On Mon, Nov 2, 2015 at 1:20 PM, Pierz <[email protected]> wrote: > > > On Monday, November 2, 2015 at 5:27:04 AM UTC+11, telmo_menezes wrote: > >> >> >> On Sun, Nov 1, 2015 at 3:14 AM, Pierz <[email protected]> wrote: >> >>> >>> >>> On Saturday, October 31, 2015 at 11:20:32 PM UTC+11, telmo_menezes wrote: >>>> >>>> >>>> >>>> On Sat, Oct 31, 2015 at 5:19 AM, Pierz <[email protected]> wrote: >>>> >>>>> >>>>> >>>>> On Saturday, October 31, 2015 at 1:01:08 PM UTC+11, Brent wrote: >>>>>> >>>>>> >>>>>> >>>>>> On 10/30/2015 5:39 AM, Pierz wrote: >>>>>> >>>>>> So imagine a guy washed up on a small desert island after a plane >>>>>> crash. Unfortunately during the plane crash he suffered a traumatic >>>>>> injury >>>>>> which caused him to completely lose his memory. He wakes up on the sure >>>>>> without the faintest clue about who he is or where he comes from. He >>>>>> doesn't even remember that there are other people in the world and that >>>>>> he >>>>>> was born of a mother and father. After sorting out his immediate survival >>>>>> needs, being a philosophical type, he begins to wonder about his own >>>>>> origins. He begins to speculate about the what conditions might have >>>>>> given >>>>>> rise to him and the island he finds himself on. >>>>>> >>>>>> Without the benefit of the memory of any scientific knowledge, he is >>>>>> struck by the strangeness of the fact that the world he finds himself in >>>>>> seems so well-adapted to him - or he to it. Isn't it marvellous, he >>>>>> reasons, that when I feel this particular unpleasant sensation of dryness >>>>>> (which we, but not he, would call "thirst"), it happens that there is >>>>>> some >>>>>> abundant substance I can locate that, if conveyed into my mouth, relieves >>>>>> that sensation? Isn't it astonishing that I have these dextrous digital >>>>>> appendages that seem so perfectly made for constructing a shelter, or >>>>>> making and throwing a spear? How to explain it? >>>>>> >>>>>> Being more of a mathematician than a naturalist by nature, he reasons >>>>>> that perhaps the explanation is simply this: the ocean that he sees that >>>>>> appears to extend indefinitely in all directions is in fact infinite. And >>>>>> scattered across that infinite ocean there are other islands. He can see >>>>>> at >>>>>> least a couple from where he is, so if the ocean is infinite there would >>>>>> end up being an infinity of such islands. And if there are an infinite >>>>>> number of such islands, then all possible arrangements of matter will >>>>>> eventually form by chance. If they happen to form something conscious - >>>>>> and >>>>>> conscious enough to reason about its origins - then that conscious being >>>>>> will be required to be complex enough and well adapted enough to the >>>>>> stuff >>>>>> around it that it can maintain its own integrity long enough to form such >>>>>> deep thoughts. >>>>>> >>>>>> >>>>>> Interestingly, as Lawrence Krauss and Sean Carroll both mention in >>>>>> their popular lectures, in the far future the accelerating expansion of >>>>>> the >>>>>> universe will leave the Milkyway alone with no other galaxy within the >>>>>> Hubble sphere. The universe will appear to our sucessors, if there are >>>>>> any, completely empty with a lone island of stars and matter. >>>>>> >>>>>> >>>>>> OK, there are still some holes in his Theory of Everything (where did >>>>>> the ocean come from?) but a man has to draw the line *somewhere*. He >>>>>> is smart enough to see the lurking possibility of infinite regress and >>>>>> skirt around it. With this he is satisfied and settles back to eat >>>>>> another >>>>>> coconut, convinced he has found a coherent explanation of his own >>>>>> existence... >>>>>> >>>>>> The problem with his impoverished account, of course, is that it >>>>>> misses a vast amount of structure in the world. The line he has drawn to >>>>>> stave off infinite explanatory regress is clearly far too high in the >>>>>> hierarchy of complexity, but because of the limited range of his >>>>>> experience, he is unlikely to see that. If he could witness mating and >>>>>> birth, for instance, he might start to wonder if he hadn't been a little >>>>>> hasty in his invocation of infinite permutation as an explanatory >>>>>> principle. With sufficient exposure to time and diverse biology, he might >>>>>> start to wonder about the role of an *evolutionary* process. >>>>>> >>>>>> It's clear how much better the evolutionary explanation is because, >>>>>> armed with it, he might be able to make predictions. He might be able to >>>>>> foresee, for instance, that his body should have robust mechanisms for >>>>>> dealing with normal environmental vicissitudes. Suffering his first minor >>>>>> wound, he might