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Science

Cyclic Universe a Possibility 403

Posted by michael from the come-on-let's-make-another-revolution dept.
An Anonymous Coward writes "Spacedaily has a post(from Science) about a new theory at odds with the big bang theory. The researchers claim that this theory of an oscillating energy field could be experimentally tested in the coming years."
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Cyclic Universe a Possibility More

Cyclic Universe a Possibility

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  • A collapsing universe has long been a hypothesized. It would be interesting if this were true, because it implies that each universal state is discrete and has a finite lifetime. I wonder how much time our universe has left?

    -Sean

  • All Things Considered (Score:5, Informative)

    by EReidJ ( 551124 ) on Sunday May 05, 2002 @01:03PM (#3465956) Homepage
    On April 25, All Things Considered [npr.org] on NPR [npr.org] did a five-minute story [npr.org] on this new Science article. Highly recommended, gives some good background not only on how this theory fits better with some of the current data that we are collecting, but also talks about how difficult it is for a new theory to gain acceptance in the scientific community when it flies in the face of a long-established theory.
    • how difficult it is for a new theory to gain acceptance in the scientific community when it flies in the face of a long-established theory
      Hmmmm, like homeopathic medicine. Take a sugar pill no matter what ailment you have. The very thought can cure anyone. What was that new research that the scientific community tried to killed about H2O having the ability to form lattices of introduced molecules or something?

  • Uh oh... (Score:3, Interesting)

    by adam613 ( 449819 ) on Sunday May 05, 2002 @01:04PM (#3465958)
    This one might piss off the religious right. The Big Bang could sort of be reconciled with the idea that God created the world in 7 days, since maybe the Big Bang happened on the first day. But the idea that the universe has always existed (and therefore predates creation) is a big problem, since it excludes God from the picture.

    I'll be interested to hear the religious responses to this theory.

    • Re:Uh oh... (Score:3, Insightful)

      by wadetemp ( 217315 )
      The problem with reconciling the Big Bang theory to a religious belief (which is something I actually do) is that it is farily obvious that God existed *before* He "let there be light." God was not created by the bang; He was already there before the first day. There's nothing (in the Bible anyway) that says there was not a prexisting work before He decided to chuck it and make a new one... and if there was, why bother telling us? Maybe the point is that we figure that out ourselves? :)

      • Re:Uh oh... (Score:3, Interesting)

        by Hallow ( 2706 )
        Ah, but that leads to another problem in typical Judeo-Christian theology/philosophy. If G. existed before the universe, the G. exists outside the universe. If G. exists outside the universe, then the universe could act on G., making G. not perfect.

        I'm much more inclined to agree with Spinoza -- basically that the universe is G., that G. is infinite in space as well as time (forward and backword), and G. doesn't decide anything, G. simply "is". Most Judeo-Christians really don't like this because it means that man is actually *part* of G., and that all the "evil" in the world is part of G. too, and that all the "mythological" type stuff (such as creation) in the Judeo-Christian world wouldn't work (especially if G. aka the universe has always existed).

        When Einstein was asked by a reporter if he believed in G., he said he believed in Spinoza's G.

        I'd highly recommend Spinoza's Ethics [mtsu.edu] to anyone who wants to know more.
        • If G. exists outside the universe, then the universe could act on G., making G. not perfect.

          That is an interesting way to think about it (and I agree to some extent with Spinzoa's ideas,) but I'm not sure the above statement makes sense. The universe *could* act on God if God exists outside the universe, but that doesn't mean it does... so it doesn't speak to whether God is perfect or not.

        • Re:Uh oh... (Score:2, Insightful)

          by SkorpiXx ( 567249 )
          Reply to Hallow: There is a slight problem in your logic. If God created the universe, then he is not constrained by it. Since God made the universe, then He controls it, not the other way around. Your break in logic was not assuming that God coincided with the universe--outside of it. Judeo/Christian theology states that God created the Heavens and the Earth... which is the Universe. Since He created it, he encompasses it... omnipresent, by definition. But He is not constrained by the Universe, because He exists outside of the Universe whilst inside of it, watching over us. I'd highly recommend The Bible to anyone who wants to know more.
        • "If G. exists outside the universe, then the universe could act on G., making G. not perfect."

          Just how do you come to that conclusion, that's ridiculous. There is absolutely no basis for that statement at all, you simply pulled it out of your ass.

          That's like saying, "If God ('G.', wtf?) exists outside the universe, he probably eats a lot of *waffles.'

          * I just said "waffles" because I've had a craving lately, but I never get to eat waffles...

    • Re:Uh oh... (Score:5, Insightful)

      by slackerweb ( 313212 ) on Sunday May 05, 2002 @01:41PM (#3466077)
      The big bang or any other theory of the universe does not contradict the existance of God, it only contradicts their narrow-minded view of God.
      • That is one of the most excellent statements I have ever seen on Slashdot. Very nice.

      • Re:Uh oh... (Score:3, Insightful)

        by An Onerous Coward ( 222037 )
        Why is it that so many people think I'm insane for not believing in God, yet don't mind that they believe in a God that they can't seem to tell me anything about?

