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Post by humphreyclarke on Apr 28, 2009 20:56:00 GMT
The video are up for the Origins Symposium featuring some of the world great intellects...oh and A.C Grayling appears to have tagged along as well. thesciencenetwork.org/programs/origins-symposium/science-society-and-the-merchants-of-lightHere is a great bit of 'conflict thesis' rabble rousing from the man himself thesciencenetwork.org/media/videos/363.pdf'It is quite a good point, because we have just come out of a period of turmoil, there is conflict in the world of a serious kind which the U.S. is deeply engaged in, and we have got this economic difficulty that we find now, just come out of a double presidency, a two terms president who has been very inimical to science, and Lawrence is right about that, and there are some parallels with 1660, the civil war period, the commonwealth period, the restoration of the monarchy and so on, so there are these superficial analogies at the very least. But one thing one has to remember is that the foundation of the Royal Society was not just the origin of something, or the beginning of something very important in the institutionalization of science as an important thing in society, but it was the end product of something, of 100 years of struggle between, on the one hand, the emerging empirical studies, and on the other, reactionary forces, in particular the church, that was made very anxious by some of the things that the new sciences were saying, and the fact that an institution could be set up in 1660 was the mark of a success, that there had been a victory of an intellectual kind at the end of that century, that had started with Copernicus and all the great changes there. So it is an important point to remember that, that it is a mark of a stage in a process which has been a longer and a richer one.
Looks like there is some interesting discussion about the multiverse.
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Post by humphreyclarke on Apr 29, 2009 7:58:09 GMT
Bit of discussion on the multiverse here : thesciencenetwork.org/programs/origins-symposium/panel-2-is-our-universe-unique-and-how-can-we-find-outAlan Guth Guth says that Inflation and String theory points to a much larger universe. The challenge is to calculate the possibilities that might exist in this universe with infinite regions. It looks like there have been some problems as a lot of these lead to absurdities. Some predict much smaller universes, some predict that Botzmann brains which will be the observers that dominate the universes. Very hard to calculate probabilities, don’t understand the product of intelligent life enough. My view on Guth's talk that it seems to be a bit glib to rule out a multiverse model because it leads to absurdities. If you end up with a universe in which everything possible exists (all these models seem to be infinite) you will inevitably get an abundance of absurdity. I see no reason why if, we dont live in a multiverse, that there shouldn't be a multitude of disembodied brains floating around; in fact it should be expected. (see en.wikipedia.org/wiki/Boltzmann_brain) VilenkinVilenkin brought up the Cosmological constant problem and said that it indicates that there are a vast number of universes. ('I can't explain X, therefore there are infinte universes') David Gross - (Reality Check)Gross began with an introduction. The multiverse is based on idea of a multitude of possibilities, the idea that there exist a large number of universes in which the parameters vary. The ones that make up our universe are very rare. String Theory indicates there are 10 to the 500 ‘vacua’ with carrying parameters and features. There will also need to be a dynamical mechanism for populating these universes. Some say this is provided by inflation. Point One – the ‘vacua’ of string theory are all meta-stable, most are uncontrollable and none constitute a consistent cosmology. They are nothing more than approximate solutions. Point Two - The mechanism of eternal inflation and the multiverse is technically and conceptually shaky. Postulating a series of causally disconnected regions of some kind of configuration space is something that would have challenged medieval theology. Point Three – We still do not know what String Theory is. Does it even deserve the name theory?. Should be called a’ framework’. Many suspect there is something important missing. Gross is very suspicious of Anthropic arguments which invoke multiverses 1) They are hard (actually impossible) to falsify, and often tautological. 2)They go against history. Its a remarkable fact that the entire normal observable world is in principle explainable in terms of the standard model of physics with very few parameters without resorting to the Anthropic Principle. Indeed the understanding of atomic physics and thus the properties of ordinary matter, atomic physics, chemistry and life require only the principles of Quantum mechanics, the existence of nuclei, the theory of electro magnetism and one undetermined number that measures the strength of the electric force. It seems just wrong, after a millennium of success to retreat to anthropic arguments to explain the few things we can’t explain. Its an easy way out and it thrives on ignorance. The more you don’t know the more your theory explains. So 1) We are not sure what the final theory is and what the rules of the game are 2) We suspect that space and time are emergent concepts. In view of this our understanding of the foundations are shaky and we cannot claim to know the selection mechanism for the universe. 3) Just because we can’t produce a solution for why the cosmological constant problem, doesn’t mean a solution doesn’t exist. For example Dirac solved the big number problem without invoking anthropic arguments. Strategy should be to observe, experiment and calculate. Go back to doing science. Sheldon GlashowGlashow looks forward to a day when we will actually have some observations and experiments in contrast to things like string theory that are not falsifiable.
