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Post by humphreyclarke on May 7, 2009 8:45:19 GMT
b) The many forces of the universe can be changed and you can still get stars that will live long enough for life to evolve. Isn't this a fly in the ointment? I have to say I am deeply, deeply sceptical about this one. Lee Smolin, one of the world's leading theoretical physicists says in 'The Life of the Cosmos': tinyurl.com/d5qlm8 What is the probability that the world so created [with random values of the parameters] would contain stars?. The answer is that the probability is incredibly small. This is such an important conclusion that I will take a few pages to explain why it is true. In fact the existence of stars rests on several delicate balances between the different forces in nature. These require that the parameters that govern how strongly these forces act be tuned just so. In many cases a small turn of the dial in one direction or another results in a world, not only without stars, but with much less structure than our universe.He then discusses for several pages the parameters that need to be ‘just right’ Brief Summery – Conditions for suitable star Formation1) Protons, neutrons, electrons and neutrinos interact via four basic forces. Gravity, electromagnetism and the strong and weak nuclear forces. 2) Newton’s gravitational constant is incredibly weak. This is vital for stars because the weaker gravity is , the more protons must be piled on top of each other before the pressure is strong enough to produce nuclear reactions. Stars are therefore so huge because the constant is so tiny. If they were not huge then they wouldn’t be able to burn for billions of years (they usually burn for 10 billion years). If it were stronger by only a factor of 10, stars would only burn for 10 million years (good luck getting life out of that). If it were stronger by another 10 then the lifetime of a star would be 10,000 years. 3) Stars burn through nuclear reactions that fuse protons and neutrons into a succession of more massive nuclei. For this to happen the masses of the elementary particles must be chosen very delicately. The strengths of the forces must also be carefully tuned. If they were even slightly different then there would be no way to get stable nuclei. Stars cannot burn if there are not stable nuclei 4) Why is the universe big enough for stars?. Why does it live for the billions of years needed for stars to form?. This depends on the Cosmological constant which can be no larger than about 10 to the power minus 40. If it were not, stars would not live long enough. 5) If it were not for the strong nuclear force, nuclei would be blown apart. Remarkably the attractive nuclear force actually balances the electrical repulsion of the protons. If there were not this fine balance there would be no stability and no nuclei. Our existence depends on it 6) The weak nuclear interaction much be set up in order to govern the basic nuclear reactions on which the physics of stars is based. ......Perhaps before going any further we should ask how probable it is that a universe created by randomly choosing the parameters would contain stars. Given what we have already said, it is simple to estimate the probability. For the readers who are interested, the arithmetic is in the notes. The answer in round numbers, comes to about one chance in 10 to the power 229.
To illustrate how ridiculous this number is, we might note that the part of the universe we can see form earth contains about 10 to the power 22 stars which together contain about 10 to the power 80 protons and neutrons, These numbers are gigantic but they are infinitesimal compared to 10 to the power 229. In my opinion a probability this tiny is not something we can let go unexplained. Luck will certainly not do here: we need some rational explanation of how something this unlikely turned out to be the case.
So something has gone badly wrong with the study you are referring to. Perhaps their metaphysics got in the way of their brain functioning?. Perhaps they think any star will do for the creation of life, even if it only lasts for a couple of years. All this despite the fact that it takes billions of years of star formation just to get the heavy elements necessary for life.