        For thousands of years, the devout managed to convince people that the Bible was the literal Word of God. Then we found some stuff out about the world that didn't line up with the claims made by the Bible. So now different religious groups are either telling us that science is wrong, or telling us that it doesn't matter.

        I can actually fathom the conservative viewpoint better. I mean, at least there's a weird logic to their position. But liberal religions don't seem to mind jettisoning things like a literal seven day creation, a literal Noah's Ark, and even a literal Resurrection. I understand why someone would give up on such apparent absurdities, but why continue to worship the vacuous concepts that remain?

        It's impossible to just talk about "the existence of God" without explaining the nature of the thing being discussed. A conception of God that is "wide-minded" enough to adapt to any sort of evidence that science might present in the future cannot be informative enough to be compelling. If you're going to believe in God without believing anything in particular about God, why not just be an agnostic and be done with it?
        • It's impossible to just talk about "the existence of God" without explaining the nature of the thing being discussed

          Why is that? Science relies heavily on the concept of infinity, and it has no nature to be discussed. There are many mathematical properties that involve it, yet do those express its true nature? Why does discussing God have to involve any particular nature? That seems very narrow minded to me (in the literal sense.)

          • Re:Uh oh... (Score:2, Informative)

            by Darby ( 84953 )
            Why is that? Science relies heavily on the concept of infinity, and it has no nature to be discussed. There are many mathematical properties that involve it, yet do those express its true nature?

            Infinity was unclear once upon a time, but not any more.
            Largely through the work of Georg Cantor, the nature and properties of infinity have been absolutely described.
            There was a time when this was unclear and this bothered people. So they went ahead and cleared up the ambiguities.
            While this doesn't give a definitive answr to the issue in question, your example did just turn around and bite you on the ass.

        • No - you are wrong. The "bible" is a bastardized version of verbal (transcribed later) stories. Those stories were likely written down by someone (likely a woman says the experts) years after the stories happened. Christians came along, fucked the whole thing up, changed the stories to fit their own idea (to gain political control), and further bastardize religion today.

          Of course there are things which YOU may not believe but may have actually happened. The "seven day theory" isn't in scientific terms seven days at all. If you look at the age of the universe - a guess at this point - and look at everytime it expands to double it's size that would be one day. Of course we think one day around the Sun, but to a God that would be all knowing or powerful one day wouldn't mean anything to him/her/it. Maybe it's just easier to explain these things to idiot humans in simple terms.

          Simply - Occam is a fag. It's quite parsimonious for you to say that there is no evidence. It's easy for the human mind to say there is no evidence and move on. The idea of God is one that says there is a being, a spirit or intelligence that we can not see. The idea of God is one that says we couldn't comprehend the idea of it.

          We can't even explain the universe we do see. We can't imagine the size of it. There are so many theories in Quantum Phyics alone that suggest an idea of God because of interactions on the sub-partical level.

          Shit... you can give me reasons that God doesn't exist but you can't even support some of the science that claims it doesn't.

          If you don't believe why bother trying to convince people that it doesn't exist? Put your effort towards science only. The claims made about science from the "Church" (you know who I mean) were all made because they were afraid that they would loose control. This is why you have a problem with people who believe - you want them in your camp. Why bother?

      • Re:Uh oh... (Score:3, Interesting)

        by ImaLamer ( 260199 )
        Correct. The current theory contradicts the dumbed down - King James version of what happened. (?)

        There is a book by a Rabbi which lays out the age of the universe, and it's expansion, compared with the seven day theory. His theory concludes that we are still in the 6th day and approaching the 7th.

        I guess that we could say that the 7th day will be when the whole thing implodes and he gets to rest.

        In all reality the idea that God could have worked through the big bang isn't a bad one. Where things get sticky is when we start talking "life". ( Actually evolutionary timelines fit the same scale - the rise of humans is an example. Even the age of the Earth and the times which the skies cleared so that light could be visible from that early primordial Earth fit )

        I think where we have all gotten into trouble isn't when we fight over IF God exists - the problems start when we try to measure why's and how's. We start to make crazy claims that we are alone, but I haven't found the backing for this at all. There is a whole list of topics that we try to say this or that about but we have no clue.

        If (a) God exists we shouldn't try to fit our narrow view into his/her dimension of reality. For all we know he/she/it sits down and writes our DNA with an old feather plume, selecting which genes go and which stay. Of course this is in the lines of "Design" theories of life and I don't personally believe that....

        The point is that we can only know what science tells us and our religions suggest. If we try to combine the two we walk on shady ground.

    • Re:Uh oh... (Score:3, Interesting)

      by nil5 ( 538942 )
      Science is the pursuit of truth about the world around us. There is not a necessary reason for it to be at odds with religion, because what it finds is the truth to the best of our ability to reason. It really is not about science contradicting what your religion dictates, because if you are truly religious, your faith will not be swayed by what some scientist has to say about creation.

      My belief is that God, being all powerful and infinite and inconceivable in the minds of men, could certainly create all the universe and all its laws and properties in any way. So, if one has any faith in God or His omnipotence, he/she shouldn't be discouraged by new theories of science that seem to contradict His existence.