predict that the injury would heal. On the other hand, >>>>>> with >>>>>> the "infinite permutations theory", he could predict nothing at all. >>>>>> Though >>>>>> it offers a somewhat satisfying conceptual neatness, it also lacks any >>>>>> predictive power whatsoever. >>>>>> >>>>>> You can see perhaps see where I'm going with this. I tend to believe >>>>>> in a multiverse. But I also tend to believe that as an explanation of >>>>>> fine-tunedness *per se*, the combination of a multiverse with the >>>>>> anthropic principle is scientifically and philosophically bankrupt. I >>>>>> believe that we are like desert island amnesiacs, lacking the breadth of >>>>>> observation that we would need in order to see the correct picture of how >>>>>> fine tuning arises in our local environment. Lee Smolin's theory of an >>>>>> evolutionary universe gets closer, but suffers from the serious flaw that >>>>>> he sees universes evolving towards black-hole production, which is only >>>>>> incidentally or co-incidentally related to life-friendliness. >>>>>> >>>>>> My hunch is that the true explanation of fine-tuning (and hence of >>>>>> the physical laws we observe) is one that involves our universe being >>>>>> embedded in much larger multiversal structures and processes which we >>>>>> probably can't even guess at with our current technological and >>>>>> theoretical >>>>>> apparatus. The resort to "all possible structures" flattens out infinity >>>>>> to >>>>>> a single dimension the same way that the castaway amnesiac flattens out >>>>>> infinity to the level of the ocean. I suspect the truth is much deeper >>>>>> and >>>>>> more complex and that the fined universe we see is a result of a kind of >>>>>> deep computational process in the same way that biological complexity is >>>>>> the end result of a long computational process. >>>>>> >>>>>> >>>>>> An interesting viewpoint. However, I think that "fine-tuning" is a >>>>>> problem that was invented to satisfy a solution. Smolin had an >>>>>> interesting >>>>>> evolutionary theory of cosmogony, but it turned out to be empirically >>>>>> falsified because this universe doesn't have the physical parameters to >>>>>> maximize black hole production. >>>>>> >>>>>> Hunches that there is a much deeper truth that we can't even guess >>>>>> are like "brain in a vat" ideas in that they lead nowhere. >>>>>> >>>>> >>>>> Maybe so. But there's an element to my thought experiment I didn't >>>>> quite spell out. The castaway faces a similar problem in explaining his >>>>> organismic adaptation as we face in explaining "fine tuning" (which I >>>>> don't >>>>> agree is a pseudo-problem - there are many physicists who remain resistant >>>>> to the multiverse + anthropic principle explanation). A developmental or >>>>> selection hypothesis makes some predictions about adaptation - wound >>>>> healing is an example - which the infinite islands hypothesis does not. >>>>> Similarly the multiverse explanation of fine tuning always explains >>>>> exactly >>>>> what *is* and nothing more. It explains all the fine tuning we've >>>>> discovered, but none that we might discover in the future. For example, it >>>>> is quite incredible that there happens to be a substance with all the >>>>> life-supporting properties of water, and an element carbon that is capable >>>>> of such extraordinarily complex chemical combinations. By the >>>>> multiverse/anthropic explanation, we'd expect to find more than a few such >>>>> remarkable coincidences in any life-supporting environment. But now let's >>>>> imagine a society far in the future which has discovered a whole range of >>>>> further remarkable fine-tunings which have supported or enabled a much >>>>> more >>>>> advanced society. They might find for example a certain fine-tuning >>>>> principle which shows that the probability of a planet being hit by a >>>>> mass-extinction-causing asteroid is finely tuned to support the >>>>> development >>>>> of intelligent societies. Perhaps evolution tends to follow a trajectory >>>>> towards the evolution of oversized predators which are then typically >>>>> wiped >>>>> out by collision events because they do not have the intelligence to >>>>> prevent them. This then allows the development of an intelligent species >>>>> which is capable of predicting and preventing such collisions. Now of >>>>> course I'm not suggesting this *is* the case, or that it necessarily >>>>> makes a heap of sense as an example (I made it up just then), but if we >>>>> were able to visit many, many inhabited planets and we saw the same >>>>> pattern >>>>> over and over, we might then start to say, "Wow, it's kind of remarkable >>>>> that there always seems to be enough time to develop a society