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Post by humphreyclarke on Jun 2, 2008 10:44:01 GMT
Hi all I thought I should ‘christen’ this part of a forum with a topic about the multiverse. Are you as theists, or atheists/agnostics against it? Those of you who are theists might be interested to know that this topic did come up during the Middle Ages when some clerics asked whether god could create more than one universe or whether he/she/it would be happy sticking with one. In the event the Bishop of Paris intervened and said that yes, God could create as many universes as he wanted and there the matter was settled. Some chap called John of Vassals later said that god could create an infinite universe provided that it was not too infinite as this would be tantamount to creating another god. Thomas Bradwardine on the other hand (who later became archbishop of Canterbury) insisted that the universe was has to be infinite because god is infinite and exists in the universe. With the advent of the ‘fine tuning’ problem and the sudden appearance of speculative multiverses amongst the scientific intelligentsia, all that talk during the so called dark ages suddenly looks very far sighted. Personally I’m set against the idea but I do see any reason why a theist should take this position. Here are some thought of mine on the matter. 1) Although the multiverse idea is increasingly accepted because of the theistic overtones of fine-tuning (notably by Richard Dawkins in the God Delusion) the sheer metaphysical silliness of the idea is rarely discussed (although see Marcus Chown’s article www.telegraph.co.uk/connected/main.jhtml?xml=/connected/2007/01/16/ecelvis116.xml) . We can infer from the fact that this multiverse produced our universe that the great universe replicator can make more like this one and if the multiverse is infinite or pretty close to infinite, as it is in most models (see Tegmark) then anything that can exist does exist, including of course God!. See Paul Davies book ‘The Goldilocks Enigma’ where at one point he concludes it is more likely we are living in a simulated universe, at which point one is tempted to reach for Occum’s razor and begin slashing away like Norman Bates. 2) As Prof George Ellis has pointed out, even if there is a multiverse we still have to ask ‘why this multiverse?’ as there are plenty of types of multiverse that wouldn’t have a chance of producing life because they would lack the right properties (e.g one that doesn’t produce chaotic inflation) 3) As Roger Penrose has noted, you don’t need that much order to produce life. Conceivably the most common type of life producing universe in the multiverse would be one in which chaos is predominant and in which life would flukely emerge in a ordered corner. We don’t see that, instead we see order as far as our eyes can see. In other words we have an order overload. 4) As Paul Davies noted in a recent article ( www.nytimes.com/2007/11/24/opinion/24davies.html?_r=2&oref=slogin&oref=slogin ) , the multiverse does not explain the existence of laws, it merely pushes the problem up another level to the meta laws that make the multiverse operate. 5) The question ‘why is there something rather than nothing?’ has been completely ignored. |
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Post by James Hannam on Jun 2, 2008 17:03:04 GMT
Hi Humphrey,
I have never shaken off the feeling that the multiverse is just an ad hoc argument against fine tuning.
Using your numbering, I'd add:
1) A really annoying thing is the way people mix up the many-worlds quantum mechanical model with the multiverse model.
2) Unless we get some sort of process going (perhaps the evolution of universes via black holes), we haven't even got a model to play with.
3) True.
4) Arguable the existence of God poses the same problem though. You need a version of the cosmological argument for both God or the multiverse.
5) For a poor effort at this from a materialist point of view, see Peter Atkins Creation Revisited.
Best wishes
James
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Post by bjorn on Jun 3, 2008 8:57:28 GMT
One item I have heard from physists is that if an almighty God wanted to create a finetuned, life providing universe, why then didn't he do an even <i>better</i> job...
E.g. would a choice of constants (like neutrino mass weight = 0, and not a bit more than 0) that provided for even more gallaxies, stars and planets have raised the probabilty of intelligent life evolving enourmously. Which one (perhaps) could say would have served God's interest (a theological question of course) better.
In short, some rather inteligent people (like professors in physics) uses "fine-but-not-optimal-tuning" (multiverse or not) as an argument against God.