      For the simple minded, think of it like this: if you were a divinity, wouldn't you be able to make it seem as though you don't exist to test the faith of those who are less powerful?

      A Christian example is when Christ appeared to the apostles, all except Thomas. Thomas didn't believe that He had risen from the dead. Later when Christ appeared to him, he said, "blessed are you who have not seen and yet still believe."

      So, the final answer for a religious person in any case like this is the single word "faith". Science isn't going to get in my or anyone else's way.

    • Re:Uh oh... (Score:2, Insightful)

      by pkplex ( 535744 )
      According to the Bible, God created the earth and life on it in 6 days, not 7. God rested on the 7th day. There are also things written in the Bible about time in relation to God: "But, beloved, be not ignorant of this one thing, that one day is with the Lord as a thousand years, and a thousand years as one day" 2 John 3:8. This suggests that god is external to and not affected by the 'dimension' called time.
    • (* This one might piss off the religious right. The Big Bang could sort of be reconciled with the idea that God created the world in 7 days, since maybe the Big Bang happened on the first day. But the idea that the universe has always existed (and therefore predates creation) is a big problem, since it excludes God from the picture. *)

      The savior (pun) is that it can be interpreted many ways. "Creating the heavens" could mean the birth of the solar system, the birth of our galaxy, etc.

      The vast majority of what we see in the sky with the unaided eye is in our own galaxy. Thus, it could be argued that "the heavens" is a lay man's way of translating Milky Way Galaxy.

      IOW, the scope of the creation story is not clearly stated.

    • As a straight Bible-believing, Christian creationist, I do not feel at all threatened by this theory that the universe is cyclic. Nor does the idea of the big bang theory threaten me in any way, because I don't believe either of them.

      That said, I also don't value religion over science or believe they are at odds. Obviously, if an omnipotent God created the world from nothing he set up the rules by which it would be governed.

      Really, I see this situation as a case of a theory on something we know practically nothing about coming up to challenge a more commonly held theory about something we know practically nothing about.

      As a six-day creationist, will I be any more wrong in the long run than all big-bangers out there if the cyclic theory turns out to be true? Or what about the next big origins theory?

      Science is supposed to be observable, measurable, and repeatable, but when we're talking origins, particularly universal origins, one really doesn't have that evidence to support one's ideas. All we really have is what we can observe right now, subject to human interpretation, and we have to use that data to project back some huge amount of time. I've always been told in my engineering classes that it is very dangerous to project your data out farther than you have measured, so that doesn't exactly reassure me about these theories.

      Well, I've been interrupted by more than one excessively long phone calls while writing this, and I've completely lost my train of thought, so I guess I'll just post this as the rambling mess it is.

      I would be interested to hear if there are any die-hard big-bang people who have problems with this new theory.

    • BTW days in the Bible are often used to refer to periods of time. The 6 creative days could have added up to billions of years, and based on the age of the earth I'd say they did.

    • Re:Uh oh... (Score:3, Interesting)

      by Christianfreak ( 100697 )
      God is great and he can create things anyway he wants to.

      That said, why is it that everytime there is an article on /. that has anything to do Evolution/Big Bang, beginning of the world kinds of things that people who aren't religious drag religion into the discussion?

      Most religious people (most not all) can think. Most of them don't really care how the world began because they realize that the Bible book of Genesis doesn't give a scientific explaination of the beginning of the world. Rather boiled down into a nutshell it says that the world is here and God is responsible for that. So whether its been here for 200 years or 200 trillion really doesn't matter, whether God spoke or if he caused the processes we see today, it really doesn't matter.

      Now there are some people who believe it happened like the Bible describes. Which is okay too. Because just like everyone else at least in the US they have the freedom of speech. And they can say what they want.

      So much for mod points :)

  • Obligatory Simpsons Quote (Score:5, Funny)

    by Roosey ( 465478 ) on Sunday May 05, 2002 @01:10PM (#3465975)
    "Your idea of a donut-shaped universe intrigues me Homer; I may have to steal it." - Stephen Hawking

    Sorry, I had to do it. :]

    • Simpsons quote actually appropriate (Score:5, Interesting)

      by wass ( 72082 ) on Sunday May 05, 2002 @02:12PM (#3466181)
      Actually, that quote is more appropriate than you might think. One of the physicists quoted in the article, Dr. Paul Steinhardt, was my professor in a graduate-level cosmology class I took in college about 6 years ago. This was when Steinhardt was still teaching at University of Pennsylvania, before he moved to Princeton.

      Anyway, it turns out that Steinhardt, when he was a grad student decades ago, either published or was on the verge of publishing a paper on some theory of inflation or other. Dammit, but I can't remember exactly what the theory was right now. Anyway, Stephen Hawking accused Steinhardt of stealing his own idea. Steinhardt was at a critical moment, because being a graduate student accused of plagiarism or idea-theft, he could serious problems with his advisors and future co-workers.

      The original printing of Brief History of Time even referred to Steinhardt as stealing Hawking's theory. Hawking narrowed down the 'theft' to a talk he gave, I believe at Drexel University. What Steinhardt was able to do to redeem himself was to obtain a video recording of the Drexel talk and prove that Hawking didn't mention that theory anywhere in the talk.

