is conserved, the decay products of an electron would have to contain at least one charged particle, the electron is presumed to be stable.

Proton decay. A decay channel allowed by some grand unified theories is the reaction (quark, quark) → (antiquark, antilepton). See e.g. Proton decay in terms of an effective baryon-lepton transition, W. Lucha and H. Stremnitzer, Zeitschrift für Physik C 17, #3 (September 1983), pp. 229–242. This immediately gives the reaction p → π⁰ + e⁺.

Protons decaying inside a black hole. Whether it happens or not is irrelevant to events outside the black hole as the decay products cannot escape the hole. Spacepotato 01:30, 7 August 2007 (UTC)

The name

I'm not so sure about despite its name. Heat death to me has always meant the death (nonexistance) of heat, rather than death through overheating. But maybe this is because I don't remember being confused when i first heard the term? Morwen 20:46, 10 Nov 2003 (UTC)

Hmm, I think alot of people will disagree with the idea thatan a universe that contiunes to expand will approach heat death asymptotically.

The first line of disagreement I can see is that although the 19th century scientist who came up with the idea of the heat death of the universe meant it to refer to the maximal entropy state of the universe, he was talking about a steady state model. However heat death conventionally means total thermal equilibrium (which is obviously the same as a maximal entropy state in what we'd normally think of a s a closed system) and I see no reason why an expandingf universe cannot be in thermal equilibrium before it reaches it's maximal entropy state. I'm pretty certain that in general the 'heat death of the universe' is used to describe a state that will occur after a finite period of time (i.e. the usuage I've detailed above) rather than that detailed in the article.

Secondly even if we do take heat death as equivalent to maximal entropy, does it approach really maximal entropy asymptotically? I can see why it would approach in a declerating infinitely expanding model, but I don't see why it should in one with linear or accelerating expansion. I can't say I'm 100% sure about this but in the latter two models what stops them from having arbitarily high entropies?

I think these two points do need to be clarified in the finished article. — Preceding unsigned comment added by 81.86.176.221 (talk) 22:47, 22 May 2004 (UTC)

Heat-death vs Big Freeze

As far as I can understand (and as suggested here), heat death means a flat universe dying from max entropy, and the Big Freeze is an open (constantly expanding) universe dying from expansion causing heat to be spread out - the effects are the same, but the causes different. I've updated the article a little accordingly and linked to that page, but it would be useful if someone could check that this is correct and if so explain it a bit more clearly than I've done :) --Jomel 16:17, 13 Aug 2004 (UTC)

There defintely needs to be more clarification here. As far as I, an amateur, can perceive, the only difference is that "heat death" involves an exhaustion of all entropy whereas "big freeze" involves matter being so spread out that any residual energy is nearly useless. BOTH of these articles need a "compare & contrast" section or else I'd say that an overzealous editor may ask for them to be merged. (Which I don't feel that they should be.) Again, without it being spelled out, it's somewhat difficult to differentiate the two items. JD79 17:47, 1 June 2006 (UTC)

Helmholtz or Clausius

Does anyone please remember who originated the concept?

Acc to: http://webplaza.pt.lu/fklaess/html/HISTORIA.HTML

it was helmholtz in 1854

interestingly, Clausius is listed LATER with the second law in 1865 .. {{subst:unsignedip}}

Admittedly, there are a few references on the web to this (only a few!) but can anyone actuall give a citation of where Helmholtz actually said this? Cutler 11:41, July 13, 2005 (UTC)

It was neither; William Thomson was the one. I rewrote the history section to show this, with references. --Sadi Carnot 20:26, 28 June 2007 (UTC)

Third law of Thermodynamics

Doesn't the third law of thermodynamics play a role here, too? As in, assuming an expanding universe, the temperature will decrease to approximately zero - hence the entropy will go to zero, which I guess actually avoids the whole Heat Death at the end, ultimately going towards the Big Freeze. Or is there a way in which the temperature stays at a non-zero value? (I guess this would be possible with a critically flat universe.) Mike Peel 21:56, 15 March 2006 (UTC)

It is my understanding that the temperature will not reach zero because heat is the "basest" form of energy and since energy can neither be created nor destroyed (more or less) then there will always be heat. There will just be a lack of any type of mechanism to change heat into anything else, and everything will be the same temperature. JD79 17:50, 1 June 2006 (UTC)

Though, that temperature would be the limit of e/x, where x is... whatever you want it to be, but something that would give you something like "heat density", as x (essentially the size of the universe) goes to infinity, and e is the 'total' amount of energy that exists. e's exact value doesn't matter, by definition, the limit is 0. So, the average energy is, effectively, 0.... --67.233.205.187 (talk) 03:28, 16 March 2008 (UTC)

Fate of the Black Holes is wrong

Black holes will only boil away if their temperature is greater than the temperature of the background radiation. Otherwise they will continue to absorb more energy from the background radiation than they give up through Hawking radiation. At the moment (temp = 2.73 K), the tipping point is for a black hole to have approximately the mass of the planet Mercury.

The scenario in the article at the moment appears to be based on the Big Freeze scenario, with the CMB temperature continuing to fall as the universe continues to expand.

But what happens with the Heat Death scenario? Any little black holes presumably boil away. But bigger black holes continue to grow, taking energy from the CMB, which makes it cooler. This may make more of the black holes too small to survive. Eventually, presumably, only the biggest coldest black hole of the lot survives, in thermal equilibrium with the CMB.

At least that's how it would seem to me to have to go. Jheald 13:10, 6 July 2006 (UTC).

I'm sorry, but what are you talking about?? The biggest, coldest black hole? Black holes are billions or trillions of degrees C. Also black holes wouldn't be taking energy from Cosmic Background Radiation... if anything, they'd be disbursing energy into the CBR. And you make it seem like black holes boiling away is somehow another way, besides hawking radiation for them to lose mass. (!) Uh no...

Also, I think you're confused about the Heat Death / Big Freeze issue. The article is talking about Heat Death (as in, the death of heat). It's due to maximum entropy. The Big Freeze is only talking about the universe expanding so much, all the matter is spread way out. There's still matter in the Big Freeze theory. In the Heat Death theory, all matter decomposes into energy.

Latrosicarius 17:15, 19 July 2007 (UTC)

Latrosicarius, you jumped to that conclusion way too fast. Yes, most black holes have enormous temperatures, but over long periods of time absorbing only background radiation they would cool until they reached thermal equilibrium with the background radiation. Black holes WOULD disburse energy via Hawking radiation, and also absorb energy from getting hit by the rays, obviously. The idea is that when the rate of radiation reaches equilibrium with the rate of absorbtion, the black hole would stop "boiling away", and would remain at a constant size and temperature. You also seem to think you know far more on this than he, but you posted several questions already, and, in fact, made mistakes just in that post alone. No, NOT all matter decomposes into energy in heat death, only all baryonic matter--leptons and photons still exist (I assume by energy you mean photons, but leptons are certainly matter by any ordinary definition; other energy might exist as gravitons, Higgs bosons, and virtual particles). Electrons and all 3 neutrinos are stable.Eebster the Great (talk) 18:49, 27 March 2008 (UTC)

I copied the detailed walkthrough of the scenario from an old verion of Timeline of the Universe, which was later merged into Timeline of the Big Bang, to the exclusion of this material. The relevant version, which was the last major one before the merge, is at http://en.wikipedia.org/w/index.php?title=Timeline_of_the_Universe&oldid=28769719

I don't actually have a lot of familiarity with the topic myself. At least, not enough to spot and correct technical errors. If you've got some relevant sources, by all means, go ahead and make the edit. The information here is well over a year old now, and even if it was correct at the time it wouldn't be surprising if this is now outdated. Arturus 03:45, 7 July 2006 (UTC)

I'd prefer to leave any final change to someone who's more of an expert. I just think what's in the article at the moment is not correct, if we're not talking about the Big Freeze. Jheald 17:51, 7 July 2006 (UTC).

