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Science

Stars Could Shine In Many Universes 309

A commonplace of cosmologists who argue the anthropic principle is the assumption that if any or a few of the constants of nature took on an even slightly different value, life could not have evolved — perhaps even stars and galaxies would not form. Science News reports on a new calculation showing that, to the contrary, star formation could happen in up to one-quarter of universes with different values of three important constants. "In fact, all universes can support the existence of stars, provided that the definition of star is interpreted broadly," said the researcher, Fred Adams. "...calculations suggest that, contrary to some previous claims, stars are not only common in our cosmos but are also ablaze in myriad other universes, where the laws of physics may be drastically different... Had Adams found that the range of parameters that allowed for stars was very small, that would have suggested that the laws of physics in our universe have been 'fine-tuned' to allow for star formation... Instead, Adams' study shows that our universe doesn't seem particularly special in that regard."
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Stars Could Shine In Many Universes

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  • Zug zug (Score:5, Funny)

    by Anonymous Coward on Sunday August 17, 2008 @03:50PM (#24637269)

    I dont read slashdot for 2 days and I missed the fact that there are more than 1 universes... shit!

    • Re: (Score:3, Insightful)

      by Swizec ( 978239 )
      Err ... isn't the base principle of string theory that there is an infinite number of spacetimes ie. universes out there?
    • by Anonymous Coward

      I dont read slashdot for 2 days and I missed the fact that there are more than 1 universes... shit!

      Only physicists can get away with this sort of crap. Any other field of science would be up in arms. Where is the falsifiability, asks Sir Karl Popper in his grave?

      Louis Savain

      Rebel Science News [blogspot.com]

      • Re: (Score:3, Funny)

        Pretty much. In fact, all universes could have stars given that your parameters for what constitutes star is broad enough. In our universe, it's a ball of incandescant gas, in another universe it's a radioactive rock, in another universe it's a feces throwing monkey. Not much to see here. How clever.

        This isn't science, it's philosophy.

      • Re: (Score:2, Informative)

        by orkysoft ( 93727 )

        This isn't positing the existence of multiple universes at all. This is about the question why the universal constants are what they are, and what would have happened if they were different.

        Something completely different from M-theory.

      • by MightyMartian ( 840721 ) on Sunday August 17, 2008 @06:27PM (#24638795) Journal

        Would you all screw off about Popper. No one has ever done science the way Popper said they do, and even he backed off on is ridiculous claims in later years.

    • Re: (Score:2, Informative)

      by Blazeheart ( 1330013 )
      Universe, uni- means 'one' (duh). So you think if there is one '-verse' then there is probably more. All of the universes together is called the multiverse or meta-universe.
  • so (Score:5, Interesting)

    by thermian ( 1267986 ) on Sunday August 17, 2008 @03:51PM (#24637277)

    This hypothesis, if true, shows that the universe is actually a rather robust structure.

    I like that a lot more then the 'one tiny bit off and you get nothing' thing. It sounds more plausible to me.

    • Re: (Score:3, Funny)

      by niceone ( 992278 ) *
      Yes, the design is so good it works even if the 'constants' are way off. Convinces me, now I just need to work out which religion to sign up for!
      • Re: (Score:3, Insightful)

        by arminw ( 717974 )

        ....now I just need to work out which religion to sign up for!....

        A god worth worshiping would have to be transcendent, outside and beyond our universe, not Limited to the dimensions of time or space. Such a God would also be capable of accurately predicting the future, never missing even once. He should also be capable of entering time and space and showing that he had power over nature and even death itself.

        There is a collection of books claimed to be the Word of God which we call the Bible. The word "un

    • Re:so (Score:5, Insightful)

      by cathector ( 972646 ) on Sunday August 17, 2008 @04:07PM (#24637437)
      > the universe is actually a rather robust structure.

      .. at least w/r/t star formation.

      slightly OT, the thing i really dislike about Intelligent Design arguments is that they're essentially a way of just giving up trying to explain things. they equate to "it's irreducibly complex, therefore we can learn no more", or "the chances approach zero, therefore we can learn no more". but science constantly discovers new things, throws old things out, etc. an essence of science is *not* deciding you've learned as much as you can or that you've arrived at the ultimate explanation.
      • Re:so (Score:5, Insightful)

        by wrf3 ( 314267 ) on Sunday August 17, 2008 @04:26PM (#24637639) Homepage

        How did this tired chestnut become a meme among supposedly smart people? "God did it" refers to agency, just like "time and chance" refers to agency. The "how" is a completely different matter. As a child, I remember asking my father, "How did you do that, Dad"? If anything, it whetted my curiosity to know more.