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Post by knowingthomas on May 1, 2009 5:48:15 GMT
Well that's discomforting. I'm not really sure I understand the ins and outs of the issue. Did Dirac "wound" the anthropic argument? Or am I completely misunderstanding this statement?
Which one is it/more likely? A single fine tuned universe or the multiverse/many worlds/Hawking's Kitchen Sink? If the multiverse/many worlds was proven, would the design argument be refuted?
It's kinda troubling. I mean, Jesus for me is a really good argument, but besides the fine tuning principle and the moral argument (which is incredibly shakey), I really have nothing to go on.
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Post by humphreyclarke on May 1, 2009 8:36:19 GMT
Well that's discomforting. I'm not really sure I understand the ins and outs of the issue. Did Dirac "wound" the anthropic argument? Or am I completely misunderstanding this statement? Which one is it/more likely? A single fine tuned universe or the multiverse/many worlds/Hawking's Kitchen Sink? If the multiverse/many worlds was proven, would the design argument be refuted? It's kinda troubling. I mean, Jesus for me is a really good argument, but besides the fine tuning principle and the moral argument (which is incredibly shakey), I really have nothing to go on. Seriously, you don't have anything to worry about David Gross is a practising Jew and deeply sceptical of multiverse explanations (that is what he means by 'anthropic arguments that invoke multiverses'). What he particularly goes against is the idea that you can explain something in science by saying, 'well that must mean there are multiple universes!'. Dirac was able to solve the large number problem simply by establishing a relationship between the numbers in question. In other words he looked for beauty, order and simplicity; not chaos and insanity which is what the inflationary multiverse ultimately is. As for the multiverse, well it might be true. Actually I cant think of a good reason why there shouldn't be a multiverse. One thing is for sure, we will probably never know whether there is or isn't one this side of the grave. If it existed, would it solve the fine tuning problem?. Yes but at the expense of creating a whole host of new problems. A multiverse is defined as an ensemble of universes within which the members may differ from one another. They might be completely disconnected space times, or spaces joined occasionally, or widely separated contiguous space times. Our particular laws of physics would only apply in our patch. This would answer the question of why the laws of physics have the requisite mathematical form and assume the relevant values of various parameters within those laws so that the universe will bring forth life and conciousness. Does this provide an ultimate explanation?. No. Each set of universe will have to come equipped with a set of mathematical laws that are similar to our universe. The foundational properties of the universe are going to have to be pretty similar to ours in order for this multiverse to give birth to anything. We will also need a special set of laws to guide the functioning of the multiverse. How is one to ensure that the “bubble” universes brought about by the unending series of inflation events exhibit lawlike behavior of any sort, let alone the probabilistic distribution of such behaviours that the fine-tuning argument requires. There is also a bias in the assumption that the laws should be mathematical (why not teleological laws, why not using very different mathematics -e.g fractals?). An infinite number of universes with the same basic blueprint as our would inevitably produce a host of traditional deities and some alien ones. It would also produce disembodied Boltzmann brains and, as Paul Davies has suggested, simulated universes would start to outnumber the non-simulated ones. A multiverse rich enough to produce sentient beings is also one in which simulated beings are likely to outnumber unsimulated ones. So one can invoke multiverses but to make them able to explain our particular universe, they grow increasingly more silly and make the whole nature of reality a sick joke. Furthermore the system would need some sort of fine-tuning so it solves absolutely nothing. it just pushes the design argument up another level.
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Post by Al Moritz on May 1, 2009 9:00:31 GMT
The multiverse solves the fine-tuning problem of our particular universe, but does not solve the design problem and creates another fine-tuning problem: a truly random distribution of physical constants among the members of the multiverse (in order to solve the 'fine-tuning' problem) could only be achieved by careful design of the underlying multiverse generator. Conversely, if the distribution of physical constants were not truly random, the question would again arise as to who or what made the choices. Instead of solving the designer problem, the multiverse theory just pushes it back one step, and thus accomplishes nothing. As Stephen Barr explains in his book Modern Physics and Ancient Faith, “having laws that lead to the existence of domains of a sufficiently rich variety to make life inevitable would itself qualify as an anthropic coincidence.” (p. 154). See also: home.messiah.edu/~rcollins/finetune/anth.htm.htmHeading, "Theistic Responses to Many-Universe Generator Scenario"
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Post by unkleE on May 1, 2009 12:15:46 GMT
It's kinda troubling. I mean, Jesus for me is a really good argument, but besides the fine tuning principle and the moral argument (which is incredibly shakey), I really have nothing to go on. There's plenty more than that (I think). 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. Alvin Plantinga also has an interesting (and to my mind convincing) argument based on reason. It was earlier argued by CS Lewis in Miracles, and developed into a PhD thesis and subsequent book by Victor Reppert. I think the moral argument is more convincing than you apparently do, especially when combined with considerations of freewill. Whatever other people may think, I think it is clear that we can't really live as human beings without believing we have freewill and that ethics are really true. Many people say they can, but I think their language and responses to issues shows otherwise. And, as in the argument from reason, evolutionary naturalism can't explain this. So, in my opinion, we are left with the choice of believing in God or disbelieving and living contrary to our logic. So I find that argument convincing also. I find it hard to believe that every last one of the many claimed experiences of God, including communications, grace and healings are all fakes or mistakes. I have read of, heard of from reliable friends, or experienced a very small number of these which seem genuine, so there must be more out there, and every one is a pointer to God. Finally, I think Jesus on his own is quite sufficient reason to believe, although it is nice to have these additional confirmations. If you want to read about someone else's summary (in this case William Lane Craig), try here.