      The result is that the community now recognizes Steinhardt's genuinity in the matter, and Brief History of Time has been revised. It now only alludes to a copying of idea, instead of outright accusation, by saying something like "in a suspicious circumstance, a similar theory was published on the east coast at the same time" or something like that.

      Brief mention of this is in the 4th paragraph of this link [geocities.com].

  • Experimentally tested? (Score:3, Funny)

    by mikosullivan ( 320993 ) <miko@idocCOUGARs.com minus cat> on Sunday May 05, 2002 @01:12PM (#3465980)
    ... could be experimentally tested in the coming years

    Ah, so that's how new universes come into being.

  • Paper abstract (Score:3, Informative)

    by pq ( 42856 ) <rfc2324&yahoo,com> on Sunday May 05, 2002 @01:14PM (#3465985) Homepage
    This paper appeared on astro-ph last week, as astro-ph/0204479 [arxiv.org]. Here's the abstract:

    The Cyclic Universe: An Informal Introduction
    Authors: Paul J. Steinhardt, Neil Turok

    The Cyclic Model is a radical, new cosmological scenario which proposes that the Universe undergoes an endless sequence of epochs which begin with a `big bang' and end in a `big crunch.' When the Universe bounces from contraction to re-expansion, the temperature and density remain finite. The model does not include a period of rapid inflation, yet it reproduces all of the successful predictions of standard big bang and inflationary cosmology. We point out numerous novel elements that have not been used previously which may open the door to further alternative cosmologies. Although the model is motivated by M-theory, branes and extra-dimensions, here we show that the scenario can be described almost entirely in terms of conventional 4d field theory and 4d cosmology.

    In spite of the "informal" claim, the paper is fairly dense - IAAPA (I am a professional astronomer) and I found it heavy going. But the link above has PDF versions if you're interested.

    • " The Cyclic Model is a radical, new cosmological scenario which proposes that the Universe undergoes an endless sequence of epochs"

      Whatever else this model is it's neither new nor radical. It's actually a re-statement of Hindu mythology which has been around for thousands of years. It would be funny though is a six thousand year old myth did indeed describe the universe correctly.

  • In other news.... (Score:5, Funny)

    by Linuxthess ( 529239 ) on Sunday May 05, 2002 @01:21PM (#3466016) Journal
    Milliways, The Restaurant at the End of the Universe closed its doors in protest. Max Quordlpleen was quoted as saying "I just came from the other End of Time, where I've been hosting a show at the Big Bang Burger Bar. This is all just a shallow attempt to discredit me, and my patrons."

    --------

    • That's not funny! My dog, Puggles, died in a universe collapse. How can you make light of such events?

      Rest in Peace, dear friend Puggles.

      [de5jdk7635uyt237]

  • More Information (Score:2, Informative)

    by jaywhy ( 567133 )
    Some more info on,

    http://feynman.princeton.edu/~steinh/

  • A little more sense (Score:2, Interesting)

    by pkplex ( 535744 )
    "A new theory of the universe suggests that space and time may not have begun in a big bang, but may have always existed"

    To my line of thinking, it is totally illogical for this massive place this earth is floating around in, to have exploded out of nothing... and then _somehow_ created the amazing order we are able to observe thruout our window and in our linux boxes.
  • The latest versions of the big bang theory, with the addition of dark energy or whatever, of an extra repulsive force, predict, basically, the entropic death of everything - the universe as we know it today, with hot stars and habitable planets and the like, exists for some finite period and then disperses forever.

    There is certainly a desire - I feel it, myself - that the universe not be that way. It is far more pleasant to think that it will regenerate itself and that complex phenomena like life could re-emerge in some subsequent cycle. However, it is important, as scientists, that we not give in to wishful thinking of that sort.

    While these branes are a cute idea in a number of respects - not just because a parallel plane full of dark matter is 100% cool old school science fiction - it strikes me that they answer "how can we match our observations to what we want to be true?" rather than "how can we match our explanations to what we observe?"

    Which is not to say that it isn't an excellent theory - merely that there is extreme intellectual danger associated this sort of speculation.

    Let me say also - Entropy is a thorough bitch. Whatever the laws of physics turn out to be, and whatever cycles they may allow, if subsequent phenomena depend in any way on previous phenomena (phenomena being the most general term I can manage), there will be a tendency for the whole shebang to degenerate, to move into a more likely state. It is possible that the most likely state for the whole universe involves repeated regeneration of galaxy-rich explosions like the one we all inhabit, but it is also possible that subsequent big bangs would be smaller and smaller in size, eventually dwindling below some critical threshold to generate stars and the like.

    • While these branes are a cute idea in a number of respects - not just because a parallel plane full of dark matter is 100% cool old school science fiction - it strikes me that they answer "how can we match our observations to what we want to be true?" rather than "how can we match our explanations to what we observe?"

      Which is not to say that it isn't an excellent theory - merely that there is extreme intellectual danger associated this sort of speculation.

      I think that you are overly restrictive in your requirements of how we generate our theories. Really, there should be absolutely no constraints on how we generate our theories. Theory generation may be driven by observation or driven by the fantasies of a madman---it doesn't matter. In the end, all theories have to stand up to experimental scrutiny, irrespective of how they were generated.