Ultimate fate

"even smallest perturbations make the biggest difference in this era"

I suspect that this is poorly worded and should say something more like ""even small perturbations make a big difference in this era". {{subst:unsignedip}}

I agree with you, and I don't really understand the premise here anyways. Why should microscopic perturbations make a bigger different in the photon era than they do now?Eebster the Great (talk) 01:14, 8 May 2008 (UTC)

I'm a pretty big amateur at this, but it's my understanding that this is a function of approaching maximum entropy. Because the universe is so stable, the smallest events will reverberate across impossibly large scales. Think of it as the difference between throwing a rock into the ocean during a turbulent storm or into a calm pond. In the former, the splash of the rock will almost immediately be destroyed by the crashing waves. In the latter, the ripples will continue much further as there is nothing to get in their way. It still seems like a very difficult concept to comprehend and I would like to see more references and a further fleshing out of the theories. --JD79 (talk) 02:26, 13 May 2008 (UTC)

The analogy is good, but not strictly correct. If you toss a rock into the ocean during the storm, the size of the waves produced is not a function of the storm. Wave motion in water is an approximately linear system, so they still exist and propagate. It's just relative to the large waves they are nigh impossible to measure. I assume it's the same in a universe in thermal equilibrium.-Andy 64.217.216.119 (talk) 16:32, 26 January 2010 (UTC)

Question

How does this theroy explain the whole "energy can not be created or destroyed" law. If the universe is going to be nothing but photons, etc, in what form will all of the energy be in? --Cngodles 16:03, 6 March 2007 (UTC)

Energy is defined as the ability to do work. I think that the form of energy for a photon would be related to its wavelength. --Comosabi 17:53, 30 March 2007 (UTC)

Photons do indeed have energy, and this would be where most of the energy of the universe would be at heat death (unless some mechanism converts a lot of mass to neutrinos or what-have-you instead of photons). Entropy doesn't change the amount of energy present; instead, it's a measure of how much energy is "unavailable" (i.e., can't be tapped to do further work). A universe experiencing heat death could be described as being at maximum entropy, but an equally valid description is to say that all of its energy is unavailable (heat, but no heat gradients to tap for power, and so forth). --Christopher Thomas 04:08, 31 March 2007 (UTC)

Role of Dark Energy and Dark Matter

Keep in mind that ordinary matter accounts for less than 5% of the matter in the universe, while the rest is comprised of Dark Matter, ~20%, and Dark Energy, ~75%. While Dark Matter is not known to contribute to the expansion of the universe, Dark Energy does cause the universe to expand, since Dark Energy repels itself. The understanding of Dark Energy is still in its infancy, but any discussion of the Heat Death theory requires the inclusion of Dark Energy and Dark Matter. Comosabi 17:49, 30 March 2007 (UTC)

I've updated the relevant section to make it clearer, and to remove the flagged weaselling (or at least, to clarify where it comes from). As far as the question of whether the universe is open or closed is concerned, dark matter and normal matter are equivalent (only the total mass density of the universe matters). Dark matter may affect the final form in which matter exists in a universe that experiences heat death (in particular, if it's the most stable form of matter, normal matter may be converted to it by some mechanism). However, the best guess is that all normal matter decays into photons (via being absorbed into black holes that later evaporate), and that dark matter is either processed in the same manner (if it has enough self-scattering to diffuse into one or enough time to tunnel into one), or stays dark matter (decaying to the most stable dark matter particle, if it isn't already in that state).

Dark energy, on the other hand, causes the universe to expand in an accelerating manner. Dark energy that behaves in a manner similar to the cosmological constant, which is the simplest assumption, just perturbs the final state of the universe a bit (it's still a Big Freeze, but the universe doesn't quite reach heat death). Dark energy with the properties needed to produce a Big Rip scenario gives you a very different situation, but I'm not sure how entropy is affected under those conditions. My impression is that you end up with an arbitrarily large amount of usable energy, and so low entropy, but I could easily be wrong about that. One of the lurking physics-types may be able to give a better answer. --Christopher Thomas 04:42, 31 March 2007 (UTC)

Tweaks to "current status"

I've partly rewritten the "current status" section to avoid weaselling. To the best of my knowledge, it reflects the current beliefs about the probable fate of the universe, and for completeness it touches on noteworthy past conjectures (while making clear which ones are current). Two things are needed: The crew from Wikipedia:WikiProject Physics or a similar crowd needs to check it for accuracy, and all of the statements marked with "citation needed" templates need to get properly referenced. These references certainly exist; I just don't know them off the top of my head (whereas physics and cosmology types might). --Christopher Thomas 04:52, 31 March 2007 (UTC)

Compared to Big Rip or Big Freeze, is this theory considered to be the most likely to occur?

^Topic 64.236.245.243 14:57, 14 June 2007 (UTC)

That is an interesting question, though I do not see it as something of great importance in this article, which is about how a heat death would occur. But to be honest, scientists cannot really be sure. However, one problem for the heat death scenario is that the universe is an open system due to its expansion. This might pose a problem for entropy ever approaching maximum. Another possible scenario is that the universe runs out of hydrogen and all stars die. As for what happens next, that is outside my knowledge. Overall, there is so much we do not know about the universe, so many varying factors, and so many possibilities that there is no scientific consensus (as far as I know) on the final fate of the universe. 68.175.106.168 05:06, 13 October 2007 (UTC)

Heat death of this type is considered unlikely, as no experiments have ever discovered the decay of a single proton, and the theory which requires proton decay suffers from numerous other problems. I can't calculate odds or anything, but this appears to be much less likely than the big freeze or big rip, but probably more likely than the big crunch, which would require a massive, inexplicable, and not usually theoretically accepted cosmic collapse, also against experimental data. However, if protons are stable, a big freeze-esque scenario can still be considered a heat death, since all matter as protons, electrons, neutrinos, and photons would have the highest entropy. Hopefully the Large Hadron Collider will give further insight into this area.Eebster the Great (talk) 19:00, 27 March 2008 (UTC)

Unfortunately, that could take some time. Seems a little something broke on the LHC. I thought that since heat death was simply maximum entropy of the universe resulting in a rather boring universe with very little activity, proton decay isn't necessarily required. But here's the good news for those who find the idea of a heat death depressing: Quantum Mechanics. They could become quite significant over a very long period of time in a heat death afflicted universe and in the end, the effects would be somewhat interesting. I've even heard, though this seems a bit of a stretch, that hypothetically, the universe could end up in a heat death at some point in the somewhat (relative to the total lifetime of forever) near future only to end up back in the state it was in five nanoseconds after I hit the enter button on my keyboard. 68.175.105.134 (talk) 03:23, 22 September 2008 (UTC)

Eh?

"The probability of all things approaches a maximum of 1 in this age. (i.e. a school bus randomly appears out of the nothingness) All comprehensible laws of reality cease to exist. A surrealist universe begins."

What? {{subst:unsignedip}}

I was about to comment on that same passage. I'm far from having even an average understanding of physics, but doesn't "maximum enthropy" mean that there is not usable energy left in the universe? And if all matter has decayed, down to even the proton itself, there's nothing to hold information about what a "school bus" is or looks like, right? So one couldn't possibly "randomly appear out of the nothingness". And certainly life couldn't appear in such a universe, so the probability of "all things" would certainly not be "1".190.73.98.191 15:00, 5 July 2007 (UTC)

I removed it; it's not only wholly illogical on its face (from nothing, nothing comes) but also vandalism wrapped up in pretty words. 75.66.172.38 19:37, 5 July 2007 (UTC)

Possible Flaws Section

I've deleted the section until someone busts out some sources, or said section makes some degree of logical sense. — Preceding unsigned comment added by 75.66.172.38 (talk) 19:38, 5 July 2007 (UTC)

Contents

Did anyone notice that the powers in the content box aren't displayed correctly and look like they're part of their bases (eg. 1014 years)? —The preceding unsigned comment was added by 213.222.167.61 (talk) 23:35, August 22, 2007 (UTC)

Image captions

We don't need poetic captions in an encyclopedia. -- 195.195.166.31 (talk) 14:21, 1 March 2008 (UTC)

+1 User:Krator (t c) 21:38, 17 March 2008 (UTC)

Neutrinos

Neutrinos do not decay, nor interact with photons, therefore they will be remaining after all other matter has been lost. —Preceding unsigned comment added by 144.173.6.75 (talk) 16:04, 13 March 2008 (UTC)

And as such, the article mentions that leptons will persist for a very long time if not until the end of the universe. The only reason they perhaps would not exist to the very end would be if all the leptons in the universe were swallowed by black holes before those black holes faded away. I don't see there being an adequate reason all leptons would be thus swallowed, though, so I imagine some neutrinos and electrons would indeed exist at the end of the universe. Eebster the Great (talk) 01:08, 8 May 2008 (UTC)

Planets fall or are flung from orbits: 10^15 years, stars by 10^16 years

Is there a source for this? Serendi^podous 10:42, 2 April 2008 (UTC)

This entire article assumes proton decay

I think something has to be done about the fact that this entire article assumes proton decay to be true, despite a complete lack of evidence that proton decay even exists. Most of the article assumes proton decay as automatically true. That makes most of this article speculative. Seems to be a problem for a Wikipedia article, based on what I know. Any thoughts? SkepticBanner (talk) 02:28, 19 April 2008 (UTC)

I noticed that too. "If estimates of the half-life of protons are correct," then the article makes sense, but it has to clear up the fact that there isn't any evidence that protons decay. Besides, the article seems to assume the lower bound for proton half-life (if it were shorter we would have observed proton decay), without providing a good reason for doing so. Eebster the Great (talk) 01:02, 8 May 2008 (UTC)

Mostly unrelated, but in the same paragraph, is the statement "Effectively, all matter would be contained within black holes, which are immune to proton decay, and leptons". Why are black holes immune to proton decay? I can't find anything in the black hole article either --JD79 (talk) 02:23, 13 May 2008 (UTC)

What if it's final?