        Whatever position one holds on the "irreducible complexity" argument, the argument is not "therefore we can learn no more." Rather, the argument is "the agency of time, chance, and unguided selection couldn't be the cause of such-and-such an object."

        • Re:so (Score:5, Interesting)

          by cathector ( 972646 ) on Sunday August 17, 2008 @04:48PM (#24637861)

          good clarification.

          yes, i was limiting the scope of agents to those admitted by "accepted science".

          so with scoping in mind, my complaint is that irreducible complexity arguments tend to translate into "accepted scientific agents do not currently explain such-and-such, therefore we must look outside accepted scientific agents".

          .. which strictly speaking, yes, proper scientific method can't shut the door out-of-hand on agents such as gods. for example, consider a world in which gods actually did create such-and-such. if the scientists of that world always reject gods as possible agents, then they will clearly never arrive at the correct explanation of such-and-such.

          however, appeals to agents outside the scope of accepted science have historically always fallen, so it seems prudent not to resort to them now, and instead to keep hammering on the stuff within accepted science. qv the god of the gaps, etc.

        • Re: (Score:2, Flamebait)

          by thermian ( 1267986 )

          Whatever position one holds on the "irreducible complexity" argument, the argument is not "therefore we can learn no more."

          Its my understanding that "irreducible complexity" means "we can make millions selling this idea to brainless idiots".

    • Re:so (Score:5, Insightful)

      by hardburn ( 141468 ) <hardburn.wumpus-cave@net> on Sunday August 17, 2008 @04:25PM (#24637613)

      As already pointed out by another reply, this only applies specifically to star formation, which was just one piece that has to be in place for life to work out. Even if this particular one has a 25% chance of happening, there are still a lot of others. Like existing long enough to make heavy elements, or having the right ratio between gravity and electromagnetic forces.

    • I understand that this may or may not be true, but scientists still don't really understand what the gravitational force is, nor do they understand the role of dark matter or dark energy. I think we have a long ways to go before we can make any realistic conjecture on any of this.
    • by beh ( 4759 ) *

      I am a bit weary of scientists telling us that 'life' wouldn't be able to form if certain things were slightly different...

      I think life could potentially evolve in a lot of completely different universes with completely different values for the 'constants of nature'. Maybe stars wouldn't form - but if there is matter, maybe something else might form out of it.

      It just wouldn't look like anything you might have seen in Star Trek, Star Wars, or any other SciFi movie, series, or story...

      Similarly to a creature

      • Re: (Score:3, Interesting)

        by fm6 ( 162816 )

        Scientists are saying no such thing. The argument is not that a universe that is slightly different could not support any life. The argument is that is could not support human life. For example, Fred Hoyle argued that if certain physical constants were just a little different, carbon atoms could not form ring-shaped molecules. All life as we know it is based on those carbon rings, so those changes would preclude our existence.

        And before you start picking at flaws in that argument, let me point out something

    • by Roger W Moore ( 538166 ) on Sunday August 17, 2008 @05:05PM (#24637995) Journal

      This hypothesis, if true...

      The Standard Model has 19 free parameters [wikipedia.org] (not including G) and even more if you include the new neutrino mixing results. This guy varies TWO of them plus G and then claims that 25% of possible universes would form stars? I remain completely unconvinced. While the strength of gravity, EM and the strong interactions may be important for stars the other parameters control some other vaguely important things like whether there is any matter in the universe.

      In addition these parameters also have major effects directly on the functioning of stars. For example if the electron mass were larger the orbit of the electron in the atom shrinks and fusion becomes a lot easier [wikipedia.org]. One would presume that this would greatly affect star formation. In addition there are other effects caused by varying the parameters: tweaking with these may well change the type of matter in the universe such as less hydrogen and more helium etc. He does at one point mention this and then states that he would not expect it to vary much from our universe without giving a reference. To me this seems completely non-obvious but I'm not a cosmologist so perhaps it is obvious to them?

      So as I said I remain totally unconvinced that this paper really shows anything meaningful at all.

      • I also qualified my reply with 'if true'.

        All parameters are not created equal, he may have picked up on something rather interesting.

        Or not, it requires more investigation.

        • Re: (Score:3, Interesting)

          I also qualified my reply with 'if true'.

          I understood that. I was commenting that I thought it very unlikely to be true based on the evidence presented.

          All parameters are not created equal, he may have picked up on something rather interesting.