capable of >>>>> gravitational towing technology. If there was just a slightly higher >>>>> frequency of collisions in a typical solar system, then most intelligent >>>>> species would be wiped out like the dinosaurs before they reached the >>>>> stage >>>>> to be able to prevent it." So there you have an example of a newly >>>>> discovered piece of fine-tuning that we would not predict from the theory >>>>> today. On its own it might not be all that convincing, but if enough >>>>> similar examples accumulated, one might start to find it fishy and wonder >>>>> why we kept getting so "lucky". This would point to something beyond the >>>>> huge sample + observer selection hypothesis. It would suggest that the >>>>> universe was an example of something that had been selected or evolved, >>>>> with life central to that selection process. So, my idea might not lead >>>>> nowhere after all. It will take a long time to verify, but my hunch is >>>>> that >>>>> fine tunings of precisely the nature I've described (well, not the >>>>> specific >>>>> example) *will* be found. A sufficient number would ultimately >>>>> falsify the purely anthropic explanation of fine-tuning. >>>>> >>>> >>>> Hi Pierz, >>>> >>>> This is really interesting stuff. I also tend to think that evolution >>>> will turn out to be superseded by some more general theory, in the same >>>> fashion that happened to classical physics. It will remain viable in a >>>> narrow sense, but not the whole story. >>>> >>>> But to play devil's advocate, this sort of intuition seems to come from >>>> a sense of vastness of the universe and even greater vastness of a >>>> multiverse. Something I sometimes think about is that this sense might be >>>> misguided. It is true that there enormous distances and mind-blowing >>>> numbers of galaxies with mind-blowing numbers of stars, but what if we are >>>> taking the concepts of distance and repetition too seriously? What I mean >>>> is this: instead of looking at the universe spatially, what if we looked at >>>> it in terms of information content? >>>> >>>> Suppose we wanted to store the current state of the universe in some >>>> very powerful computer (that would, of course, have to exist in some other, >>>> larger universe, whatever that means -- this is just a thought experiment). >>>> We could apply a compression algorithm. There is not need to represent >>>> large amounts of empty space or repetition as a dense matrix. Instead we >>>> could do something similar to what is done to compress images or sound. In >>>> this compressed information space, I wonder how much the perceived "sized" >>>> of the earth in comparison to the rest of the universe would change. I >>>> suspect that, from this perspective, the earth is actually huge, because it >>>> is so complex. What if, looking at things through this lens, the earth >>>> turns out to be "most of what there is" in information space? Would this >>>> change your intuitions somehow? >>>> >>> >>> Interesting, but you may be running afoul of some fuzziness in the >>> notion of "information content". What you seem to be referring to is >>> complexity rather than information, which is typically equated with entropy. >>> >> >> Ok, good point. I was thinking more about Kolmogorov complexity rather >> than entropy -- so my compression algorithm would be a generator program as >> opposed to something like run length encoding or Fourier transforms. >> >> >>> If you want to reproduce a system by storing information about it, then >>> a disordered system like the state of the rings of Saturn can typically not >>> be compressed at all, whereas an ordered system contains regularities which >>> allow it to be described by some simplifying rules which can be used to >>> compress the information about the system. >>> >> >> I wonder if this picture changes if one considers the distributions of >> possible states of the rings of Saturn vs the distribution of all possible >> states of the Earth, within some range. >> >> >>> A jpg compression of a field of pure colour "noise" will be the same >>> size as the uncompressed file. But we need to be careful even here, because >>> I have my doubts that reality can actually be compressed "losslessly" at >>> all. Even empty space is a froth of virtual particles which contribute to >>> the quantum state of the universe as a whole. You might be able to write >>> off huge tracts of the universe as "uninteresting" (for example you could >>> reduce it to x quadrillion cubic light years of emptiness) but the universe >>> may beg to differ. >>> >> >> It is true that true randomness is not compressible, but it is also true >> that a program that describes how to generate one of the possible states of >> a cubic