What if the heat death is final, and nothing wlll ever change after that? JIP | Talk 19:40, 20 May 2008 (UTC)

Heat Death is supposed to be final. That's what death means. But particles will still exist on the Quantum level if it makes you feel any better. So there may always be some Quarks and Leptons to form into something. They'll have an infinite amount of time after all. That could be how this Universe was created in the first place.76.31.64.54 (talk) 14:43, 29 May 2008 (UTC)

No, they couldn't. otherwise it's not Heat Death. As you said heat death means it's final. Science isn't about making people feel better, it's about the fact's. Chocolog (talk) 14:04, 9 September 2009 (UTC)

The Beginning of the Degenerate Age at 10^15 years.

I noticed that this article states a date of 10^14 (100 trillion) years as the start of the Degenerate Age but other wikipedia articles such as "Graphical timeline of the Stelliferous Era" mention a date of 10^15 (One Quadrillion) Years. I have found a source that also states 10^15 years as the beginning of the Degenerate Age. I hope it helps. Please tell me which date is correct 10^14 or 10^15 because both Wikipedia articles state different dates which is quite significant since they differ by about 900 trillion years. Thank You.

http://everything2.com/index.pl?node_id=1014847 Maldek (talk) 02:58, 20 June 2008 (UTC)

I think 14 is an error. There are two Wikipedia articles that says 15: The Five Ages of the Universe and Cosmological decade.

And the Stelliferous Era probably starts at 10^6 years, despite there were no stars shining at that time. Najro (talk) 17:59, 16 July 2008 (UTC)

They are called Era's not Ages

I have noticed that in this article time periods are discussed such as Degenerate Age, Black Hole Age, Dark Age, and Photon Age. I have noticed that on the bottom of this article they are listed as Era's not ages. So it is called Degenerate Era, Black Hole Era, Dark Era, Photon Era etc. In all of the other Wikipedia articles these time periods are called Era's not Ages. Even searching Degenerate Age on the internet brings up nothing but searching Degenerate Era brings up many Wikipedia articles and other useful information. Even on the bottom of this article the time periods are referred to as Era's. Is it okay if I change them to Era's? Thank You.Maldek (talk) 04:59, 20 June 2008 (UTC)

Stars burn out 10^14 years. Planets deattach from stars 10^15 years. Stars deattatch from Galaxies 10^16 years?

If Stars will burn out in 10^14 years then why does it say that planets will be deattached from their orbits in 10^15 years and Stars will be deattached from their orbits in 10^16 years. Could you please clarify this for me. Thank You.Maldek (talk) 02:44, 21 June 2008 (UTC)

Official Large number Page

Here is the official source for the large numbers I use in this page

http://www.polytope.net/hedrondude/illion.htm

Hope you enjoy. Thank You.Maldek (talk) 04:57, 27 June 2008 (UTC)

All these weird names is making the page look bizarre. The site you mention even states "those above millillion are names I invented" (heck and we don't even know who the "I" is). That site fails to match any remote idea of WP:RS and is self-published.Ttiotsw (talk) 08:47, 27 June 2008 (UTC)

There is no official source for the names of numbers above a vigintillion (10⁶³ short scale, 10¹²⁰ long scale) or thereabouts. Spacepotato (talk) 22:38, 27 June 2008 (UTC)

Bizarre *illion names versus Exponential Notation.

Exponential Notation (e.g. 1 x 10¹⁶ ) is a much better way of representing large numbers than the bizarre *illion names. Why ?,

• the various *illion names are not easily translatable,
• Exponential notations are easily comparable (add/subtract, multiple/divide),
• no reliable definitions for all powers of 10,
• recentism for many names. _{(Note: fix spelling as did say "may names")}

I suggest that all *illion names are removed from this article and any other article like this for far-in-the-future dates unless there is a reliable sources that uses that name for that time period (e.g. a scientist uses "Unvigintillion" on a regular basis rather than 10⁶⁶ ) Ttiotsw (talk) 08:55, 27 June 2008 (UTC)

Maybe not the best thing to turn this article into a number exercise like Names of large numbers. Why not remove the number names from the headings as it was before? For the most important events the number names could be used, in the text only. Najro (talk) 19:54, 27 June 2008 (UTC)

Or keep some number names in the headings but reduce the use of them to much less than now. Najro (talk) 20:11, 27 June 2008 (UTC)

I agree. Many of these large numbers have no generally accepted names. Even for those which do, the names are not generally used, and understanding the size of the numbers is easier when they are expressed in exponential notation. I am removing most of the names from the article. Spacepotato (talk) 22:35, 27 June 2008 (UTC)

We should never use those names at all for the reasons I've given above plus who is the authority to call that date that name ?. Now if some scientist keeps using one of the names and it becomes part of culture then we could use it else we're just promoting a fringe view of that number. Ttiotsw (talk) 06:14, 28 June 2008 (UTC)

Okay just got the message and was asked to justify the use of large number names. Thank you very much for notifying me. First of all you may be right that using exponents is a better way of representing relativiely large numbers. The point is I am still keeping the exponents in there so that everyone can easily refer to it but in addition I am giving scientific names in addition. Numbers up to 10^3003 (One Millillion) are commonly used. Above One Millillion are names of numbers that are not commonly used as you may have seen in the source I gave you. Up to a Millillion (10^3003) you will find everywhere but numbers above that can still be found in many places but they may not be listed in encyclopedias. The point is I am not taking away the exponets and I am not listing any names of numbers above 10^3003, heck not even close to 10^3003. I just felt I should add something to it. Another thing is that I think exponents do confuse people. The thing is that before I started editing this article I was confused because of so many inconsistencies within the article. As you can see I have added many questions on the discussion page in an attempt to understand these apparent inconsistencies. After a while none of my questions were answered so I did extensive research on the subject matter to find out the truth. After a few weeks I got the answers to my questions. I have already discussed all of the changes on the talk page but for those weeks nobody was interested in this article or what I had to say, so I took it upon myself to improve this article. As I just mentioned I have notifed this on the discussion page. I do understand that there are no quotes in the article supplied by me, but that is because I do not know how to put quotes in the article. I mean I know how to do it, but I don’t know how to do it without it appearing in the article, you know like how to do foot note style. Anyways in my original edits whenever I used a new piece of information I wrote down the URL of the website in the edit summary on the bottom of every Wikipedia summary. I would really appreciate it if I could find out how to do footnotes, but you can always look at the source found it my edits that I included when I first supplied new information. Another thing you might be interested in knowing is that I also had to change lot of the content of the articles because I understand Wikipedia does not tolerate plagiarism. The sad thing is that plagiarism of this article and 1 E19 s and more have both been plagiarized. Before I started editing these two articles both of them were exact copies of articles on the internet. I had to change them so they that they were not plagiarized. Here are the URL’s of the two plagiarized articles. This is the original article plagiarized by the Wikipedia article Heat death of the Universe http://www.tripatlas.com/Heat_death_of_the_universe

You should look at this site and compare this article with this Wikipedia article before I ever started editing this article. What you will notice is that it is exactly same word for word. Even the pictures are all the same, except for one picture of an asteroid that was taken off a couple months ago. But if you go back even further you will see that the asteroid was also originally there in this article. As you can see this source is not even listed as a source even though it was copied word for word. In fact it was never listed word for word and this deceit has been going on for many years. The fact that this Wikipedia article is plagiarized and had many inconsistencies is why I had to change it. I do not know how to do footnotes but I will post all of my sources on the discussion page and explain my edits. Thank you for informing me and just in case you are interested I will show you the article that 1 E19 s and more plagiarized. It is listed below. http://www.openencyclopedia.net/index.php/1_E19_s_and_more

I stumbled upon these two articles while I was extensively researching in search of the truth. Thank you once again and if you have any questions please ask. Maldek (talk) 18:45, 28 June 2008 (UTC)

Retrieved from "http://en.wikipedia.org/wiki/Talk:Heat_death_of_the_universe"

1. Your statement that names of numbers up to 10^3003 are commonly used is not correct. It is true that people have devised names for some of these numbers, which you can find in various books and websites, but these names are not commonly used. For example, if you search for the word trevigintillion on Google Books or Google Scholar, you will find no occurrences.
2. The first source, http://www.tripatlas.com/Heat_death_of_the_universe , which you claim this article was plagiarized from is a mirror of Wikipedia. To quote from the bottom of the page: "This article provided by Wikipedia". They copied us, not we them.
3. The other source, http://www.openencyclopedia.net/index.php/1_E19_s_and_more , which you claim the >10¹⁹ seconds article was plagiarized from is also a mirror of Wikipedia. To quote from http://openencyclopedia.net/index.php/Main_Page : "As of right now this site is nothing more than a mirror of the Wikipedia Database. So feel free to use the site if wikipedia is running a little slow. The wikipedia database was last updated 7 February 2006."
4. Your statement that you always provided sources in your edit summaries is not correct. For example, in this edit you use the summary: "Added the end of all stars from another Wikipedia article and a scholary journal". This is of no value as a reference as it doesn't tell us where your information is coming from.
5. It's best to provide inline footnotes for your sources. To do this, you should add the template {{reflist}} to the end of the article. Then, whenever you want to insert a footnote, use the <ref> and </ref> tags to surround the footnote text. For example, if you wanted to say that 2+2=4 and credit this fact to the January 3, 2005 issue of Science, p. 183, write: 2+2=4<ref>p. 183, ''Science'', January 3, 2005.</ref>.