      After all, even Einstein was driven by need for beauty when he came up with General Relativity. By your standards he definitely was working in an intellectual danger zone. In fact, I would prefer theorists operate in the danger zone more often than they currently do.

      • Theory generation may be driven by observation or driven by the fantasies of a madman---it doesn't matter.

        He was referring specifically to a scientist's method, not his motivation. Discarding hard evidence because it's incompatible with one's hopes/expectations is downright wrong.
    • I got the same uneasy feeling about wishful thinking. Even the most optimistic physicists began to admit that accelerating expansion data probably means that immortality (having infinitely many thoughts) is impossible. Now they may have a new source of hope! (Actually, I think not.)



      I know that this new theory isn't exactly like the "big crunch" which noone believes in anymore. There was a time when Hawking thought the big crunch meant that the second law would run backwards, and that order would emerge out of disorder. However, he gave that up while many people still held out the big crunch as a possibility, because it turns out that the universe can crunch together without violating the second law.


      So, if this new speculative theory is true, it might just be that the universe is inflating and deflating in a periodic manner. It does not mean, however, that entropy decreases in the deflation stages. I wish someone who knows more about this could say whether this theory is consistent with the sort of "oscilation heat death" where in each cycle of oscilation, energy gets more evenly spread out until all matter and structure is dissolved?

    • Entropy is a thorough bitch. Whatever the laws of physics turn out to be, and whatever cycles they may allow, if subsequent phenomena depend in any way on previous phenomena there will be a tendency for the whole shebang to degenerate, to move into a more likely state.
      Try this: While entropy is indeed happening, something else is happening at the same time and because/causal of it: the `low-grade' energy predicted is more organized. This increased level of organization happening in parallel with entropy may metaphorically be similar to the `branes' mentioned. Nevertheless, although I agree that this hypothesis is not (yet) compelling and may not be well-founded, I feel it is more nearly accurate than the `big bang' booshwa we've been handed.
      • The point I am trying to make is that Entropy isn't really about order or disorder, that's what we observe, it is really about PROBABILITY. Whatever sort of system you have, if it is becoming more ordered, if it is becoming less, if it is undergoing two different sorts of totally different mathematical transformations at the same time, will move from whatever state it occupies to the state of maximum likelihood. In the universe that we observe on a day to day basis, the state of maximum likelihood is disordered; it has a maximal number of microstates available to it. EVEN IF THAT IS NOT THE CASE - even if the state of maximum likelihood conforms to some other property - there is still a tendency to move towards it!

        Once it is reached, there is no tendency to leave it.

        If the motion from a less likely state to a more likely state is what drives the repeated generation of big bangs - and it is what drives *everything else that we have ever observed* - eventually it will run down and new big bangs will no longer be generated.
    • While these branes are a cute idea in a number of respects - not just because a parallel plane full of dark matter is 100% cool old school science fiction - it strikes me that they answer "how can we match our observations to what we want to be true?" rather than "how can we match our explanations to what we observe?"

      Actually, I just took a seminar on Visualizing Higher Dimensions and one of the last thing we covered was the idea of M-theory or string theory. Specificially, the idea that there's another "universe" full of dark matter, which accounts for all the extra mass we can't see. And rather than it being far away, it's right next to us, a distance about 1x10^19 times smaller than the nucleus of an atom.

      If you've ever noticed how a squirrel manages to stay on the exact opposite side of a tree when you chase it, the idea's the same. That "universe" is just on the other side of space-time, and no matter which way we move, we can't see it, 'cause it's always on the opposite side. Perhaps that's where anti-matter comes from. Who knows.

      Anyway. AFAIR, I think that Stephen Hawking proposed something similar for his phD thesis, except more along the lines of: "The universe will eventually stop expanding, collapse, and re-big-bang." So cyclic theories are not new.

      So the branes might be a "cute idea" to you, but they might also be right. The important thing is to keep your mind open about what possibilies there are, and not just focus on what "feels right" or wrong. :)
    • Let me say also - Entropy is a thorough bitch.

      Entropy, huh? My ex-girlfriend told me her name was Diane, that bitch!
    • Let me say also - Entropy is a thorough bitch.

      Entropy, huh? And my ex-girlfriend always told me her name was Diane!
    • From the article:
      It addresses, for example, the nagging question of what might have triggered or come "before" the beginning of time.

      I too wonder if there is some wishful thinking in there. It does not make the theory any less valid but many scientists don't like the lack of closure with the Big Bang Theory. The Big Bang Theory has some philosophical implications of a creator (or creating process) that does not fit nicely in the philosophical belief of Naturalism. This theory fits better with that Naturalistic belief. I suspect that many scientists will adopt this theory because of its Naturalistic implications, and that it the concern over the old Big Bang proponents squashing it will be misplaced. There will be 2 strong competing theories in the future.