          I doubt it. There are very clear reasons to expect other parameters to greatly affect the formation of stars. As far as I can see he has not commented on this at all. This means that either:

          • There is some good reason, so obvious to other cosmologists that he need not explain it, which precludes these other parameters from affecting his conclusions
          • He is deliberately ignoring the effects of other
      • The Standard Model has 19 free parameters ... This guy varies [just] TWO of them plus G

        But varying the other 16 produced hairy women, so he skipped them.
             

    • I like that a lot more then the 'one tiny bit off and you get nothing' thing. It sounds more plausible to me.

      I'm not convinced in the slightest that a multiverse exists (in any sense of the word), but I agree that assuming things like Brane cosmology are true, the logical conclusion is that these other universes would, based on probability, have something recognizable to us as 'stars' and even 'life'

      Possibility always wins when we play the probability game.

      As I said above, I think the multiverse theories ar

      • by thermian ( 1267986 ) on Sunday August 17, 2008 @05:49PM (#24638441)

        As I said above, I think the multiverse theories are a pantload of stink.

        The interesting thing about a way of describing the universe is that it doesn't have to be true to be userful, provided it produces useful results.
        Think for a moment of Copernicus.

        His model wasn't accurate at all, not even slightly, it was nowhere near as useful in real terms then the Ptolemaic model, but it allowed the universe to be viewed in a different way, eventually leading to our current, vastly more accurate description.

        Ours too may be wrong, but you need ways of describing reality which produce useful results. They don't have to be 'real' to be useful.

        • you speak wisdom, and I am always in favor of thought experiments and 'what if...' especially in cosmology

          it allowed the universe to be viewed in a different way

          Yes. here is my point, I do not think the way we are currently viewing the universe (as a part of a multiverse) is useful. I think we can do better.

          ex: we could view the universe as a massive confluence of zip drive dandylions that nunchuck the higgs anti-bosons into oblivion then refresh them via the Kobe/Shaq bridge at a rate of 5!/cat in Krull-sp

          • I find it somewhat implausible myself, but I wouldn't know how to go about revising it.

            I dabble in physics, but I don't stray beyond the Newtonian model because my research is purely concerned with the practical realities of route finding in space.

  • by Nom du Keyboard ( 633989 ) on Sunday August 17, 2008 @03:56PM (#24637345)

    A commonplace of cosmologists

    That's funny, I always thought they came in herds.

    Or maybe in packages - contents may have expanded during shipping.

    • Re: (Score:2, Funny)

      by Anonymous Coward
      It's a cluster of cosmologists, a phalanx of physicists, an aggregation of astronomers...
  • Still dumb (Score:5, Interesting)

    by Bombula ( 670389 ) on Sunday August 17, 2008 @04:02PM (#24637389)
    So science uncovers yet another way in which our world and universe are mediocre instead of special. Is this surprising? Even if the universe were fine tuned so that the characteristics we see are a unique product of its basic configuration, what's to say there aren't an infinite number of other universes which also harbor unique characteristics as a result of their own basic configurations - features that may make them more conducive to what we would call life? Perhaps there are universes in which life is fantastically abundant and our universe is, by comparison, a bland underperformer? Or perhaps life is itself a silly concept? Maybe whole universes are organized such that they are sentient. Perhaps even in our own universe there is complexity in dark matter and dark energy that might be called life, perhaps in great abundance (there is, after all, much more dark matter and energy). Or perhaps rules of logic and consistency - the basis of mathematics, upon which we interpret our universe's configuration - is itself specific to our universe, and in other universes logic and consistency look different or aren't even meaningful.

    Even if we are rare, why does that make is so special? It's rare to win the lottery, but it's got to happen to someone doesn't it? If we hadn't won the lottery, we wouldn't be here to talk about it, would we?

    • So science uncovers yet another way in which our world and universe are mediocre instead of special. Is this surprising?

      No, it isn't. I think we need a better definition of the anthropic principle. My proposal is: "There is at least one universe which contains at least one species thinking it's the center of said universe."

    • Re: (Score:3, Interesting)

      by Chappster ( 1169005 )
      The anthropic principle is one of Creationists' favorite argument for the 'proof' of the existence of god. It is one of the most annoying, under-the-belt argument that has absolutely no actual bearing on anything whatsoever, but philosophers like Dinesh D'Souza play with it like a flute.

      With studies like this, that argument is useless. It shows that the philosophers who use this argument are just blowing steam out of their pompous asses without any actual research. I really wish that I could see the faces

      • Re: (Score:3, Insightful)

        by Anonymous Coward

        The anthropic principle is one of Creationists' favorite argument for the 'proof' of the existence of god.