Spacepotato (talk) 01:14, 29 June 2008 (UTC)

Justification of Large Number Names

Okay just got the message and was asked to justify the use of large number names. Thank you very much for notifying me. First of all you may be right that using exponents is a better way of representing relativiely large numbers. The point is I am still keeping the exponents in there so that everyone can easily refer to it but in addition I am giving scientific names in addition. Numbers up to 10^3003 (One Millillion) are commonly used. Above One Millillion are names of numbers that are not commonly used as you may have seen in the source I gave you. Up to a Millillion (10^3003) you will find everywhere but numbers above that can still be found in many places but they may not be listed in encyclopedias. The point is I am not taking away the exponets and I am not listing any names of numbers above 10^3003, heck not even close to 10^3003. I just felt I should add something to it. Another thing is that I think exponents do confuse people. The thing is that before I started editing this article I was confused because of so many inconsistencies within the article. As you can see I have added many questions on the discussion page in an attempt to understand these apparent inconsistencies. After a while none of my questions were answered so I did extensive research on the subject matter to find out the truth. After a few weeks I got the answers to my questions. I have already discussed all of the changes on the talk page but for those weeks nobody was interested in this article or what I had to say, so I took it upon myself to improve this article. As I just mentioned I have notifed this on the discussion page. I do understand that there are no quotes in the article supplied by me, but that is because I do not know how to put quotes in the article. I mean I know how to do it, but I don’t know how to do it without it appearing in the article, you know like how to do foot note style. Anyways in my original edits whenever I used a new piece of information I wrote down the URL of the website in the edit summary on the bottom of every Wikipedia summary. I would really appreciate it if I could find out how to do footnotes, but you can always look at the source found it my edits that I included when I first supplied new information. Another thing you might be interested in knowing is that I also had to change lot of the content of the articles because I understand Wikipedia does not tolerate plagiarism. The sad thing is that plagiarism of this article and 1 E19 s and more have both been plagiarized. Before I started editing these two articles both of them were exact copies of articles on the internet. I had to change them so they that they were not plagiarized. Here are the URL’s of the two plagiarized articles. This is the original article plagiarized by the Wikipedia article Heat death of the Universe http://www.tripatlas.com/Heat_death_of_the_universe

You should look at this site and compare this article with this Wikipedia article before I ever started editing this article. What you will notice is that it is exactly same word for word. Even the pictures are all the same, except for one picture of an asteroid that was taken off a couple months ago. But if you go back even further you will see that the asteroid was also originally there in this article. As you can see this source is not even listed as a source even though it was copied word for word. In fact it was never listed word for word and this deceit has been going on for many years. The fact that this Wikipedia article is plagiarized and had many inconsistencies is why I had to change it. I do not know how to do footnotes but I will post all of my sources on the discussion page and explain my edits. Thank you for informing me and just in case you are interested I will show you the article that 1 E19 s and more plagiarized. It is listed below. http://www.openencyclopedia.net/index.php/1_E19_s_and_more

I stumbled upon these two articles while I was extensively researching in search of the truth. Thank you once again and if you have any questions please ask. Maldek (talk) 18:45, 28 June 2008 (UTC)

As described elsewhere you are WRONG. Do not use any names of large numbers. They are fringe. Ttiotsw (talk) 04:30, 4 July 2008 (UTC)

My Sources for Heat death of the universe

Here my sources. As I said I am not sure how to put references on the page so I will list them here on the discussion for everyone to easily see. I hope there are enough sources. I have researched extensively for the truth. Please feel free to ask questions. Thank You once again for your patience and cooperation.

Stellar Formation Ceases in 100 trillion years

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

All Stars gone in 200 trillion years

http://emptv.com/print/334

http://emptv.com/in/science

Red Dwarfs can live for more than 100 trillion years.

http://filer.case.edu/sjr16/stars_lifedeath.html

http://filer.case.edu/~sjr16/advanced/stars_avgdeath.html

The orbits of planets will decay due to gravitational radiation in One quadrillion years.

http://emptv.com/print/334

http://emptv.com/in/science

The Orbits of White Dwarfs and Black Dwarfs will decay due to gravitational radiation in One Quintillion years.

http://emptv.com/print/334

http://emptv.com/in/science

Light can exist in the Universe after all stars are gone if two white dwarfs with a combined mass of more than about 1.4 solar masses happen to merge, the resulting object undergoes runaway thermonuclear fusion. The result is a Type Ia supernova. Very, very rarely, the darkness of the Degenerate Age is dispelled for a few weeks while a supernova explodes.

http://spiff.rit.edu/classes/phys240/lectures/future/future.html

Protons decay in 10^40 years

http://www.everything2.com/title/radioactive

http://www.museumofhoaxes.com/hoax/weblog/comments/2530/P20/

http://www.physicsforums.com/archive/index.php/t-1955.html

Timeline for when different size black holes evaporate

http://www.magicdragon.com/UltimateSF/timelineCF.html

Supermassive Black Holes Evaporate in 10^106

http://physics.gmu.edu/astr103/CourseNotes/Html/Lec09/Lec09_pt2_cosmologyModern.htm

Common Uses of Large Numbers

http://www.unc.edu/~rowlett/units/large.html

http://faqs.cs.uu.nl/na-dir/sci-math-faq/largenumbers.html

http://www.jimloy.com/math/billion.htm

http://www.sizes.com/numbers/big_numName.htm

http://hometown.aol.com/hedrondude/scrapers.html

http://isthe.com/cgi-bin/number.cgi

http://en.encyclopedia.livepress.com/index.php/Zettillion

http://www.mrob.com/pub/math/largenum-3.html

http://www.sci.wsu.edu/math/faculty/hudelson/moser.html

http://www.uni-bonn.de/~manfear/numbers_names.php

http://mathforum.org/library/drmath/view/59155.html

http://mathworld.wolfram.com/LargeNumber.html

http://www.sizes.com/numbers/big_numName.htm

http://www.polytope.net/hedrondude/home.htm

Maldek (talk) 19:56, 28 June 2008 (UTC)

OK, the first question is easy: why do you still spam talk pages with huge numbers of links ?. We don't care to discuss the topic but how to improve the article. For example,

• The EMPTV web site ? How is that any more than a blog ?
• The physicsbookstore.org at the bottom has links to "Mortgages" and "Credit cards" !. Come on, shouldn't that ring alarm bells ?
• We don't care how many web sites you come up with that refer to the bizarre names of large numbers - we don't doubt they exist, we just don't believe they are used commonly in any reliable text. They are Fringe with a capital 'F'.

Please look at how other people use the talk pages and reference sources. It just isn't nice to blast a ton of links into the talk page.

In the end we don't even know what you want to say in the article. Edit the article, with your best reference (not just to a zillion blogs). If it gets reverted then argue the case. If consensus isn't what you want then let it go. Ttiotsw (talk) 09:19, 29 June 2008 (UTC)

1. Many of these sources are not particularly reliable. The emptv.com links, for example, are only someone's personal website (he seems to have gotten some of his information from us), and http://www.physicsforums.com/archive/index.php/t-1955.html and http://www.museumofhoaxes.com/hoax/weblog/comments/2530/P20/ are discussion forums. The lecture notes in http://spiff.rit.edu/classes/phys240/lectures/future/future.html are a reasonable source, but they are based on the more detailed treatment in Reviews of Modern Physics 69, 337–372 (Bibcode:1997RvMP...69..337A), so I would recommend looking at this paper.
2. Re the possibility of red dwarfs having a lifetime of over 10¹⁴ years, it is difficult to find solid estimates for the lifetimes of low-mass red dwarfs in the literature. Since these stars live for so long, it's not yet possible for us to observe most parts of their aging process, and so, until recently, astronomers have not bothered to study the problem in detail, and one finds people quoting rough estimates of very long lifetimes. To quote from New Light on Dark Stars, I. Neill Reid and Suzanne L. Hawley, Berlin: Springer, 2005, ISBN 978-3-540-25124-8, §3.8, §3.7: "It is only in the last decade, however, that it has become possible to compute reliable models for very low-mass stars and brown dwarfs." And: "Low-mass stars have main sequence lifetimes that are orders of magnitude longer than the present age of the Universe (currently estimated as 12–14 Gyr.) Little consideration has been given to the later phases of evolution of these objects, perhaps because the prospects of observing an evolved M dwarf are slight...The final stages of their existence — perhaps the ultimate luminous phase of the Universe — have been examined by Laughlin et al. [L4], the only detailed study of its kind to date." So, I would recommend reading [L4] (The End of the Main Sequence, Gregory Laughlin, Peter Bodenheimer, and Fred C. Adams, Astrophysical Journal 482, pp. 420–432, June 10, 1997, Bibcode:1997ApJ...482..420L, doi:10.1086/304125.) It gives a lifetime of between 10¹³ and 2×10¹³ years for the lowest-mass red dwarf stars. There is also some discussion of this subject in the Rev. Mod. Phys. paper I mentioned above.