OTOH one could say that a physical optimal world (which perhaps would be hard to tell what was, as parameters and conditions (like placement of moons related to planets and planets related to gallaxy cores) have to be seen in relation to each others) constitute a formal proof for the existence of God. And would God really want us to have such a proof?
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Post by humphreyclarke on Jun 3, 2008 11:16:34 GMT
One item I have heard from physists is that if an almighty God wanted to create a finetuned, life providing universe, why then didn't he do an even <i>better</i> job... Sounds like the argument from bad design which Hitchens likes to use in his debates. The two points he always brings up is the so called big rip (not set to happen for billions of years, if at all, so its not something I lose sleep over) and the fact the Andromeda Galaxy is set to collide with us (won't happen for 2 billion years and is unlikely to have any adverse effect on us anyway because galaxies are so diffuse). To me these arguments are the same as me walking into the company I work and claiming there is no management because I have found dust in the photocopier; i.e an extreme form of nitpicking. |
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Post by James Hannam on Jun 3, 2008 11:27:46 GMT
A potential defeater for the sub-optimal fine tuning argument is that nature has been allowed a large amount of integrity. If God set the parameters at the start which would have set nature on a definite course, he has produced something less worthy of dignity than if he set rules that allowed nature to develop in a less certain way.
I suppose this is like the freewill defence writ big, but actually I do feel that evolution is just such a fre development within parameters. Simon Conway Morris has said some interesting things about what those parameters might be in his book Life's Solution on co-evolution (where you get to the same end from different start points).
Best wishes
James
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Post by humphreyclarke on Jun 3, 2008 11:38:13 GMT
Hi Humphrey, 2) Unless we get some sort of process going (perhaps the evolution of universes via black holes), we haven't even got a model to play with. Perhaps Lee Smolin’s idea doesn’t get as much stick as it deserves. I think one can get a bit caught up in the elegance of the idea and overlook its limitations. In my view it might actually be inferior to the chaotic inflation multiverse theory; although I haven’t had time to look at this in any great detail and I’d welcome feedback. To start the whole cosmological natural selection model going we need to have a self replicating universe which can produce a whole lot of daughter universes. Smolin assumes that the basic properties of these universes will be similar to ours. I can’t see a reason why this self replicator would simply pop into existence nor can I see why it should necessarily have the same types of objects and properties. There could, for example, be no such thing as a photon or an electron. There could be no such properties as mass-energy, or electric charge, or angular momentum, or space time. Overlooking all that, and assuming the process gets going, we would still have to ask the question, why this set of naturally evolving universes as there many ways in which a population of universes would not evolve. To quote George McCabe. “Not only is a population of universes which evolves by natural selection contingent, but it is also extremely non-typical. There are many ways in which a population of universes might not evolve by natural selection
1. The values of the parameters of physics might be variable in the population, but there might be no universe reproduction.
2. There might be universe reproduction, but the values of the parameters of physics might not be variable in the population.
3. The values of the parameters might be variable in the population, and there might be universe reproduction, but the number of child universes that a parent universe creates, and the lifetime of a universe, might be independent of the values of the parameters of physics. In other words, each universe type could give birth to the same number of child universes, and each universe type could have the same lifetime.
4. The values of the parameters might be variable in the population, there might be universe reproduction, and the number of child universes that a parent universe creates might be determined by the values of the parameters of physics in the parent universe, but there might be no inheritance in the reproduction
5. The values of the parameters might be variable in the population, there might be universe reproduction, the number of child universes that a parent universe creates might be determined by the values of the parameters of physics in the parent universe, and the values of the parameters of physics in a child universe could be inherited from the values of the parent, but if there is no mutation in the reproduction, then natural selection cannot take place.”
