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Space Science

Universe Has 100x More Entropy Than We Thought 304

Posted by kdawson
from the clean-up-your-room-that'll-help dept.
eldavojohn writes "Previous estimates are now thought to skimp on the entropy of the observable universe. The researchers contend that super-massive black holes are the largest contributor of entropy. Since they contribute two orders of magnitude more than previously thought, the total of all the observable universe is correspondingly higher. The paper highlights (in gruesome detail) new issues that arise with these new calculations — like estimating us a little bit closer to heat death (moving entropy totals from 10^102 to 10^104 out of a maximum of 10^122)."
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Universe Has 100x More Entropy Than We Thought

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  • Excellent! (Score:4, Funny)

    by Dyinobal (1427207) on Tuesday October 06, 2009 @12:29PM (#29659537)
    I can finally move forward with the plans for my Entropy Cannon.
  • Heat Death (Score:5, Informative)

    by Anonymous Coward on Tuesday October 06, 2009 @12:30PM (#29659565)

    Here's a link [wikipedia.org] for anyone curious about the Heat Death of the Universe concept

    • Re:Heat Death (Score:5, Interesting)

      by MozeeToby (1163751) on Tuesday October 06, 2009 @12:55PM (#29660023)

      It's interesting to note that even with the new estimate being 100X greater than the old, the new data is still only a billionth of a billionth of the maximum value. What, if anything, does that mean for the past and future of the universe? Reminds me of the Stephen Baxter book Manifold: Time, where the age of stars and galaxies is thought of in the same way we think of the instant right after the big bang.

  • Fourth Law (Score:5, Funny)

    by T.E.D. (34228) on Tuesday October 06, 2009 @12:37PM (#29659675)
    I propose a Fourth Law of Thermodynamics [wikipedia.org]: There's more entropy than you think there is.
    • Re: (Score:2, Informative)

      by salahx (100975)

      Fourth Law of Thermdynamics [wikipedia.org]: There's always more entropy then you think there is, even when you take into account the Fourth Law of Thermodynamics.

      I still wouldn't worry about the heat death of the universe [wikia.com], though, unlike those in the aforementioned link.

      • by Aphoxema (1088507) * on Tuesday October 06, 2009 @01:06PM (#29660185) Homepage Journal

        Fourth Law of Thermdynamics [wikipedia.org]: There's always more entropy then you think there is, even when you take into account the Fourth Law of Thermodynamics.

        I still wouldn't worry about the heat death of the universe [wikia.com], though, unlike those in the aforementioned link.

        You forgot to recursively account for the fourth law, you fool! The death of the universe will now be exponentially sooner every moment that passes!

      • by T.E.D. (34228)

        I always found the last phrase of Hofstadter's law to be an unnesecary crutch for the logically impaired. Plus it removes most of its punch. I didn't feel like making the same mistake myself.

        Having spent better part of the last decade engaged in a sysephian struggle to clean a house inhabited by three children and two working adults, you might notice that I've given this issue a lot of thought already.

    • There already are four laws of thermodynamics.
      • There already are four laws of thermodynamics.

        Just because there are four of something does not necessitate that one of them is the fourth.

        There are four laws of Thermodynamics. One of them is the 0th.

    • by anorlunda (311253)

      Good one T.E.D. I'll remember that one and use it some day.

  • gosh (Score:3, Funny)

    by phantomfive (622387) on Tuesday October 06, 2009 @12:37PM (#29659687) Journal
    Things are just falling apart all over!
  • discovery (Score:5, Funny)

    by unjedai (966274) on Tuesday October 06, 2009 @12:42PM (#29659769)

    Universe Has 100x More Entropy Than We Thought

    Scientists must have discovered my daughters room.

    • by royallthefourth (1564389) <royallthefourth@gmail.com> on Tuesday October 06, 2009 @12:46PM (#29659859)

      Universe Has 100x More Entropy Than We Thought

      Scientists must have discovered my daughters room.

      No, but the football team sure has!

      • She's eight, you insensitive clod!

      • Re:discovery (Score:4, Insightful)

        by ObsessiveMathsFreak (773371) <obsessivemathsfreak@nosPAm.eircom.net> on Tuesday October 06, 2009 @01:58PM (#29661073) Homepage Journal

        Football plays and players clearly show that simple bodies can form spontaneous order. This result was found to be in direct opposition to the prevailing dogma of the second law of teenodynamics; That the disorder of a teenagers life, property, and living space will always increase over time. This breakthrough is thought to have bearing on the great problem of "Teenage dysfunction death" which asks why when teenagers continuously degenerate over the course of their teen years, so they eventually mature into productive and stable adults.

        Scientists urge caution in relation to these findings. "Current teenage theory leaves many questions unanswered", said Professor Alex Tweed of the national institute for Juvenile Entropy studies, "However, one result does not explain all the data on its own. For example, we know that there are quite a few adults who never become stable or mature. For example, many can be found making tasteless jokes about peoples' daughters on web forums, and other can be found modding up those same comments. This field will require more research before a definitive understanding of human maturity is achieved."

    • by macraig (621737)

      Was it attacked by a blender?

  • So, it looks like we are closer to the novel than previously thought? And rather than witnessing the "end of the univers" (with dinner and wine) we are observing the cleaning crew (black holes) picking up the ... er ... mess?