Spacepotato (talk) 18:40, 30 June 2008 (UTC)

I've removed the references to emptv.com in the article. I run emptv.com and wrote the cited post, and most of its sources are Wikipedia, so if you cite emptv.com there'll be a closed loop of sourcing. --Zantolak (talk) 10:47, 6 July 2008 (UTC)

Re: Recent edits to the article

1. The consensus at Bizarre *illion names versus Exponential Notation. is that large number names should not be used. To quote WP:MOSNUM#Large numbers: "Scientific notation is preferred in scientific contexts."
2. The table of black hole lifetimes belongs in the Black Hole Era section, as that is when the black holes in the table evaporate.
3. The symbol for the Sun is ☉ (U+2609), and not ʘ (U+0298), which is a bilabial click.
4. There is no Photon Era. The scheme of eras comes from Adams and Laughlin (Reviews of Modern Physics 69, 337–372 (Bibcode:1997RvMP...69..337A), or see their popular book The Five Ages of the Universe), but they only have five eras, ending with the Dark Era. Other authors do not appear to use this term for a late age of the Universe either, although it may refer to an early period (see Photon epoch.)
5. Long lists of links should not be inserted in the middle of the article.
6. emptv.com is not a reliable source. It's just someone's personal website.
7. Forums, chat rooms, and comment threads on blogs are also not reliable.
8. In this revision, sources are being used to support claims they do not make. For example, to support the claim that protons have a half-life of about 10³⁶ years, the source http://hypography.com/forums/archive/t-11700.html is used. This is not a reliable source (it's a forum thread), and in any case says that 10³⁶ years is a lower bound, not an estimate. There are three sources used to support the claim that protons will have undergone 10,000 half-lives by 10⁴⁰ years:

   (a) http://www.everything2.com/title/radioactive . This is not a reliable source (everything2 is just as unreliable as we are) and gives 10⁴⁰ years as an estimate for the half-life of the proton, not an estimate for 10,000 half-lives of the proton.

   (b) http://www.museumofhoaxes.com/hoax/weblog/comments/2530/P20/ . This is not a reliable source (it's a forum thread) and likewise gives 10⁴⁰ years as an estimate for the half-life of the proton, not an estimate for 10,000 half-lives of the proton.

   (c) http://www.physicsforums.com/archive/index.php/t-1955.html . This is not a reliable source (it's another forum thread) and mentions 10⁴⁰ years simply as a hypothetical example, not as an estimate, lower bound, or upper bound on anything.

9. As I have explained above, the most reliable current estimates for the lifetimes of low-mass red dwarfs give a figure of between 10¹³ and 2×10¹³ years, not 10¹⁴ years.

Spacepotato (talk) 07:15, 5 July 2008 (UTC)

Maldek, you're turning this page into a farce!

Will you please come to some sort of an agreement with Spacepotato, because your constant flood of reverts and edits are making this universally important page farcical! CrackDragon (talk) 00:04, 6 July 2008 (UTC)

My sources and what I edit

I still do not understand what is considered a large number. Is it a million? Does a million have to be wrote as 10^6? You say no illion names so should I erase all names of a million or higher on all Wikipedia articles? Another thing is that the Photon Era has been listed years before you ever came and all of this information has been here you can't just change it because you want to, but anyways if you want I could erase all number names of one million or larger on all Wikipedia articles. Just tell me if this is what you want, but don't get mad at me for it. You are not being clear as to what you say is a large number. Is it a million?Maldek (talk) 00:08, 6 July 2008 (UTC)

• Million, billion, trillion are fine. For higher numbers, exponential notation is the accepted scientific norm. The names you use are contentious, rarely used, and sound downright childish!! CrackDragon (talk) 00:22, 6 July 2008 (UTC)

1. Where names of numbers should and should not be used depends on the article and the context. If the number 1,300,000,000 represents the population of China, for example, it is perfectly reasonable to write it as 1.3 billion. On the other hand, if it represents the number of molecules in a (nearly empty) region of space, it may be more reasonable to write it as 1.3×10⁹. In this article, I think that it's not useful to use names of numbers equal to or above 10¹⁵.
2. Yes, the Photon Era has been mentioned in this page for a long time, but it's not in the sources the rest of this material comes from. So, given that we can't substantiate it, it has to be taken out.

Spacepotato (talk) 00:36, 6 July 2008 (UTC)

I seriously think you 2×10⁰ should sort out your differences and come to some agreement, rather than continually edit each others edits, turning this page into a battleground! Anyone who continually refuses to compromise, and thinks only their point of view is correct is either:-

1. A spoiled brat!!
2. Some type of Bond-esque villian bent on world domination because their parents didn't love them enough!!
3. Mentally ill!!

Cummon lads! You surely don't want to be stuck with one of those monikers?! CrackDragon (talk) 00:52, 6 July 2008 (UTC)

An error of philosophy?

From what we know of the evolution of the universe, it has expanded roughly in proportion with its age and has been filled with matter whose temperature has dropped inversely with time. If time is viewed logarithmically, rather than linearly, then the universe can be perceived always to have been about the same size and temperature and to have particles within it moving roughly the same speed, relative to the size of the universe and the speed of light, which also can be perceived as remaining constant relative to what ordinarily we would call very small increments of space and time near the Big Bang. By this definition I suppose the wavelength of red-shifted light remains about the same, and perhaps defining its change (and the size of the universe) to be constant would be even a better way to see things. Of course, taking this view means accepting that all the entities of ordinary chemistry - atoms and molecules - were once enormous, flimsy things.

It follows that instead of expecting the universe to die a "heat death", we should renormalize our expectations. For some inhabitant of 10^100 years rather than 10^10 years, perhaps a temperature of 3x10^-8 Kelvins would seem quite balmy and a period of 10^10 days would seem like a fair time to accomplish something.

Of course, in order for such a time to have inhabitants it must have interesting physics, but just as physicists at the Large Hadron Collider expect to find an endless succession of effective field theories to describe higher and higher energies, perhaps there are tiny, subtle forces, weaker than gravity, slower than the decay of the proton, which we simply cannot measure against a background of more powerful forces. Such an idea may offend the notion of simple physics carved on stone tablets by a terse god, but it is not out of keeping with the florid excesses of the Mandelbrot Set.

It seems hard to find sources fully expressing a perspective of this type, yet it seems implicit in many statements that are made. I'd appreciate if anyone can post some good references I could make use of here. Wnt (talk) 16:29, 6 July 2008 (UTC)

This perspective is not new and has been used by previous writers on this subject. See for example Time without end: Physics and biology in an open universe, Freeman Dyson, Rev. Mod. Phys. 51, 447 - 460 (1979), or The Five Ages of the Universe, Adams and Laughlin, Free Press, 2000. Spacepotato (talk) 18:04, 6 July 2008 (UTC)

Thanks!! I located a freely accessible copy of the first [1] and (like any Dyson text I've ever run across) is a splendid read; the second sounds like a much expanded version of the reference you pointed me at earlier [2] and should be quite interesting to look into. —Preceding unsigned comment added by Wnt (talk • contribs) 22:45, 6 July 2008 (UTC)

Re: Recent edits (2)

1. Not all matter is baryonic. There is also the possibility of axions, WIMPs, etc.
2. The source, Page, Physical Review D 13 (1976), pp. 198–206, gives 2×10⁶⁶ years, not 10⁶⁶ years, as the lifetime of a solar-mass black hole. (The exact figure given is 2.16×10⁶⁶ years.)
3. Protons in black holes are not immune to proton decay.
4. The half-life of the proton is not known.

   (a) 10³² years is a lower bound. That means that we know it's at least 10³² years.

   (b) 10⁴¹ years is an upper bound. It is based on the assumptions that the Big Bang was inflationary and that the same process that makes protons decay made baryons dominate over anti-baryons in the early Universe. So, if these things are true, it can't be any more than 10⁴¹ years.

   (c) 10³⁷ years is an assumption, made only for the sake of having a definite figure.