        The anthropic principle is only "'proof' of the existence of god" if it is misinterpreted. Simply stated, it describes the selection bias at play in humanity's observations of the universe. Increasing the number of universes that can support stars (much less life) has no bearing on the anthropic principle, as either way we're 100% sure we live in a universe which does support both.

      • So you're resorting to this multiverse crap to disprove someone? I'm sure Mr. D'Souza will thank you.
        • Re: (Score:3, Informative)

          by Chappster ( 1169005 )
          As if there's something wrong with the multiverse theory? The theory itself isn't hard at all to understand, and it doesn't even need string theory as a backbone of proof. The theory is relatively simple. There's three theories that I can think of that back up the multiverse theory, two of them which I completely disagree with. One is the brane theory, another being the idea that every quantum reaction creates its own universe. But there's another one that sounds the most plausible of the three. Back whe
          • Re: (Score:3, Insightful)

            There is something wrong with it: lack of hard evidence. Sure, it is easy to understand how it could be true, but we simply don't know if it is. By the same accord, it easy to understand how an all powerful being, possibly from a higher dimension (aka God), could have created the universe, but you run into the same problem, a lack of solid scientific evidence. IMHO, you are viewing the multiverse concept through rose colored glasses simply because it sounds more scientific.
        • You don't need multiverses, just a cyclical universe with infinite Big Bangs/Big Crunches. Each Big Bang throws the dice and resets the constants. Since there's an infinite number of universes in the past and the future, our universe has to show up eventually.
          • Re:Still dumb (Score:4, Informative)

            by jamesh ( 87723 ) on Sunday August 17, 2008 @08:23PM (#24639665)

            Each Big Bang throws the dice and resets the constants

            Until it sets g too low and the universe expands forever instead of collapsing, or time doesn't increment. Or maybe our glorious intelligent designer has put a constraint in to make sure this can't happen :)

    • by xPsi ( 851544 ) *

      So science uncovers yet another way in which our world and universe are mediocre instead of special. Is this surprising?

      I agree this isn't surprising. However, the reason this isn't "dumb" has to do with difference is between just letting your imagination run wild and actually doing a physics calculation to find specific alternative stable configurations of physical law.

    • Re:Still dumb (Score:5, Insightful)

      by Artifakt ( 700173 ) on Sunday August 17, 2008 @04:59PM (#24637945)

      There are several kinds of low probability events. A lottery has a low probability of any one ticket winning, but a very high probability that somebody will win because there are so many tickets. For universes to work like that, there have to be enough universes that as you put it, "it's got to happen to someone". Science hasn't "uncovered" (again, your word) this situation, unless they have proved that parallel universes definitely exist, there are definitely enough of them for the low probabilities to sum, and the meta-laws of these universes allow summing the low probabilities.

      Uncovered would mean:
      1. Scientist observes parallel universes.
      2. Scientist counts enough of them to prove the low odds can sum to likely odds, or finds a good proof there are enough. A good proof has to be more rigorous than is usual in physics, because our universe's physics may not be the ruleset in any of these others. Probably this means the proof has to meet formal mathematical standards.
      3. Scientist has to have a Theory of Everything for our universe.
      4. Scientist has to derive similar theories for the other universes and a meta-theory that combines them.
      5. Scientist then has to show that the meta-ToE allows low probability events to sum.

      I'm pretty sure none of those steps have happened. If I'm wrong, I'd like to predict what discoveries get awarded the next ten Nobel prizes in physics, and probably a Fields medal or two.

    • Perhaps there are universes in which life is fantastically abundant and our universe is, by comparison, a bland underperformer?

      What the anthropic people are talking about is "life just like me." They're not talking about what's flourishing near our undersea thermal vents, by and large, what grows under the Antarctic ice, or if we find any, what grows on Mars.

      AFAICT, life adapts to its environment. One would expect different forms of life under different conditions.

      Or perhaps life is itself a silly concept

    • Re: (Score:3, Insightful)

      by dmartin ( 235398 )

      The important part about this idea is that the universe is more mediocre than we expected. Specifically cosmologists are interested in asking the question

      Pretend that the laws of physics are given and don't change. But we will allow the parameters (e.g. the amount of matter, or the value of the cosmological constant) to change. How much can the parameters change before the universe looks significantly different?

      What does "significantly different" mean? Originally our ego-centric view promoted the idea of "c

    • So just how is "they exist but it is mathematically impossible for them to affect our universe in any way or for us to measure them or conduct any empirical experiment upon them" any different from "they don't exist"? Are they, perchance, Invisible Pink Universes?