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Post by humphreyclarke on Jun 3, 2008 11:45:52 GMT
A potential defeater for the sub-optimal fine tuning argument is that nature has been allowed a large amount of integrity. If God set the parameters at the start which would have set nature on a definite course, he has produced something less worthy of dignity than if he set rules that allowed nature to develop in a less certain way. I suppose this is like the freewill defence writ big, but actually I do feel that evolution is just such a fre development within parameters. Simon Conway Morris has said some interesting things about what those parameters might be in his book Life's Solution on co-evolution (where you get to the same end from different start points). Best wishes James SCM has a new book out called 'The Deep Structure of Biology' which is a collection of essays by various scientists on evolutionary convergence. It includes one by a distant cousin of mine, Hal Whitehead, who has noticed many convergences between sperm whales and land mammals such as elephants, but perhaps more than that. Hal claims that the most important thing is that Whales have 'culture' or to put it more dryly 'the complex and stable vocal and behavioural cultures of whales appear to have no parallel outside humans, and represent an independent evolution of cultural faculties'. Amongst observed behaviours are distinct languages with different dialects, the formation of complex social groups, babysitting, social learning and of course, song learning and sharing. Makes me think twice about serving them up with a plate of chips. There seems to be many examples of evolution through different habitats and pathways but with similar results. One can also see this in the fact that Corvids (in particular the New Caledonian Crow) exhibit tool making skills superior to the primates despite having different brain architecture. The most fascinating discoveries to me have been the observation of intelligent behaviour in plants. |
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Petersean
Clerk
A page of history is worth a volume of logic.
Posts: 36
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Post by Petersean on Jun 3, 2008 21:51:33 GMT
A potential defeater for the sub-optimal fine tuning argument is that nature has been allowed a large amount of integrity. If God set the parameters at the start which would have set nature on a definite course, he has produced something less worthy of dignity than if he set rules that allowed nature to develop in a less certain way. Interesting. This is the way that Aquinas phrased your idea: The idea of the granting creation the "dignity of causality" caught my eye when I first read this passage. Presumably, the "dignity of causation" would extend to the development of species from earlier species. |
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Post by unkleE on Jun 8, 2008 10:12:01 GMT
I thought I'd give my take on the original question - please note I am very much a layperson, though I have read a bit on fine-tuning and the multiverse. 1. I see no reason, as a theist, to disbelieve the multiverse on theistic grounds. To do so may be another God of the gaps pitfall. Perhaps one day the multiverse will be proven, though I doubt it, and I don't want to pin my belief on that gap. As others have said, whether there's one fine-tuned universe or many chaotic ones, a theist (and even a former atheist like Flew) may feel a god is a better explanation than chance or the unknown. 2. But I feel the multiverse is rather unbelievable on logical grounds. For it to work as an answer to the design argument, there have to be sufficient universes in the multiverse to make life reasonably possible. Now there have been various estimates of the probability of a universe suitable to produce complex life forming by chance - I can remember at least these three: - Roger Penrose (both a mathematician and a cosmologist), in "The Emperor's New Mind" calculates the probability as 1 in 10^10^123, an unimaginatively large number and small probability. To put it in perspective, there are about 10^80 baryons in the universe. To write this number requires 80 zeroes. To write Penrose's number requires more zeroes than there are baryons.
- Lee Smolin estimates the probability that the universe will contain stars is 10^229, a much smaller number and larger probability than Penrose's, but still a very small likelihood, and he's not estimating the same thing.
- Victor Stenger has a very simplifed model that shows that the universe would last long enough for stars to form in about 50% of his random trials. Even granted his model is simplistic, his estimate doesn't gel with the other two and one suspects his metaphysics got in the way of his science.