Spacepotato (talk) 18:14, 6 July 2008 (UTC)

My Recent Edits

1. First of all I edited 10^37 years as the half-life of protons. Is there any source that says this? And if the half-life can be anywhere between 10^32 years and 10^41 years why can't 10^36 work? We both agree that all protons outside of black holes decay in 10^40 years so is there anyway we can find a source that says how many half-lives protons must go before all the protons in the universe decay?

2. All matter outside of black holes decay in 10^40 years. Does baryonic mean matter outside of black holes? Because if it does we can use this word baryonic. But the thing is that all matter outside of black holes decays in 10^40 years and I am not sure if all baryonic matter means the same thing, please clarify.

3. To avoid confusion I usually say that in 10^40 years all protons outside of black holes decay. I say this because the protons inside black holes do not start decaying until 10^66 years. The protons in black holes do decay but not by 10^40 years. In 10^40 years all the protons outside of black holes decay but the protons in black holes do not start decaying until 10^66 years. That is why I do this to avoid confusion otherwise the information would contradict each other since there would still be protons left in black holes until 10^106 years when even the protons in the supermassive black holes decay.

4. Another thing is that according to my source on the timeline of decay of black holes the figure 2x 10^66 etc. is not used. If you see the sourece it just lists 10^66, 10^69, 10^72 etc. Here is the site I got my information from regarding the timeline of black hole disintigration. I hope you find it helpful.

http://www.magicdragon.com/UltimateSF/timelineCF.html

I hope you see where I am coming from and I hope we can work this out. Thank You for your cooperation.Maldek (talk) 22:40, 6 July 2008 (UTC)

1. The reason to use 10³⁷ years as the proton half-life is that it is the arbitrary assumption used by Adams and Laughlin, who are the source for the scheme of eras (Primordial, Stelliferous, Degenerate, Black Hole, and Dark) used in this article. See "A dying universe: the long-term fate and evolution of astrophysical objects", Fred C. Adams and Gregory Laughlin, Reviews of Modern Physics 69, #2 (April 1997), pp. 337–372, Bibcode:1997RvMP...69..337A, doi:10.1103/RevModPhys.69.337, §IVA, last line.
2. Baryonic means made up of baryons. Baryons are particles which, like protons and neutrons, are made up of three quarks. The word has nothing to do with being outside black holes. The 10⁴⁰ year figure does not apply to non-baryonic matter, either inside or outside of black holes.
3. 2×10⁶⁶ years is the time it takes a solar-mass black hole to decay. It has nothing to do with the time it takes protons inside the black hole to decay. Being inside a black hole should not affect the rate of proton decay.
4. The Phys. Rev. D article is more reliable than the source you mention above, so we should use the 2×10⁶⁶ year figure as the time it takes a solar-mass black hole to decay.

Spacepotato (talk) 07:42, 7 July 2008 (UTC)

My New Edits

Hi there are a few things regarding this article that I have questions about.

1. You add neutron decay along with proton decay. Is there any source for neutron decay? How about electron decay?

2. You say in 10^40 years all protons will decay. Are there any protons in black holes? So if protons don’t decay in black holes, what decays?

3. What is baryonic matter? When will matter decay?

4. What's wrong with my source for the timeline for the decay of black holes? My source is listed below and it lists slightly different numbers. http://www.magicdragon.com/UltimateSF/timelineCF.html

5. I found two more sources for the half-life of a proton being 10^36 years. Are these two sources okay?

http://www.openencyclopedia.net/index.php/1_E19_s_and_more

http://en.encyclopedia.livepress.com/index.php/1_E25_s

6. I found another source for the Photon Era, can we use it?

http://www.experiencefestival.com/timeline_of_the_big_bang_-_the_photon_age_-_from_10150_years_until_the_distant_future

7. The Site I used for Black Hole Decay mentions large numbers. Since they are used in the article to describe the time periods of black hole decay can I use the numbers? The large numbers are listed there and you said I could use a number if the source lists the number? Please let me know.

http://www.magicdragon.com/UltimateSF/timelineCF.html

Thank You for your time, effort, and cooperation.Maldek (talk) 01:49, 8 July 2008 (UTC)

You appear to be repeating a lot of questions that have been answered by Spacepotato above (particularly your question #3).

1. Please read and understand WP:Reliable sources. None of the sources you used that I've checked (including the sources you've put in the text of the article) are reliable. In practice, for an article like this, most reliable sources will be 1) articles in peer-reviewed academic journals or published books (best), or 2) press releases from research institutions (e. g. NASA) or universities, or published news media, which is almost always reporting on a press release related to an article in a peer-reviewed journal. It's very hard to assess the merits of your edits when you use so many personal web sites, blogs, and other unreliable sources—any meritous edits in there get quickly lost. Using Google to find any old web page that supports your preferred number is neither good research nor appropriate for Wikipedia.
2. Re black holes: As far as I understand, we don't really understand the physics inside black holes, and I don't think it actually matters very much. ASHill (talk | contribs) 02:43, 8 July 2008 (UTC)

2. Neutron decay: Free neutrons decay with a half-life of about 10 minutes. They are more stable when bound into nuclei, but it's thought that the same processes that make protons decay should also make bound neutrons decay, so the decay rate should be similar. See Adams and Laughlin 1997 (as above, [3]), §IVA.
   Electron decay: Since charge is conserved, when a particle decays, it must decay into a collection of particles with smaller total rest mass and the same total charge. The electron is the lightest charged particle known, so it's believed to be stable.
3. (a) For a non-rotating black hole, any matter inside the hole will fall towards the center and end up at the singularity at the center of the hole. Since we have no theory of gravity that will predict what will happen at this singularity, we don't know what is inside the black hole. Away from the singularity, though, the laws of physics are expected to be the same as they are here outside.
   (b) What decays is the black hole itself. It emits Hawking radiation from the surface of its event horizon, which causes it to slowly lose mass.
4. (a) I already explained what baryonic matter is above, but to put it another way, baryonic matter is the normal kind of matter that rocks, trees, cats, dogs, Alizée Jacotey, the Sun, and all the planets in the Solar System are made out of. Astrophysicists have observed that there seems to be a good deal of dark matter which has a gravitational effect, but can't be observed in any other way, and they think that some of this may be non-baryonic matter, made up of neutrinos or some unknown kind of elementary particle.
   (b) Baryonic matter will decay in a small number of proton half-lives.
5. The page you mention is mostly a bunch of quotes from different sources, along with commentary from the author of the page, arranged so that it's not always clear which is which and what source is being quoted. It's better to get your information first-hand. Actually, after doing more research on black hole lifetimes, I found out that the figure this page gives for black hole lifetimes (of 1.5×10⁶⁶ years for a 1 solar mass black hole) was reasonable, but I also realized that both this figure and the figure in Phys. Rev. D 13 198 were based on the assumption of massless neutrinos. Since neutrinos are no longer believed to be massless, the table will need further revision. See e.g. [4].
6. No, these sources are not okay as they are mirrors of Wikipedia.
7. When I visit this page it seems to be totally blank, but similar pages on the same site are also mirrors of Wikipedia, retitled and formatted in an odd way. So, this source also appears to be unusable.
8. No, don't start putting in names of large numbers again. The consensus is solidly against that.

Spacepotato (talk) 06:40, 8 July 2008 (UTC)

Re: Recent edits (3)

1. Since the start of the Stelliferous Era is given in years after the Big Bang, for consistency, all other times should also be given in years after the Big Bang.
2. As explained in [5], because the velocity of the Andromeda Galaxy transverse to the Milky Way is not precisely known, it is not certain that the galaxies will collide 3 billion years from now.
3. Again as explained in [6], the Andromeda Galaxy is approaching the Milky Way at approximately 120 km/s. The figure of 12.4 miles per second is not correct.
4. ApJ 531, 22 [7] gives a figure of 2 trillion years for the time at which galaxies outside the Local Group are no longer detectable.
5. As pointed out by User:Ashill, the term "star formation" is used much more frequently than "stellar formation".
6. As explained in ApJ 482, 420 [8], or Adams & Laughlin 1997 [9], §IIA, the lowest-mass red dwarfs are estimated to have a lifetime of between 10 and 20 trillion years. The figure of 100 trillion years is not correct.
7. Since the figure of 100 trillion years for red dwarf lifetimes is not correct, the figure of 200 trillion years for the time at which the last stars in the Universe cease to fuse is also not correct. Also, the paragraphs mentioning this figure which discuss the cessation of fusion at the start of the Degenerate Era and the creation of stars during the Degenerate Era are wholly redundant, as the article already discusses this more completely in the paragraphs immediately preceding and following.
8. In the paragraph on the destruction of planetary systems, it is clearer to explain the cause of the perturbations, which is an encounter with another stellar-mass object, rather than to just say "gravitational perturbations".
9. Likewise, the rewritten paragraph on the evaporation of galaxies is an improvement as it explains in more detail the physics of the encounters and what happens to the scattered bodies.