    • The acceleration of the expansion actually cools the universe, so the high-entropy 'heat death' is avoided; it is more akin to a 'big freeze'. Any collection of matter that is not gravitationally bound together will eventually be spreading apart faster than light (i.e. intervening space stretches faster) and will be forever out of reach. The increasing entropy, smoothing out of energy density variation, will be limited to local areas, where by local I mean that it is not stretching faster than light so that energy transfer can occur throughout the locality. Of course, life is still f*cked because it can't reach the other areas and use the energy difference to do work (unless faster than light travel is discovered).
    • "The latest versions of the big bang theory, with the addition of dark energy or whatever, of an extra repulsive force, predict, basically, the entropic death of everything - the universe as we know it today, with hot stars and habitable planets and the like, exists for some finite period and then disperses forever."

      The heat death of the universe is something I rank up with the Big Crunch and the sun going nova. These are things that, if humanity is still around at that point, I'm confident we'll have a solution figured out by then.
    • "if subsequent phenomena depend in any way on previous phenomena (phenomena being the most general term I can manage), there will be a tendency for the whole shebang to degenerate,"

      But if it doesn't depends on the preceding occurences, there is no way to say that anything has any influence on anything else and everything "just happens." You reading this text isn't effecting the thoughts in your mind, they "just happen" to be happening at the same (or however it looks in your relativistic frame of reference).

      Maybe I need to read up on entropy more, but it seems that there's an inherent flaw in trying to go back to exactly the way things were in the beginning of the cycle becasue you're only resetting three dimensions.

  • Well, this just makes sense (Score:2, Funny)

    by Anonymous Coward
    After a big bang, lots of people need to wait a while before they can go again.
  • Strangely, this seems to be more in keeping with some of the things you can find in certain far eastern writings. Alot of folks will get their jollies out of this, ie, "See, I told you so!"

    Personally, I always like the idea of another structure operating at another order of magnitude beyond what was observable.

    Some folks think that such a cyclic universe would be literally repeating, which is plain silliness in my mind. It is not the big rewind button in the sky, so far as I can see.

  • Sky and Telescope [skyandtelescope.com] also covered this story, but didn't obscure it with piss-poor scientific writing like this other source did.

    As an aside, the other source over simplifies things, and leaves you with the feeling that you learned nothing but marketing hype. It's target is obviously non-astronomers (or we would have read the original paper in an original journal.) Because of that, they should have explained "branes" (and other terms) with more than sound-bytes from involved physicists. Think diagrams, break-out boxes, etc.

  • It's really weird that I was telling out of nowhere, I was thinking of this theory while having a beer with my girlfriend. I told her this and she thought I was crazy!

    Anyways, what I had explained was that there will come a time when the universe goes back to the beginning. At that point, the entire civilization will start anew. However, there will be certain people that will "remember" their previous life in the previous cycle. These people will go on to spread the "truth" which will turn into modern day religion. People like Jesus, Mohammad, Tao te Ting, etc .. the prophets are just people that remember the mistakes of the prior universe, the problems with mankind and how it results into the cycle of the universe. Budhist teaching talks a lot about cycles in that you want to break out of the cycle and achieve enlightenment. Other people like Nostradamus also "remember" the events of the prior universe and go off to "predict" it and write about it. At the bookstore the other day, I was skimming through a book called Bible Codes; it's about how modern events are predicted in the Hebrew bible.

    Anyways...that's just my little theory...
    • No-one said that the same universe comes out again- it's a different universe. Well, that's how I read the article anyway, but who gives a toss, because it's all a load of unscientific crap anyway.

      graspee

    • I'd suggest to you to look into Hank Wesselman's books. ( http://www.sharedwisdom.com/ ) Although they go somewhat into the reality of fiction they could be true. The reason I point this out is that there are many points that you may agree on.

      The books do contain plenty of fact, and some that could support your idea.

      I personally believe in God, but in a different way than many do. If you look into the bible (actually the torah-damn christians!) you learn that God was known before Abraham, but not followed until he choose to speak up. I think that God is all knowing and everywhere. No matter what happens to us God will still exist, and if the Universe collapses then God will still be there playing around. Maybe if we break out of our cycles and become enlightened then we can stop the cyclic idea. Maybe God will stop it? (hey, it's just a thought)

      You must remember that the people you mentioned like Jesus (yuck), Mohammad, Buddha, and Abraham were prophets. They likely got their information from that source we know as God.

      Occam's a fag so don't bother responding with that crap slashdotters. (if the simple answer is what you want why bother with advanced quantum theory etc?)

  • The Last Question (Score:3, Interesting)

    by blixel ( 158224 ) on Sunday May 05, 2002 @02:24PM (#3466222)
    "The Last Question" by Isaac Asimov.

    The story begins in the year 2061, when a colossal computer has solved the earth's energy problems by designing a massive solar satellite in space that can beam the sun's energy back to earth. The AC (analog computer) is so large and advanced that its technicians have only the vaguest idea of how it operates. On a $5 bet, two drunken technicians ask the computer whether the sun's eventual death can be avoided or, for that matter, whether the universe must inevitably die. After quietly mulling over this question, the AC (analog computer) responds: "Insufficient data for a meaningful answer."