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Post by Al Moritz on May 7, 2009 8:51:24 GMT
a) What's to say that life could have evolved under different circumstances? Non organic life or life that could live in ridiculously hostile environments (like the "living" space dust found a few years ago)? Or life that could adapt to a completely different set of physical laws => completely different chemical laws? I think there are two answers to this. One is that given to your second question (below). The other is that biochemists can present arguments to show that, with our current understanding of chemistry, there are severe limitations on what could be used as the building blocks of life. Because it may be possible to conceive of a completely different basis for chemistry (i.e. not the current fundamental particles, or atoms, or the current periodic table, but something completely different), I don't think much of the second answer, but the one below is quite telling I think. Here are some thoughts that I had written a while ago, and which I will re-post here: Yet wait a minute, the atheist will say: perhaps “life as we know it” may be extremely unlikely, but couldn’t it be that many different forms of life were possible and thus that life in any form is not unlikely at all? One who studies this issue sufficiently will know that not just life as we know it, but any chemical complexity requires highly specialized laws of nature. Any detuning, and any chemical complexity would be impossible. Just hydrogen, and possibly deuterium and helium (or equivalents), and no chemistry. We know that material life requires complexity of matter, and complexity of matter is impossible without chemistry. Therefore, if several of the physical constants were freely variable, then the chances to arrive at any laws of nature that allow for material complexity – thus any kind of life, not just life as we know it – would be very low. Our universe with its specific laws of nature would be a small oasis within a vast desert of a humongous number of sterile, non-complex universes where no chemistry takes place. If, on the other hand, there would be a completely different kind of life in a completely different kind of universe with laws of nature that do not at all resemble what we have (and which also produce entirely different particles), it is still the most rational assumption that this life would be based as well on some material complexity, which in turn would be based on some sort of alien chemistry (being a semi-closed system and metabolism require complexity, there is no disputing that). And furthermore, we would rationally expect by extrapolation from our laws of nature (we have nothing else to go by) that also here any slight detuning of physical constants would make that alien chemistry impossible. Thus, another small oasis within a vast desert of a humongous number of sterile, non-complex universes where no chemistry takes place. Overall, then, even if some entirely different form of life might be possible somewhere else under completely different conditions, the probability for any life, known or unknown, most likely still remains very low. The argument might be brought up, “life could theoretically occur in ways we would never imagine, or would not even think of as life at all”. Yet the idea of life without any chemical complexity (e.g. in stars), leads one into regions of thought that are not seriously debatable anymore and which have no basis in our knowledge from science. Also, I have never seen it discussed in those terms by a scientist. Imaginative thinking is one thing, wild baseless science-fiction another. Yes, this is important. Yes, Stenger's opinions are fringe opinions outside mainstream science, and major cosmologists, including atheistic or agnostic ones, all take the apparent fine-tuning very seriously. Hawking, Rees, Davies, Suesskind, Linde, Weinberg, Ellis come to mind off the top of my head. Stenger is popular among atheists because his opinions so easily play into their world view. Interesting how "science-minded" people are willing to ignore mainstream science once other views seem more "suitable".
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Post by Al Moritz on May 7, 2009 8:55:59 GMT
I did not see Humphrey's post before I sent mine. It addresses the point quite clearly. By the way, to my knowledge Smolin is an atheist, or at the least agnostic.
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Post by humphreyclarke on May 7, 2009 8:56:12 GMT
a) What's to say that life could have evolved under different circumstances? Non organic life or life that could live in ridiculously hostile environments (like the "living" space dust found a few years ago)? Or life that could adapt to a completely different set of physical laws => completely different chemical laws? This is true but the universe would still have to have roughly the same properties as this one. So for example, in this universe we have an over-abundance of order, conceivably you could have a bit less order and still get life but the forces would still have to be balanced for a stable enough environment in which life could develop. You would still need the right sort of star formation to get heavy elements. Life would have to be based on something like carbon. Attempts to get a workable life chemistry about of silicon have never advanced beyond science fiction. We would almost certainly have to have water. If we want complex life like that which exists on this planet we would need a whole load more 'fixes' Of course you could argue that I cant know for sure that we need those things and that's true, in the same way that I can't say for sure that an exact copy of the Encyclopaedia Britannica wasn't created by chance sometime after the big bang, but I can make an educated guess based on the best science.
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Post by humphreyclarke on May 7, 2009 9:03:17 GMT
My goodness Humphrey, where do you get the time (not to mention the brian power!) to keep up with so many subjects - history, cosmology, neuroscience, evolution? You truly are a renaissance man and have my admiration and thanks. Thanks Unklee! Although you could say 'Jack of all trades, master of none' and I do keep daydreaming and forgetting where I put my keys. It helps being involved in a colossal argument which touches on pretty much every subject there is.
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Post by unkleE on May 7, 2009 9:13:20 GMT
It helps being involved in a colossal argument which touches on pretty much every subject there is. Is this a public argument where we can all visit and cheer you along, or do you prefer to remain modestly reticent? I'd be interested.
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Post by humphreyclarke on May 7, 2009 9:20:35 GMT
It helps being involved in a colossal argument which touches on pretty much every subject there is. Is this a public argument where we can all visit and cheer you along, or do you prefer to remain modestly reticent? I'd be interested. ;D Well, I haven't actually been involved in an online argument for a long time. Probably a good thing. I was referring to the wider 'struggle' with the Dawkinsia. The last one was some guy telling me if I wanted to claim Copernicus as a devout Catholic I had also to accept Adolf Hitler as a devout Catholic. Dunno how much 'mental pot' you have to smoke to come up with that one.