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Post by knowingthomas on May 2, 2009 7:10:04 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. But I thought that to say everything came into existence at t=0 is not scientifically supported; that the universe is eternal and matter is finite... . What is scientifically supported is space time matter as we know it came into being from the big bang, right? Isn't energy eternal and it is probable that some eternal substance exists and is behind the cause of the universe from the big bang? This doesn't mean matter poofed from nothing, right? It reminds me of an online discussion I've read recently (Bold vs Italics): "The universe cannot be eternal, philosophically and scientifically." Yes it can. You think God can be eternal so why can't I say the sum of existence is eternal? Matter isn't eternal, but it's a false dichotomy to say either God exists eternally or matter exists eternally.actual infinites don't exist in the physical universe; God is actually infinite but transcends the physical universe and is not bound there-in or there-by. You have no basis to say what the universe may include. Your equivicating my definition of the universe which is all that exists with your limited idea of what you call the universe, space, matter and time. Also you haven't proven that finitude of time correlates with ontological beginning of the physical universe. Two problems that apologists readily ignore in favor of attacking a straw man atheism.
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Post by humphreyclarke on May 2, 2009 11:22:09 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. But I thought that to say everything came into existence at t=0 is not scientifically supported; that the universe is eternal and matter is finite... . What is scientifically supported is space time matter as we know it came into being from the big bang, right? Isn't energy eternal and it is probable that some eternal substance exists and is behind the cause of the universe from the big bang? This doesn't mean matter poofed from nothing, right? It reminds me of an online discussion I've read recently (Bold vs Italics): "The universe cannot be eternal, philosophically and scientifically." Yes it can. You think God can be eternal so why can't I say the sum of existence is eternal? Matter isn't eternal, but it's a false dichotomy to say either God exists eternally or matter exists eternally.actual infinites don't exist in the physical universe; God is actually infinite but transcends the physical universe and is not bound there-in or there-by. You have no basis to say what the universe may include. Your equivicating my definition of the universe which is all that exists with your limited idea of what you call the universe, space, matter and time. Also you haven't proven that finitude of time correlates with ontological beginning of the physical universe. Two problems that apologists readily ignore in favor of attacking a straw man atheism.Quoting Al
Al Moritz
Indeed. Eternal matter
An essential demand on eternal matter would have to be that it does not have to obey the second law of thermodynamics (by the way, this demand also holds for the “re-set” of a potential cyclic universe upon each bounce). Otherwise, what use would be eternal matter if it had all run down into an undifferentiated mush that would not have the thermal/motional energy anymore to produce universes? In the ekpyrotic model (or one may think of equivalent other options if string theory, upon which it is based, will be refuted), for example, we have the birth of our universe from a collision of membranes (branes) in multi-dimensional space.
Where does the energy of collision come from if the second law of thermodynamics holds in an eternal universe? It could never self-renew, and if it cannot, it would eventually run down into thermal randomness, and one would be forced to ask the question: where did it come from in its original “fresh” state?
If the postulated eternal matter once had to be in an original “fresh” state, it cannot be self-sufficient and eternal after all, certainly not in a state that eternally can produce universes. Thus it would beg the question for an originator of this matter anyway.
Of course, energy is equivalent to matter, but analysis shows that this does not solve the "moving" problem: the universe becomes less and less capable of converting matter to energy (one can see this by analyzing the issue of star formation and star burning).
Certainly, one may believe in the magic of a wider universe where the second law of thermodynamics does not hold, but I find this unlikely (we know how matter behaves *)) and we probably can never observe this, given the absolute observational limits in cosmology (the visible horizon and the particle horizon). Here, blind faith needs to replace observational evidence.
*) Yes, we know that all matter moves at all times on the microscopic particle level, but this is different from eternal movement with always fresh kinetic energy on the macroscopic level. And a universe (a large closed system of spacetime and matter) for which the second law of thermodynamics holds will become cooler and cooler over time, restricting also microscopic movement more and more.
Eternal field
An alternative to eternal matter would be an eternal field. Think of the quantum vacuum.