    Centuries into the future, the AC has solved the problem of hyperspace travel, and humans begin colonizing thousands of star systems. The AC is so large that it occupies several hundred square miles on each planet and so complex that it maintains and services itself. A young family is rocketing through hyperspace, unerringly guided by the AC, in search of a new star system to colonize. When the father casually mentions that the stars must eventually die, the children become hysterical. "Don't let the stars die," plead the children. To calm the children, he asks the AC if entropy can be reversed. "See," reassures the father, reading the AC's response, the AC can solve everything. He comforts them by saying, "It will take care of everything when the time comes, so don't worry." He never tells the children that the AC actually prints out: "Insufficient data for a meaningful answer."

    Thousands of years into the future, the Galaxy itself has been colonized. The AC has solved the problem of immortality and harnesses the energy of the Galaxy, but must find new galaxies for colonization. The AC is so complex that it is long past the point where anyone understands how it works. It continually redesings and improves its own circuits. Two members of the Galactic Council, each hundreds of years old, debate the urgent question of finding new galactic energy sources, and wonder if the universe itself is running down. Can entropy be reversed? they ask. The AC responds: "Insufficient data for a meaningful answer."

    Millions of years into the future, humanity has spread across the uncountable galaxies of the universe. The AC has solved the problem of releasing the mind from the body, and human minds are free to explore the vastness of millions of galaxies, with their bodies safely stored on some long forgotten planet. Two minds accidentally meet each other in outer space, and casually wonder where among the uncountable galaxies humans originated. The AC, which is now so large that most of it has to be housed in hyperspace, responds by instantly transporting them to an obscure galaxy. They are disappointed. The galaxy is so ordinary, like millions of other galaxies, and the original star has long since died. The two minds become anxious because billions of stars in the heavens are slowly meeting the same fate. The two minds ask, can the death of the universe itself be avoided? From hyperspace, the AC responds: "Insufficient data for a meaningful answer."

    Billions of years into the future, humanity consists of a trillion, trillion, trillion immortal bodies, each cared for by automatons. Humanity's collective mind, which is free to roam anywhere in the universe at will, eventually fuses into a single mind, which in turn fuses with the AC itself. It no longer makes sense to ask what the AC is made of or where in hyperspace it really is. "The universe is dying," thinks Man, collecitvely. One by one, as the stars and galaxies cease to generate energy, temperatures throughout the universe approach absolute zero. Man desperately asks if the cold and darkness slowly engulfing the galaxies mean its eventual death. From hyperspace, the AC answers: "Insufficient data for a meaningful answer."

    When Man asks the AC to collect the necessary data, it responds: "I will do so. I have been doing so for a hundred billion years. My predecessors have been asked this question many times. All the data I have remains insufficient."

    A timeless interval passes, and the universe has finally reached its ultimate death. From hyperspace, the AC spends an eternity collecting data and contemplating the final question. At last, the AC disovers the solution, even though there is no longer anyone to give the answer. The AC carefully formulates a program, and then begins the process of reversing Chaos. It collects cold, interstellar gas, brings together the dead stars, until a gigantic ball is created.

    Then, when its labors are done, from hyperspace the AC thunders: "Let their be light!" and there was light.

    • The AC (analog computer) is so large and advanced that its technicians have only the vaguest idea of how it operates.

      So it's kind of like a Microsoft operating system, is it?

      Makes sense that when the Universe blue-screens at the End of Time, you can just reboot it and the Universe will come back online (though you'll have lost all the work and have to start over)
    • Huh? How come the AC wasn't destroyed at the heat death of the universe? And if the answer is that it was in "hyperspace" why didn't the people just go hang out in hyperspace? Sheesh!

      Otherwise, a neat story!

  • I love how all these new theories are "O so much better" than the Big Bang theory. Oftentimes they cite how this new theory takes into account all of these interesting phenomena which the Big Bang theory does not, or does with this additional theory...

    It reminds me of how some programmers wish to totally rewrite a program with a different design, stating that the new design will take into account all of the issues which were fixed with patches in the other program.

    Well, if this new theory (program) DIDN'T take those phenomena (bugs) into consideration, the theory (program) wouldn't even be considered....

    Hindsight is 20/20.

  • Steven Weinberg (Score:5, Informative)

    by polyphemus-blinder ( 540915 ) on Sunday May 05, 2002 @02:48PM (#3466314)
    Okay, a lot of people have been saying that an infinite cycle of exands and contracts would NOT generate infinite heat. Here's what Steven Weinberg has to say:

    "Some cosmologists are philosophically attracted to the oscillating model, especially because, like the steady-state model, it nicely avoids the problem of Genesis. It does, however, face one severe theoretical difficulty. In each cycle the ratio of photons to nuclear particles (entropy per nuclear particle) is slightly increased by a kind of friction (known as "bulk viscosity") as the universe expands and contracts. As far as we know, the universe would then start each new cycle with a new, slightly larger ratio of photons to nuclear particles. Right now this ratio is large, but not infinite, so it is hard to see how the universe could have previously experienced an infinite number of cycles."

    Pysicist Sidney A. Bludman says:

    "Our Universe cannot bounce in the future. Closed Friedman universes were once called oscillatory universes. We now appreciate that, because of the huge entropy genereated in our Universe, far from oscillating, a closed universe can only go through one cycle of expansion and contraction. Whether closed or open, reversing or monotonically expanding, the severely irreversible phase transitions give the Universe a definite beginning, middle and end."