Spacepotato (talk) 19:01, 10 July 2008 (UTC)

Maldek New Edits

Here are my sources for my edits

These are my sources for the The Milky Way and the Andromeda Galxies Colliding in 3 billion years

Is there something wrong with all of them? If so what’s wrong with them?

http://www.galaxydynamics.org/tflops.html

http://csep10.phys.utk.edu/astr162/lect/galaxies/colliding.html

http://www.space.com/scienceastronomy/astronomy/galaxy_collides_020507-1.html

http://math.ucr.edu/home/baez/week252.html (Good Sun life)

These are my sources for our Galaxy being the only visible Galaxy from Earth in 3 Trillion Years.

Is there something wrong with all of them? If so what’s wrong with them?

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/

These are my sources that state that the smallest red dwarfs can live for over 100 Trillion Years.

Is there something wrong with all of them? If so what’s wrong with them?

Red Dwarfs can live for more than 100 trillion years. http://filer.case.edu/sjr16/stars_lifedeath.html http://filer.case.edu/~sjr16/advanced/stars_avgdeath.html

Thank You for your cooperation.Maldek (talk) 01:29, 11 July 2008 (UTC)

1. Re the possible collision of the Milky Way and the Andromeda galaxy, I would recommend that you read the Sky and Telescope article, [10]. As for your sources, the first, [11], implies that the collision is only possible and not certain ("one very plausible scenario puts them on a collision course in 3 billion years"). The second and fourth, [12] and [13], are only brief mentions and do not discuss the collision in detail. The third source, [14], also explains that the collision might not happen 3 billion years fron now ("If not on the first flyby, then within the second or third pass over the next 10 billion years...Even if there’s enough space between the Milky Way and Andromeda to simply brush past each other at spiral arm’s length, their mutual gravity will ultimately win out, drawing the two galaxies together on successive flybys.")
2. Re your sources on the disappearance of galaxies outside the Local Group, the second and third [15][16] are verbatim copies of a press release [17] from CWRU. The first [18] is a news story, apparently based on the press release. The fourth [19] is a verbatim copy of the first. The fifth and sixth [20][21] are mentions in passing. Rather than rely on the press release, which is a secondhand report on research done by Krauss and others, and the news stories, which are second- or third-hand, it's better to go to the original papers on which these sources are based. Also, the scientific papers explain the evidence and reasoning leading to the number, which the other sources do not.
3. Re your sources on red dwarf lifetimes, this is only one source as both pages are part of a set of web pages written by the same authors. These are brief mentions, and we don't know how the authors got these figures. They may be very rough estimates, or worse. The authors of [22] have modeled these low-mass stars in detail, as they explain in their paper. So, their number is more reliable. I have also discussed this in #My Sources for Heat death of the universe, above.
4. Re your recent edits:
   (a) 1.7×10¹⁰⁶+10⁴⁰ does not equal 1.7×10¹⁴⁶. Rather, it equals a number very slightly bigger than 1.7×10¹⁰⁶.
   (b) We should use the term star formation rather than stellar formation because, as I mentioned above, it's the term most other people use. There is no point in making up our own term.
   (c) There is no source for the Universe achieving a low-energy state after 10^1000 years.
   (d) There is likewise no source for the creation of 20 trillion solar mass black holes after 10^40 years.

Spacepotato (talk) 06:34, 11 July 2008 (UTC)

This edit summary claims that $1.7\times 10^{106}+10^{40}=2.077\times 10^{106}.$ In fact, to two significant figures, $1.7\times 10^{106}+10^{40}=1.7\times 10^{106}.$ Only if you go to 66 (!) significant figures is $1.7\times 10^{106}+10^{40}$ any different than $1.7\times 10^{106}.$ ASHill (talk | contribs) 20:26, 12 July 2008 (UTC)

Recent edits 4

1. Changing 10²⁶ into a 1 followed by 26 zeroes is a bad idea as it makes the number almost impossible to read: you can't tell whether it's 10²⁴ or 10²⁶ without counting the zeroes.
2. 1.7×10¹⁰⁶+10⁴⁰ does not equal 2.077×10¹⁰⁶. Rather, it equals 1.700000000000000000000000000000000000000000000000000000000000000001×10¹⁰⁶. It's reasonable to round this number to 1.7×10¹⁰⁶. Spacepotato (talk) 01:40, 13 July 2008 (UTC)

Edit war has to stop

This edit war is rather ridiculous and has been going on for nearly a month now (since June 24). Discussion on the article talk page is going nowhere, as different editors appear to be speaking different languages, particularly with regards to reliable sources. I think something needs to be done to make this stop, or at least make progress.

Would an outside opinion from WikiProject Astronomy or a formal request for comment help the editors resolve this? (A case could be perhaps be made against any of the involved parties, including me, for a temporary edit warring block. A request for page protection may be necessary to freeze the edit war somewhere.)

(I stumbled on this dispute recently, so I'm sort of but not really a third party.) ASHill (talk | contribs) 03:33, 13 July 2008 (UTC)

Justification for Exponents and 2.077x 10^106 years for beginning of Dark Era.

1. As you know 1.7x 10^106 plus 1.7x 10^106 equals 3.4x 10^106 so. Basically if you add a number to the same number it is twice that number. 10^6 plus 10^6 equals 2x 10^6. This means one million plus one million equals two million. So 2 times 1.7 equals 3.4. If you add 10^53 to 1.7x 10^106 it equals 2.55x 10^106 In the same way if you add 10^40 then you had .3773 to the number 1.7 to get 2.077x 10^106. Thank You.

— Maldek — continues after insertion below A more appropriate analogy is 1 million + 1 = $1\times 10^{6}+1\times 10^{0}$ = 1 million, to one significant figure. Similarly, $1.7\times 10^{106}+1.0\times 10^{53}=1.7\times 10^{106}.$ See Spacepotato's comment 2 above. ASHill (talk | contribs) 04:01, 13 July 2008 (UTC)

This arithmetic is based on the idea that 10⁴⁰/10¹⁰⁶ = 40/106 = 0.377. This is not so. By the law of exponents, 10^x/10^y = 10^x−y, so

10⁴⁰/10¹⁰⁶

= 10⁴⁰⁻¹⁰⁶

= 10⁻⁶⁶

= 0.000000000000000000000000000000000000000000000000000000000000000001,

which is much smaller than 0.377.

Spacepotato (talk) 04:43, 13 July 2008 (UTC)

2. I understand your rule that I cannot give names to numbers that are 10^15 or higher. I understand that, but now you have a new rule that I can’t write numbers using scientific notation. For example when I was writing 10^100 Septillion in scientific notation I wrote 10^1 followed by 26 zeros. This is scientific notation and you said that is what was supposed to be written. I understand that you are using tetration but people get confused by tetration and since all the other numbers before are expressed using normal scientific notation, it doesn’t maintain consistency throughout the article. For example before I started editing this article people would write 10^(10^26) as 10^10^26. This is obviously not the same thing. For example 3^3^3 equals 19,683 but 3^(3^3) equals 7.62 x 10^12. Big difference even in small numbers. People are often confused by tetration or exponential towers because they can’t see how much bigger a number actually is when it is condensed. This is why to avoid confusion and maintain consistency throughout the article I represent all numbers in scientific notation just like you said. And I removed all “large number” names of 10^15 and above. You said it was okay to list all numbers in scientific notation because it was easy to understand what the number represented. But now you say that I cannot represent the larger numbers with normal scientific notation which is more common and easier to understand among the average person. Why is this? When you use tetration (exponential towers) people are confused as to how big the number actually is because it looks smaller. They think 3^(3^3) is the same thing as 3^3^3 when there is a big difference. Because of this they will think that these numbers are much smaller than the other numbers given in the article , when in actuality there are enormously larger. If you don’t believe me look at the history of this article and especially article E19 s and more and you will see that for numbers such as 10^(10^26) I had added the parenthesis and whenever I did that somebody would edit it put 10^10^26 because they thought these numbers were the same thing even though 10^(10^26) is much much much much larger than 10^10^26. This is why to avoid confusion and to maintain consistency throughout the article I isted all the numnbers in normal scientific notation just like you told me to. If you use exponential towers on the large numbers than you will also have to use it on small numbers such as 10^11. All of the numbers would thus have to be represented in exponential notation because consistency is also one of your rules when reffering to time periods. So scientific notation is not okay to use? Should I convert all the numbers using exponential towers? How do you know when to write a number in scientific notation, and when to write a number using exponential towers? You just told me to write everything in scientific notation so I did and now you are changing your mind? Please respond to this message. Thank You for your cooperation.Maldek (talk) 03:48, 13 July 2008 (UTC)

1. If the exponent is sufficiently large, it's clearer to write it too in scientific notation, resulting in an exponential tower.
2. Exponentiation associates to the right: x^yz = x^(yz). So, 3^3^3 is the same as 3^(3^3), and is not the same as (3^3)^3 = 3^9. In any case, I put explicit parentheses into the exponential towers to avoid any possibility of misreading the towers.