We know that quantum vacua can produce virtual particles and anti-particles that, however, eliminate each other in the tiniest fractions of milliseconds. Some extrapolate in wild speculation that the universe could have arisen in a similar manner from a quantum vacuum, from almost nothing. However, we do not have any theoretical, and even less experimental, evidence that would make a link between such hugely different events like the humble appearance of a tiny virtual particle and an event of such unbelievable magnitude of energy as the Big Bang (the universe was 10E32 Kelvin hot a miniscule fraction of a second after its the beginning, that is “10 with 32 zeros behind it” Kelvin, or billions of billions of billions and more Kelvin). It is pure, wild speculation that has little to do with science – and all with fantasy run amok.
If this kind of events could happen “just like that”, why haven’t we observed the birth of another universe within the 15 billion years time that ours exist? (Yeah, it is argued that it creates its own spacetime and thus vanishes into other dimensions, but it is hard to believe that the event would leave no trace.) Certainly, there will be those that say that in eternal fields anything can happen at some point, unlikely as it may seem, but this is the ultimate “just-so” story that you can tell a senile grandma but not me. Embarrassingly, atheists seem to seriously consider such “just-so” stories.
Eternal matter that does not obey the second law of thermodynamics, and eternal fields that can produce sudden high-energy events from “nowhere”? All those “scientific” scenarios are not scientific at all, they are modern fairytales dressed up in the language of science. Atheists, however, would never concede that they believe in fairytales, they just accuse believers of doing so.
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Post by knowingthomas on May 6, 2009 18:55:29 GMT
Isn't the existence of inflation support for the existence for the multiverse?
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Post by humphreyclarke on May 6, 2009 19:06:11 GMT
Isn't the existence of inflation support for the existence for the multiverse? Short answer is no. Long answer is that inflation is still an unproven theory which is extremely hard to test (there is going to be an attempt to confirm it in 2010 by looking for gravitational waves). Some scientists, e.g Roger Penrose don't think a lot of it. Even if inflation were proven this would not of itself provide support for a multiverse. The reason a multiverse is proposed for inflation is that it requires serious amounts of fine tuning; hence the idea of chaotic inflation. Therefore it would imply a multiverse in the same way the value of the cosmological constant implys a multiverse (i.e the conditions are too special). How you would test chaotic inflation, I have absolutely no idea.
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Post by knowingthomas on May 6, 2009 19:15:14 GMT
That's odd. I thought the vast majority of scientists accept inflation in some degree?
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Post by humphreyclarke on May 6, 2009 19:51:50 GMT
That's odd. I thought the vast majority of scientists accept inflation in some degree? Cosmic inflation a good theory and it explains the flatness of the universe. It's not proven yet and it has a few detractors with competing models. Chaotic inflation (which would create a multiverse) is pure speculation although from the hype you would think it was proven already. I suspect it's untestable, meaning its not really a scientific idea at all You should read Peter Woit's blog for the current state of cosmology: www.math.columbia.edu/~woit/wordpress/
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Post by unkleE on May 6, 2009 21:48:30 GMT
You should read Peter Woit's blog for the current state of cosmology: 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. I try to keep up a general interest in cosmology, so I read Peter Woit's blog with some interest (and not a little incomprehension). It seems like cosmology is polarised in a similar way to the atheist-theist debate as we have discussed elsewhere on this forum. But whereas one might expect polarisation on metaphysical matters, one might fondly hope that physicists would base their conclusions on objective evidence, and would therefore be close to agreement on things. But instead the string theorists and the anti-string theorists seem to take things very personally. I wonder how the game is going, what is the score and which way the tide is running? It will be interesting to follow the ebb and flow of the debate, and perhaps see these matters resolved. Thanks for the link.
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Post by knowingthomas on May 7, 2009 6:11:55 GMT
Alright I guess that clears up a lot, yet two questions remain:
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?
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?
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Post by unkleE on May 7, 2009 7:12:14 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. My understanding is that most of the so-called fine-tuning constants relate to the formation of a suite of different atoms (not just Hydrogen and Helium) and the formation of clumps of matter like stars and planets, etc, and the continuation of these for a significant time. For example, Martin Rees in "Just Six Numbers" lists six (yes!) constants or ratios that have to be "just right", and most of these relate to the structure of the universe, etc, and only one or two relate directly to life forming. So he seems to be saying that the odds of a universe with structure lasting very long are very small, and the odds of life forming are not much smaller. It is true that Victor Stenger produced a model, using only a few parameters, which claimed that it was quite possible in probability terms that the universe would last sufficiently long for life to form, but I don't think many cosmologists have accepted the validity of this work. If we can conceive of life forming in space in a relatively short time, then that answer would be less convincing also. I guess it all depends on how wildly speculative we want to be about the possible variations from what we see.
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