    If any of you have counter-quotations from equally famous physicists, I would love to read them. This is all I have found on the matter so far.

  • Is this really new? I don't know where I first heard it, but I know that a "big crunch" has certainly been theorized. I've always thought that it seems likely that a big crunch might cause a big bang to follow. I don't know, maybe I was assuming something.

    Be that as it may, one perhaps unusual bit of evidence I've always thought in favor of a cyclic universe is the existence of intelligence life on Earth. First of all, I'm pretty much of the belief that intelligent life is hugely, extremely, unbelievably unlikely. I have a feeling that if we inventoried the universe, we would find a small proportion of single cell life, some but almost nonexistent multicellular life, and higher life forms totally absent except for us.

    If you look at the complexity of human beings, it's just crazy how many things have to go right to get intelligence. I mean, it took 2-3 BILLION years just to get us, and no other animal form is even close to us.

    When you combine that with the fact that it only takes 2-3 million years to fill a galaxy once you have intelligent life even at sub-light speeds, that means it's probably never happened before in this galaxy.

    So given that intelligence almost never happens, and it took about 1/7th - 1/4th the age of universe for it to happen here, I think that gives evidence that we needed a hell of a lot of universe cycles to get it to happen.

    • No not at all new.

      There have been theories about cyclic expansions and contractions lasting say a 100 billion years. But these theories were killed by the realisation that there was not enough mass in the universe to reverse the contraction.

      Also there is a class of theories, which I guess this theory belongs to where the universe reproduces itself. Scientific American had an article on this about 10 years ago. About how after a very long period of time the universe could spontaneously generate a new big bang withough contraction.

      In fact, an update on the original article can be found here [sciam.com].

      As you can see this looks a lot like the current theory at first sight, but they are quite different since the latest one involves 'branes'.

    • Completely different (Score:4, Informative)

      by coyote-san ( 38515 ) on Sunday May 05, 2002 @05:51PM (#3467026)
      While there's a superficial resemblence, there's a huge difference between the old oscillatory models and this one.

      In the old models, the universe collapsed from many billions of light years across (or even larger - we really have no idea of how big the universe is) back to the singularity of the big bang.

      In this model, the universes (plural) only have to move a few millimeters. The big bang occurs when the branes separate (we're in one brane, the other universe is in another), and the big crunch occurs when they collapse again. The point of intersection can even travel faster than the speed of light without violating relativity - it's okin to the scan of a lighthouse beam against a wall a very long distance away.
    • "Is this really new? I don't know where I first heard it, but I know that a "big crunch" has certainly been theorized. I've always thought that it seems likely that a big crunch might cause a big bang to follow. I don't know, maybe I was assuming something."

      A few years ago I tried tackling The Elegant Universe (string theory and such). I remember reading that one of the fundamental parts of string theory is the idea that distance (space-time) is quantized (much like energy) and there is a lower limit to how close two things can be, and when you try to bring them closer you actually bring them further apart (what did you expect? It's partly quantum mechanics!). One of the examples given was that how a potential Big Crunch would shrink the universe to a smaller and smaller size until it reaches this finite limit and the very forces that are contracting the universe end up expanding it again.

      If this turns out to be the case, concepts like "Big Bang" and "Big Crunch" could end up being meaningless, or at least synonyms.
    • I'm not too sure I agree with you on the odds of intelligent life existing elsewhere in the universe, but one good thing I can say about your opinion is that IF indeed we're so unique, that then more than ever we should all think about ways to extend self-awareness beings all over the universe. Who knows, maybe we're the first and only intelligent beings in this universe, so why not take on the responsibility to take such a beautiful thing and make it blosson all over the universe?
  • Postulating a big bang to explain red shift has always seemed particularly unimaginative to me. But that's besides the point. I still believe that theorizing about the beginning of universe is pointless and will remain pointless in times to come (pun most definitely intended), because we observe a local region, and while our definition of local will change as we learn more, we will still only see a local region, dammit!

    Properties of local regions differ tremendously (from the real picture) in the Universe, as all the classical physicists found out, much to their dismay, in the early 20th century. I am pretty sure, more advanced civilizations around the universe have written it off as the NP-hard problem of all times.

    Existence exists; deal with it. :-)

  • Those who promote the cyclic-universe theory, shall hereby be called cyclists. The conventional way of seeing the universe is just a lot more pedestrian.
  • If the show Lexx, with it's concept of time existing in cycles that happen over and over again, is proven to be the most scientifically realistic sci-fi show ever, imagine what other stuff from the show could be true...(shiver!)
  • You know, it seems that the weirder the theories, the weirder the supplanting theories.

    Rather than actually make sense, these theories get weirder, stranger, more incomprehensible, and more imaginative with each cycle.

    Pretty soon, they'll be talking about the "archangel" as though he/she/it were proven!

    Perhaps, rather than looking at the "cyclical theory of the universe" we should be looking at the "cyclical view of universe theory"?

  • That the world is not going to end in my lifetime.....
  • "Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." --Albert Einstein

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