Spacepotato (talk) 04:23, 13 July 2008 (UTC)

Black hole lifetime table—delete?

Is the black hole lifetime table (in the Heat death of the universe#The Black Hole Era, from 1040 years to 10100 years from now section) really necessary for this article? All that detail seems only tangentially related to the heat death. Moreover, the table borders on original research anyway because it's applying the cited equation (those numbers aren't in the cited source). ASHill (talk | contribs) 19:28, 14 July 2008 (UTC)

I deleted the table. I also deleted a few subsections on the future of the local group and local supercluster (diff) because these topics don't really seem relevant to the heat death; they aren't terribly related to the production of entropy. The material itself is certainly good, and might be more relevant in, say, timeline of the big bang or ultimate fate of the universe. If there is a good reason to keep the material here, it should be better explained. ASHill (talk | contribs) 14:38, 15 July 2008 (UTC)

Maldek's Comments for Ashills Edits

I am sorry I erased some important edits on the date of these theories but in order to undue many of the edits you made I had to undo all of them because if you have too many intermediate edits it won’t let you undo any of the earlier edits. The first thing I would like to bring up is that Spacepotatoe and I both agree on the Black Hole Chart. Actually it was Spacepotatoe’s idea in the first place to organize my data with into a chart. Spacepotatoe himself has found reliable research that is even more accurate than my data so he personally deserves credit for the exact dates of black hole disintegration. We all know all of Spacepotatoe’s sources are 100 percent scientifically accurate and reliable, so there is no arguing there. Spacepotatoe also deserves credit for adding the Coalescing of the Local Group which you erased. After Spacepotatoe added this new section on the Merging of the Local Group, I complemented the section with a new section that explained the process. This section was the Merging of the Milky Way and the Andromeda Galaxy, a sort of precursor to the Colascing of the Local Group. Then Spacepotatoe got 100 percent reliable sources and fixed my new section so that is 100 percent scientifically correct and appropriate for Wikipedia. So all 3 of the things you erased were approved by Spacepotatoe who used 100 percent scientifically accurate and reliable sources. Another thing is if you do not want the black hole chart, I can go back to the way I used the information before the Chart, which was creating a new section for each black hole mass. I could do that if you like, but I think you would like the chart displaying the black hole lifetimes more than my previous method, and I know for certain Spacepotatoe likes the Chart better since he created and pioneered it. Another thing is that Spacepotatoe has establisthed the correct lifetime for 20 trillion solar mass black holes at 1.7x 10^106 years. He has supplied 100 percent scientifically accurate and reliable sources for this figure. I know because originally I wrote 10^106 years for the lifetime of 20 trillion solar mass black holes and he told me about his perfect source that states 1.7x 10^106 years. So I would appreaciate it if you stopped changing the number to 10^100 years since it is not consistent with the article. Another thing is that you are erasing information about the Black Hole Era which both me and SpacePotatoe agree upon and, Spacepotatoe has once again supplied 100 percent scientifically accurate and reliable sources for it. So I would appreciate it if you stop erasing material from the article that has already been agreed upon by Spacepotaoe; Information which I support in firm belief of its 100 percent scientific accuracy and reliability. That is why I reverted the article back to the last edit by Spacepotatoe. Once again I am sorry I erased some important corrections that you made, but as I explained before in order to undo some of your earlier edits I had to undo your more recent edits because you cannot undo earlier edits if there are too many intermediate edits. Thank You for your cooperation. Thank You.Maldek (talk) 04:11, 16 July 2008 (UTC)

So, let's get this right! After waging a war with Spacepotato for the past few weeks, now you're his best buddy! This whole mess gets increasingly bizare!! CrackDragon (talk) 11:41, 16 July 2008 (UTC)

Where to begin?

1. It is entirely possible to revert only the edits you don't like; please do not revert all edits by a single editor simply because you don't like some of the editor's edits. If you need help, see WP:Reverting or ask me.
2. As I described above, I did not fully delete the material on the coalescing of the Local Group; I moved it to Timeline of the Big Bang. I agree that it was well written and reliably sourced; I just do not believe that the coalescing of the Local Group is related to the heat death, other than as an event that is occurring in the local universe at a time relevant to the discussion of the heat death. This is certainly a point on which reasonable people can disagree, but I do think that if the material is to be kept (or duplicated) here, its relevance to the heat death ought to be better explained.
3. The 10¹⁰⁰ yr lifetime of a galaxy-mass black hole is indeed consistent with the article and the Adams & Laughlin source; I see no source that states the 1.7 x 10¹⁰⁶ yr that you want to use. Applying that level of precision seems way over the top; we don't begin to understand black hole physics that well. My reading of Adams & Laughlin says that there's considerable uncertainty in the cosmological decade (the exponent: 100 or 106 are probably both within the range they argue for, although they don't explicitly state uncertainties); claiming that we know the value (1.7) to two significant figures is just absurd!
4. I repeat my concern about the original research nature of the black hole lifetimes, whether included in a table or a ridiculous large number of subsections.

1. What source lists the lifetimes of all of those black hole masses? (Yes, they can be calculated from the 1976 paper by Page.)
2. Why do we need to list all of those lifetimes anyway? Stating the lifetime of a solar mass black hole and a galaxy-mass (~10¹¹ solar masses) in the text seems plenty sufficient to give a reader a good idea of the appropriate timescales.

I'll also note that it's much easier to read your comments if you use concise paragraphs on single topics. ASHill (talk | contribs) 13:32, 16 July 2008 (UTC)

I have replaced my edits (diff) which I believe, based on the comments of Maldek above, were uncontroversial but that the editor reverted inadvertently in the process of reverting my controversial content edits. If I have done so in error, please let me know and I'll be happy to self-revert.

I'm leaving the subsections and table mentioned above in the article until we can come to a consensus. ASHill (talk | contribs) 13:51, 16 July 2008 (UTC)

1. Speaking from a bureaucratic point of view, I see no sourcing or original research issues with the table. The numbers come directly from (27) in Page. I agree though that the table is bulky and adds little to the article, so I have no objection if it is deleted.
2. We should use the 10¹⁰⁰ year figure as the boundary between the Black Hole and Dark eras, as this is the figure given in Adams & Laughlin.
3. Re the material about the isolation of the Local Supercluster, etc., I believe it is not appropriate to put it into Timeline of the Big Bang or Ultimate fate of the universe. The reason is that our material on the future of the universe is divided into a number of articles, depending on whether the universe expands infinitely in a finite time (Big Rip), recontracts (Big Crunch), and so on.
   We also have an article dealing with the case in which the universe continues to expand indefinitely. This is the article where these events belong. However, this article is currently the article we are discussing, Heat death of the universe. As User:Ashill points out, this is misleading, given the title. Until recently, we had another article, Big Freeze, on this subject, but it was redirected here. So, I suggest that the Big Freeze article be resurrected and the timeline be moved there, reserving this article for discussion of heat death per se.

Spacepotato (talk) 19:21, 16 July 2008 (UTC)

• Re 1: Perhaps the best place for the table is Hawking radiation#Black hole evaporation. (I agree that my original research concern is borderline, and I do think the table is useful, just not here.)
• Re 3: I thought Timeline of the Big Bang was the best place for the Andromeda/Milky Way collision, etc because Timeline of the Universe redirects there, and the Andromeda/Milky Way collision (or non-collision), at least, is soon enough that Big Rip/Big Crunch questions aren't relevant, but I'm not at all wedded to that opinion.
  Moving the timeline elsewhere and better focusing this article is a good idea, but I think Big Freeze is very similar to heat death and thus Big Freeze should redirect here; perhaps Timeline of an open Universe is more appropriate? Alternatively, a very slight modification to the opening of Timeline of the Big Bang could make it more appropriate to rename that article Timeline of the Universe. Certainly the preponderance of evidence these days suggests that the Universe will continue to expand indefinitely (although I wouldn't bet my retirement on that still being the view in 50 years). ASHill (talk | contribs) 20:09, 16 July 2008 (UTC)

Future of an expanding universe, or a similar title, would I suppose be the most accurate title for an article on the future in which the universe continues to expand indefinitely. Timeline of an open universe is problematic as a closed (positive spatial curvature) universe could also continue to expand indefinitely with a suitable value of the cosmological constant. Spacepotato (talk) 01:22, 17 July 2008 (UTC)

I agree that Future of an expanding universe is a good title, and I think splitting the detailed timeline off to that article makes the best organizational sense. I'd say let's do it. I've copied (most of) the relevant material to User:Ashill/Future of an expanding universe so it can be made into a standalone article before being moved to main space. Feel free to edit there. ASHill (talk | contribs) 16:34, 17 July 2008 (UTC)

I've moved the new timeline from user space to main space. At some point, I'll work on trimming the timeline on heat death to only include relevant material. -Alex (ASHill | talk | contribs) 14:56, 18 July 2008 (UTC)