If we believe Penrose (he has the best credentials I would have thought), there would have to be some number approaching 10^10^123 universes to make our one reasonably probable, so we're not just talking about a few. In fact it leads to the conclusion, which some theorists like Suskind and Rees speculate on, that there are an infinite "number" of universes. But this raises other problems. I think the jury is out on whether an infinite set of physical objects is possible, but I also think everyone agrees that you can't get there sequentially. Thus we can't have an infinite number of universes stretching back to time minus infinity, and we have to have all the infinite universes being "created" all at once - at least that's my reading of some of the philosophy/mathematics. So we come back to something beyond science and beyond my belief - an infinite number of universes appearing "all at once", for no apparent reason, unless God did it. So I conclude that the multiverse is only probable or perhaps even possible if God did it. But then, I already have a belief in a god. Perhaps some of you more learned members can show me where my thinking has gone wrong. |
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Post by humphreyclarke on Jun 9, 2008 11:39:33 GMT
Now there have been various estimates of the probability of a universe suitable to produce complex life forming by chance - I can remember at least these three: - Roger Penrose (both a mathematician and a cosmologist), in "The Emperor's New Mind" calculates the probability as 1 in 10^10^123, an unimaginatively large number and small probability. To put it in perspective, there are about 10^80 baryons in the universe. To write this number requires 80 zeroes. To write Penrose's number requires more zeroes than there are baryons.
- Lee Smolin estimates the probability that the universe will contain stars is 10^229, a much smaller number and larger probability than Penrose's, but still a very small likelihood, and he's not estimating the same thing.
- Victor Stenger has a very simplifed model that shows that the universe would last long enough for stars to form in about 50% of his random trials. Even granted his model is simplistic, his estimate doesn't gel with the other two and one suspects his metaphysics got in the way of his science.
If we believe Penrose (he has the best credentials I would have thought), there would have to be some number approaching 10^10^123 universes to make our one reasonably probable, so we're not just talking about a few. In fact it leads to the conclusion, which some theorists like Suskind and Rees speculate on, that there are an infinite "number" of universes. I really cannot fathom how Stenger has managed to come up with a multiverse model which produces life in 50% of universes (Any idea James?). The only reason I can think of is that he is appealing to ignorance, i.e we are all Carbon Chauvinists and that somehow life can emerge from some other substance as long as there is some sort of star formation. However, since Susskind is saying that the probability of universe with stars is 10^229, I don't even see how he came up with that. The problem with Stenger is that only the most militant of atheists seem to take him seriously and as a result no-one seems to have undertaken a decent refutation. Given that most of these multiverse models seem to be infinite, the consensus of Cosmologists must be that fine tuning is very improbable indeed. Another point worth making is that if there were an infinite multiverse that happened to spring into existence and it had the potentiality to create us then it is equally probable that it would have a god in it since everything that can exist will come into existence. This is where Paul Davies description of the multiverse in 'The Goldilocks Enigma' breaks down into absurdity because it will be likely that this multiverse will produce civilisations caperble of reaching Tipler's Omega Point and therefore become god like entities running computer simulations of universes. At this point things become very silly indeed and one is tempted to reach for Occum's machete. As Paul Davies notes: Mathematicians have proved that a universal computing machine can create an artificial world that is itself capable of simulating its own world, and so on ad infinitum. In other words, simulations nest inside simulations inside simulations ... Because fake worlds can outnumber real ones without restriction, the "real" multiverse would inevitably spawn a vastly greater number of virtual multiverses. Indeed, there would be a limitless tower of virtual multiverses, leaving the "real" one swamped in a sea of fakes.
So the bottom line is this. Once we go far enough down the multiverse route, all bets are off. Reality goes into the melting pot, and there is no reason to believe we are living in anything but a Matrix-style simulation. Science is then reduced to a charade, because the simulators of our world - whoever or whatever they are - can create any pseudo-laws they please, and keep changing them. So the thought occurs, in order for an atheist multiverse to create a universe caperble of producing us and yet not create a universe caperble of creating a god like entity, it would have to be fine tuned; vast enough to solve the fine tuning problem but not so vast that almost anything can exist. So the atheist needs fine tuning to solve the fine tuning. |
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Post by unkleE on Jun 13, 2008 1:11:30 GMT
Very interesting post!
To be fair to Stenger (not that I think he's fair in return!), his simulation only predicts how long the universe will last, using only a few parameters. Where he is unfair is to then say because that simplistic model predicts 50% probability of lasting a billion years or so, then the real universe is not so improbable.