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Post by knowingthomas on May 7, 2009 21:09:25 GMT
But with the fine tuning, isn't it the reason that they seem so fine tuned is due to our man made measurement system?
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Post by unkleE on May 7, 2009 22:28:27 GMT
But with the fine tuning, isn't it the reason that they seem so fine tuned is due to our man made measurement system? I'm sorry, but I'm not sure I understand what you mean. Perhaps the clearest statement of fine-tuning probabilities comes from Penrose in Emperor's New Mind, where he calculates the size of the "phase space" of all possible values of the parameters he is considering, and the small portion of this phase space which would "provide a universe compatible with the second law of thermodynamics and with what we now observe". Thus his calculation is not based on measurement system, but on simple numbers, and the ratio between them, which gives a probability (Probability = Number of "successful" outcomes/Total number of possible outcomes) which he calculates as 10^10^123.
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Post by knowingthomas on May 7, 2009 23:28:26 GMT
But with the fine tuning, isn't it the reason that they seem so fine tuned is due to our man made measurement system? I'm sorry, but I'm not sure I understand what you mean. Perhaps the clearest statement of fine-tuning probabilities comes from Penrose in Emperor's New Mind, where he calculates the size of the "phase space" of all possible values of the parameters he is considering, and the small portion of this phase space which would "provide a universe compatible with the second law of thermodynamics and with what we now observe". Thus his calculation is not based on measurement system, but on simple numbers, and the ratio between them, which gives a probability (Probability = Number of "successful" outcomes/Total number of possible outcomes) which he calculates as 10^10^123. What I'm saying is that aren't the measurements arbitrary because they are based on our particular units of measurement? A typical example of this argument is John Jefferson Davis: "If the mass of neutrinos were 5 x 10^-34 instead of 5 x 10^-35 Kg, because of their great abundance in the universe, the additional gravitational mass would result in a contracting rather than expanding universe." Sounds like a small amount, right? Wrong - it is making the neutrino 10 times heavier than it is. That is similar to arguing that if Michael Jordan were just 10^-16 light years shorter he wouldn't be a good basketball player. Physical constants are made up numbers based on our units of measure.
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Post by unkleE on May 8, 2009 0:02:41 GMT
But these things are almost always about ratios of physical constants, which are dimensionless, and hence not dependent on units of measurement.
And the change suggested in the mass of neutrinos is large arithmetically, but not large geometrically, or in order of magnitude, which is how most of these things are considered (e.g. if you read Penrose, he substitutes 10 for e because when you are talking about 10^10^123, the ratio of 10/e = 3.7 is irrelevant!). But in the end, it is the experts (Penrose, Rees, Smolin, Davies, Susskind, Weinberg) who say the fine-tuning is beyond coincidence, and unless we know a lot, who can argue with them?
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Post by humphreyclarke on May 8, 2009 6:38:25 GMT
This is a kind of postmodern, and I might say, a rather anti-scientific argument. Yes mathematics is something that has been discovered and developed by human beings and uses human concepts; but everything we use to analyse the world is a man made discipline. Mathematics is a highly effective one and physics is an enterprise built on the idea that it accurately describes the properties of the universe. So when people like Smolin and Sir Martin Rees say that only a small change would kill the chances for life, I believe them. Its also not obvious to me that the changes are exaggerated. Lets take Unklee's number for example 10^10^123 (this is the probability of the universe we observe under Roger Penrose's WEYL Curvature hypothesis). The accuracy involved is roughly the same as firing an arrow from one end of the universe to the other and still being able to hit a normal sized target. Now I would say that is impressive (a human concept), but maybe the guy you are arguing with wouldn't. If I were you I would suggest that your friend takes his astonishing insight to Penrose, Rees, Smolin, Davies and Susskind. After all, as Unklee points out, they all think fine tuning is a real problem and beyond coincidence. If your friend is right then they have just been deluding themselves with made up units of measurement. He might want to mention they have been wasting their lives trying to describe the physical universe and should give up doing science. Also: www.theologyweb.com/campus/showthread.php?t=127076&page=6The multiverse is not just assumed. Even if other universes have not been directly observed, they are the direct consequence of quantum physics which has overwhelming experimental support. We may not have observed directly those other universes, but they are a logical consequence of the observations of the quantum world that we can indeed make. Now I would agree that this is not proof that such other universes exist. Science cannot answer that question definitively at this point, and most likely won’t be able to in our lifetime. But it is incorrect to argue that the multiverse is just an assumption – it is the logical consequence of quantum physics. So the multiverse is now the 'logical consequence' of quantum mechanics?!?!. What the hell is he talking about. First our universe is not very well fine tuned for life. The vast expanses of our universe are completely inhospitable to life at all. A rather simple calculation would show that even if every star had a planet on which life existed, the volume of space in which life was habitable would be a mere 10^-21 of the entire volume. (taking our biosphere to be approximately 20 miles wide surrounding the earth, and the nearest star being 4.36 light years away) So in the entire scheme of things, the universe doesn’t look very well designed just for life. It seems mostly designed for empty space.See bedejournal.blogspot.com/2009/01/why-is-universe-so-big.html , or for a better discussion (and a very good book in general) i would recommend Barr's 'Modern Physics, Ancient Faith'.