  • we're doomed anyway (Score:5, Interesting)

    by prgrmr (568806) on Tuesday October 06, 2009 @12:51PM (#29659933) Journal
    Because of Neutron decay [wikipedia.org] we've only 10^49 years anyway.
    • Free neutrons decay. Helium (and many other) nuclei are forever stable, because the energy gain in neutron decay is less than the nuclear binding energy. Lower energy states are only available through fusion, with an optimum at Iron (where they'll be met by nuclear fission from the other side).
  • by the_rajah (749499) * on Tuesday October 06, 2009 @12:52PM (#29659957) Homepage
    Oh, wait... that's going to happen anyway.
  • FTA: A black hole is the entropy champ because there are myriad ways for all the material that has fallen into it to be arranged microscopically while the black hole retains the same numerical values for its observable properties -- charge, mass and spin.

    So a black hole's entropy = "we don't know by looking what's inside"? How exactly does that contribute to the heat death of the universe? If there was a million times more entropy in black holes, how would it effect existance outside of black holes? Is t

    • by kalirion (728907)

      Yeah, should've used "affect" instead of "effect" (preempting grammar nazis).

      Sure there are other grammar errors tho.

    • by Aladrin (926209)

      Should have used a car analogy.

      It doesn't matter how much dirt is in the gas in the can in the back of the car if the gas in the car's tank is pure. Siphoning the car's gas into the gas can isn't going to make the car die, either.

    • by mea37 (1201159) on Tuesday October 06, 2009 @02:01PM (#29661105)

      I'm afraid the BAC analogy really isn't appilcable. You're describing an impurity which builds up to a critical level to "kill" the host, and pointing out that if you could sequester the impurity the sequestered quantity wouldn't matter. Entropy is not an impurity that is slowly building up to eventually cause the universe to break; it's nothing like that at all.

      I find it conceptually confusing to think about entropy as a finite/positive quantity. The way it's defined mathematically, of course, it is ... but at a physical level there's just something backwards about it.

      Entropy describes the degree to which energy in a system isn't usable. If you consider as a closed system a bit of ice in a glass of hot water: the heat in the water is "useful" in this system. It will melt the ice, and then equalize the temperature of the water from the melted ice to that of the rest of the water. (That may not seem "useful"; I suppose the point is other processes could capture and use the energy for other ends.)

      But, as the ice melts and the water temperature equalizes (or as any other process fuels itself by accelerating this process), you don't run out of energy (which is constant) - but you do run out of "usability" of energy. When your system contains only water at a fixed temperature, there is no way to make heat flow, and all of teh energy in the system is useless. (Again, this assumesa closed system.)

      So the point with black holes is, they aren't sequestering entropy to keep it from harming the universe in some way (like your BAC example); if anything they sequester energy and keep it from interacting with the rest of the universe, rendering it useless. (Not sure how Hawking radiation fits in that analysis, though.)

      • by kalirion (728907)

        So the point with black holes is, they aren't sequestering entropy to keep it from harming the universe in some way (like your BAC example); if anything they sequester energy and keep it from interacting with the rest of the universe, rendering it useless.

        If that's all it is, than basically what this article is saying is that "black holes account for 100 times more of the total mass of our universe than we thought", instead of "a black hole of a given mass has 100 times more entropy than we thought"? I can

  • Dark Energy (Score:4, Insightful)

    by russotto (537200) on Tuesday October 06, 2009 @01:01PM (#29660105) Journal

    With the "news" (circa 1998) that the rate of expansion of the universe is increasing, it seems to me that worries about the heat death of the universe should be put on hold. There's something (currently labeled "dark energy") about cosmology that we simply lack sufficient understanding of.

    • With the "news" (circa 1998) that the rate of expansion of the universe is increasing, it seems to me that worries about the heat death of the universe should be put on hold. There's something (currently labeled "dark energy") about cosmology that we simply lack sufficient understanding of.

      Yes, the president should select the "Astrophysics Center" and move the "heat death" slider to 0 and the "dark energy" slider to 100. We must find the chosen one to combat this "dark energy" threat!

      • the president should select the "Astrophysics Center" and move the "heat death" slider to 0 and the "dark energy" slider to 100.

        I've seen this in the Oval office, it's actually just an Etch-a-Sketch.

  • by rwa2 (4391) * on Tuesday October 06, 2009 @01:06PM (#29660177) Homepage Journal
    The universe is still expanding in all directions at the speed of light, then the entropy per unit volume will still stay low enough to be habitable, right? Or is the problem that the rate of increase in volume will not keep pace, since it takes longer and longer for the universe to double in volume at a constant rate of expansion?
    • Not RTFA.
      TFS fails to use them, so I must ask,
      What are the units of entropy? Can they be useful at a macroscopic level... like in describing how much entropy your bedroom contains (before it simply must be cleaned)?
    • Re: (Score:3, Interesting)

      by Max_W (812974)

      Where the universe is expanding? Into another universe? Into emptiness? Into nothing? Is there any rational explanation? Or is it unknown yet?

  • by argent (18001) <peterNO@SPAMslashdot.2006.taronga.com> on Tuesday October 06, 2009 @01:12PM (#29660299) Homepage Journal

    So if I connected my server's entropy generator to a black hole I'd never have to type a page full of gibberish to generate my SSH key pair again!

  • So does this mean that the time it takes to evenly spread the matter / light which is not swallowed by the black holes is shorter than we thought previously?

    I read through all the articles now, and I still don't have a clue.

    What than, will the big black holes (without mass surrounding them) merge to a new gigantic super massive singularity effectively reseting the universe and causing the next big bang, and the next round?

    I'm so confused..

  • by loafula (1080631)
    that's all i can say
  • I did not know that 9 chevrons dialing need that much power.

  • Messier (Score:3, Funny)

    by ozbird (127571) on Tuesday October 06, 2009 @04:14PM (#29663043)

    A new calculation of entropy upholds that general result but suggests that the universe is messier than scientists had thought

    I propose a three level scale: Messy, Messier [wikipedia.org], and Messiest objects.

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