      As for "winning the lottey", the question "why is the universe like it is" has only ever been a side-issue to the bigger question "why should any universe whatsoever exist at all -- the empty set is perfectly mathematically self-consistent; why sh

  • Finally! (Score:5, Funny)

    by seanonymous ( 964897 ) on Sunday August 17, 2008 @04:02PM (#24637393)
    I can't wait to meet the evil me and see how I look with a pointy beard.
  • So now we've got to be worried about aliens from different UNIVERSES as well?

  • weakless universe (Score:4, Interesting)

    by xPsi ( 851544 ) * on Sunday August 17, 2008 @04:28PM (#24637661)
    Here's another similar idea trying to construct a so-called "weakless" universe [arxiv.org], where no weak nuclear interactions exist (see abstract below). A bit technical, but good stuff.

    "A universe without weak interactions is constructed that undergoes big-bang nucleosynthesis, matter domination, structure formation, and star formation. The stars in this universe are able to burn for billions of years, synthesize elements up to iron, and undergo supernova explosions, dispersing heavy elements into the interstellar medium.

    There's no evidence such universes exist. But it is still a good exercise to help keep some perspective on what is possible, even in principle, given what we know about physical law. It also highlights that people who make "anthropic principle-like" claims based on fine-tuning haven't bothered to go back to the underlying laws of physics and actually look for other stable configurations, even in theory.

  • by cmacb ( 547347 ) on Sunday August 17, 2008 @04:29PM (#24637671) Homepage Journal

    I continue to be bothered by the use of the word "universe" to mean something other than "everything". Having to substitute "multiverse" to replace the word that didn't need to be replaced (rather a new word should have been invented for the new concept) bugs the crap out of me so much so that I hope all these new theories are proved wrong so we can maintain continuity of the language.

  • No one has brought up the obvious point that this indicates what we call "constants" don't need to be constant to fit with the stars we see?

    Or at least they need to be less constant than originally believed?

  • The usual anthropic principle argument about formation of stars relates to the cosmological constant (yes we have one of those again, at least if there's anything to dark matter and dark energy). That constant is very, very poorly predicted by some particle physics models such as the ones that predict a Higgs boson. The observations suggest a value that is a full 120 orders of magnitude less than the prediction. If that value were as little as 119 orders below the prediction, cosmic expansion would prevent

  • by Pfhorrest ( 545131 ) on Sunday August 17, 2008 @04:47PM (#24637859) Homepage Journal

    Proponents of the Anthropic Principle do not claim that universes which cannot support life are rare, or commonplace, or anything of the sort.

    The Anthropic Principle merely says that we should not be surprised to find the universe conductive to our existence, even if such conditions are highly improbable, because the fact of our existence logically necessitates that we exist in a universe conductive to it.

  • by 4D6963 ( 933028 ) on Sunday August 17, 2008 @04:49PM (#24637863)

    This research is great because it points out that the constants and such that the universe exhibits aren't so special, however the way it's presented is quite ridiculous.

    Firstly, these "universes" are purely theoretical, and they're function of the modification of a few constants, that doesn't mean they're actually out there.

    Secondly, I just hate it when people say "myriads/an infinity of other universes". What you really mean by "infinity" in that case is not a large number of discrete universes, but continuous variations of a universe. Presenting something continuous as an infinite amount of discrete things is stupid and misleading, although somehow correct. Sure you can iterate some constant by the smallest increments you want, so you can cut the whole thing into an infinity of possibilities, but just because you're sampling something continuous discretely doesn't make it cease from being continuous and not discrete. That's exactly like saying the 3D space universe is actually made of an infinity of stacked up 2D universes that communicate between each other. A completely arbitrary way to look at things that misleads you on the real nature of things.

  • that the universe is truly just a 4 quadrant cube with 4- 24 hour days rotating simultaneously within 1- 24 hour rotation of a 4 quadrant created earth?
  • So is it just me, or is this just crazy theoretical stuff made up by mathematicians, with absolutely zero empirical evidence to support any of it?

    He finds that stars are stable entities in roughly one-fourth of the universes he considered.

    Come on. Now I know he's just making stuff up. He thought up some imaginary universes, and discovered that a quarter of them can have stars. Despite being printed in Science News, this isn't science. Maybe it's interesting math, but that's all.

    And you people think Creationists are nuts...

    • by gmuslera ( 3436 )
      You can write a number that is bigger than the amount of elemental particles in the universe. That number is "theoretical" too, as cant be the count of anything physical. Still, is common place in a lot of areas to use infinite (probably bigger than that number) for practical things.

      This whole thing remembers me Q proposing to redefine some universal constants to solve a problem in ST:TNG, and that idea was actually used in a particular way to solve it, go in that direction if you want to find something rea

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