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Post by knowingthomas on May 12, 2009 19:30:21 GMT
The cosmological argument is still pretty good. You can get it from the experts, like philosophers William Lane Craig or Bill Ramey, or you can just go by common sense and decide whether you think the universe has no cause, or is infinite, or has a cause, and if it has a cause, what else other than God. I find it convincing. The problem I see with this is the canard "God of the Gaps", which applies to the fine tuning principle too. Yes, no theory yet can solve this problem of a universe coming out of nothing, but what's to say one can be found in the future? On the topic of not using science to prove God: www.youtube.com/watch?v=6eCwTkJQ2DQwww.youtube.com/watch?v=mG6dzbg2lGE&feature=response_watchwww.youtube.com/watch?v=9dLZKEQuijI&feature=response_watchBut isn't this more of a refutation of naturalism, not a proof of God? My distrust of the moral argument was from the recent debate Craig had with Kagan. It just seems to me that it's not really persuasive. :/ The biggest issue about Jesus is the problem that he accepts the validity of the OT as historical. There's numerous problems with this given the state of Old Testament study. Matthew 17:3 and Mark 9:4 has Jesus talking with Moses and Elijah. Most OT historians don't even believe that Exodus even happened, let alone that Moses and Elijah existed at all. The Patriarchs are even worse for wear. The book of Samuel being a composite of Pro-Monarchy and Anti-Monarchy sources. The many theories of the origin of Yahweh worship in the Canaanite religion or from Mesopotamian composite gods. If Jesus was God, why would he believe the OT was true?
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Post by Al Moritz on May 12, 2009 19:55:49 GMT
The problem I see with this is the canard "God of the Gaps", which applies to the fine tuning principle too. Yes, no theory yet can solve this problem of a universe coming out of nothing, but what's to say one can be found in the future? As I see it, the "God of the Gaps" applies to workings within nature, or unexplained phenomena within nature -- see the Intelligent Design and similar movements. The cosmological and the fine-tuning argument, however, deal with the origin of nature itself -- our universe. And, if you think that the problem of a universe coming out of nothing is a scientific problem, you are mistaken. True nothing is absolutely nothing, and absolutely nothing (the philosophical nothing that is) has no properties whatsoever, and thus no potentiality towards anything, and therefore cannot generate anything. When cosmologists talk about nothing, they usually mean the physical 'nothing' of the quantum vacuum, which really is not nothing at all: en.wikipedia.org/wiki/Vacuum_stateAnd when they confuse the physical 'nothing' with the philosophical nothing, like for example Victor Stenger does, they simply engage in bad philosophy and make as travesty out of science. A universe coming out of nothing is a philosophical problem, not a scientific one. Science cannot investigate something that has no properties whatsoever.
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Post by James Hannam on May 12, 2009 20:00:57 GMT
If Jesus was God, why would he believe the OT was true? This is not the serious answer that you are asking for, but your question reminded me of the scene in the Life of Brian where he gets pelted with stones. Mark 24:18 - "And Jesus said unto them, "The Torah is not true." And they were most displeased." They would hardly have needed the Romans to do away with him if he'd said that. Best wishes James
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