I have long been a fan of Paul Davies (I know James isn't) - his "The Mind of God" was very open-minded, and helped convince me and others that the fine -tuning argument pointing to God had legs. I haven't read his latest book, although I have read about it (including his own summary) and I thought it was a poor back-track for him. But your quote made me wonder how much he's actually demolishing the multiverse and other "evasions" of the fine-tuning problem by reductio ad absurdum.
I find it interesting that open-minded but non-theistic scientists like Rees and Susskind can dismiss the God hypothesis as "unscientific" and yet accept the multiverse, which seems to have even less evidence. But in the end, I believe God has quite deliberately left us with enough evidence for those with eyes to see to choose to believe, but not so much as to compel belief.
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Post by humphreyclarke on Jun 13, 2008 9:51:52 GMT
Very interesting post! To be fair to Stenger (not that I think he's fair in return!), his simulation only predicts how long the universe will last, using only a few parameters. Where he is unfair is to then say because that simplistic model predicts 50% probability of lasting a billion years or so, then the real universe is not so improbable. I have long been a fan of Paul Davies (I know James isn't) - his "The Mind of God" was very open-minded, and helped convince me and others that the fine -tuning argument pointing to God had legs. I haven't read his latest book, although I have read about it (including his own summary) and I thought it was a poor back-track for him. But your quote made me wonder how much he's actually demolishing the multiverse and other "evasions" of the fine-tuning problem by reductio ad absurdum. I find it interesting that open-minded but non-theistic scientists like Rees and Susskind can dismiss the God hypothesis as "unscientific" and yet accept the multiverse, which seems to have even less evidence. But in the end, I believe God has quite deliberately left us with enough evidence for those with eyes to see to choose to believe, but not so much as to compel belief. I got the impression from 'The Goldilocks Enigma' that Paul Davies is a closet deist. He does give a fair and balanced discussion of all the various options with the exception of Smolin's cosmic evolution and the alternative biochemistry arguments that Stenger brings up. It looks like he is favouring the multiverse until the end of the chapter when the whole thing breaks down into overwhelming silliness. He also points out that if there was a theory of everything it would be the greatest fine tuning fix of them all. He also discusses the possibility of intelligent design and whilst he is superficially sceptical you get the sense that he doesn't hold it in the same contempt his scientific colleagues do. His preferred option is a bizarre theory which is a mismash of quantum teleology and observer selection which makes no sense whatsoever. Since intelligent design was the most kindly treated and the implications of the multiverse theory is to place 'reality in the melting pot' I think the reader, while not being steered towards invoking god, certainly can see that it is the least worst option. It sounds as if PD has backtracked by your description of his earlier book but since it is career suicide to invoke god this is understandable. I admire him for bringing an open mindedness to an area of cosmology which is characterised by wild speculation, close mindedness and controversy. |
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Post by revrevelation on Jun 15, 2008 15:10:12 GMT
delete double post...but I will think of something to stick in here after Sunday school ....
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Post by revrevelation on Jun 15, 2008 15:12:21 GMT
I am a proponent for William Craig's (PhD ThD) KCA and Kurt Godels OA. I do not get too excited about the MWT of string theory and feel for now it being a untestable and non predictive theory does not meet the criteria of theory. In any case if there are many universes or worlds mine has God in it! ; }>
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Post by humphreyclarke on Jul 25, 2008 16:09:39 GMT
Random bit of trivia. Apparently David Icke uses the multiverse to argue for the plausibility of his theory that the world is controlled by a bunch of shape shifting lizards who conduct blood rituals and human sacrifices. After all, as he says, given an infinity of worlds, it would be 'staggering' if sentience had not evolved down the reptilian line.
http://ww w.youtube.com/watch?v=Hj8GWcwfQrU&feature=related
Good to see that the metaphysical ruminations of Susskind, Tegmark and Rees etc.. can be used to argue for practically any loony theory you care to mention.
So much for scientific elegance.
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