light years of emptiness according to their probability of >> occurrence is probably orders of magnitude smaller that the program needed >> to generate one of the possible states of the planet Earth in 2015. >> >> >>> >>> Anyway, ignoring these quibbles and accepting that the earth is, from a >>> "deep computation" point of view, vastly larger in a certain kind of >>> information space than much of the rest of the universe, I very much doubt >>> it is *unique *in this respect. Richard Dawkins has argued that it >>> might be (in "The Blind Watchmaker" IIRC?), but his argument is flawed. >>> Essentially he says that we don't know the probability of life arising on a >>> given planet, but given that there are *n *planets in the universe, >>> then the probability might be as low as 1/*n*. If it *were* of order 1/*n, >>> *then it is likely there is only one, which would have to be ours, >>> because here we are! However, this begs the question. Given that *n* is >>> an extremely large number (about 10^24), then the *probability of the >>> probability* of life occurring on a given planet just happening to be >>> close to exactly 1/*n* is very, very small. >>> >> >> Humm... I think there are some problems with this argument. If you allow >> for any type of multiverse, then you don't know how many universes contain >> a planet like Earth, so it becomes impossible to estimate the probability. >> Say you know n, and you know for sure that we are in the only planet with >> life in the universe, but you don't know the number of universes with >> Earths, then p could be anything in ]0, 1/n]. In this case I don't think >> you can apply this sort of probability-of-probability reasoning. >> > > Actually you're just strengthening my argument. The Blind Watchmaker came > out a long time ago - before multiverses had much traction - so Dawkins was > proceeding from the assumption that the observable universe was pretty much > it. If the number of planets in existence is much larger than the ~10^24 in > the observable universe, then the claim that there is only one with life > becomes an even stronger one - and hence one requiring equally strong > supporting evidence. It's asserting that the probability lies in an > *extremely* narrow range. But we have no idea what the probability is, so > such an assertion is unjustified. If there were only ten planets in the > universe, then clearly the claim that ours is the only one with life is a > much weaker claim than if there were a googol of them! Unless I don't > understand your point? >
My point is that, there could be a very large proportion of non-observable universes with zero instances of life. This would mean that the probability is so small that, given a universe with life, it is likely to be a single instance. But since we do not know the proportion of non-observable universes with zero instances of life, we cannot estimate the probability at all. Notice that I am not claiming this to be the case, just that it is a possible scenario. It is really hard to do statistical inference with just one data point :) > > > >> >> >>> >>> Furthermore, cosmology now points to an extremely large and possibly >>> spatially infinite universe. In that context, the idea that this is the >>> only "island" is vanishingly small to non-existent. >>> >> >> I agree. >> >> >>> >>> When I was a kid I remember looking up at the stars and wondering if we >>> mightn't be a "germ in the left leg of God." In other words, what vast >>> structures of time, space and possibly mind might we be a part of without >>> our being aware of it? It's incredible that humanity has seen as far and as >>> deeply as it has, but in the context of "infinity in all directions", we >>> should also be humble enough to recognise that we are still microscopic >>> germs and the farthest we can see may still be immensely limited. >>> >> >> Agreed. My intuition is that there are other advanced civilizations, but >> probably very far away in space and/or time. >> >> >> >>> >>>> Best, >>>> Telmo. >>>> >>>> >>>>> >>>>> >>>>>> >>>>>> Brent >>>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "Everything List" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to [email protected]. >>>>> To post to this group, send email to [email protected]. >>>>> Visit this group at http://groups.google.com/group/everything-list. >>>>> For more options, visit https://groups.google.com/d/optout. >>>>> >>>> >>>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Everything List" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To post to this group, send email to [email protected]. >>> Visit this group at http://groups.google.com/group/everything-list. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
