Comments on: OO’s and BB’s http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/ Random samplings from a universe of ideas. Mon, 09 Nov 2009 09:26:25 -0600 http://wordpress.org/?v=2.8.4 hourly 1 By: A Glimpse Into Boltzmann’s Actual Brain | Cosmic Variance | Discover Magazine http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-78385 A Glimpse Into Boltzmann’s Actual Brain | Cosmic Variance | Discover Magazine Mon, 08 Jun 2009 16:35:52 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-78385 [...] heard the “Boltzmann’s Brain” argument (here and here, for example). It’s a simple idea, which is put forward as an argument against the notion [...] [...] heard the “Boltzmann’s Brain” argument (here and here, for example). It’s a simple idea, which is put forward as an argument against the notion [...]

]]> By: A Glimpse Into Boltzmann’s Actual Brain | Cosmic Variance http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-25303 A Glimpse Into Boltzmann’s Actual Brain | Cosmic Variance Fri, 04 May 2007 05:04:20 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-25303 [...] You’ve heard the “Boltzmann’s Brain” argument (here and here, for example). It’s a simple idea, which is put forward as an argument against the notion that our universe is just a thermal fluctuation. If the universe is an ordinary thermodynamic system in equilibrium, there will be occasional fluctuations into low-entropy states. One of these might look like the Big Bang, and you might be tempted to conclude that such a process explains the arrow of time in our universe. But it doesn’t work, because you don’t need anything like such a huge fluctuation. There will be many smaller fluctuations that do just as well; the minimal one you might imagine would be a single brain-sized collection of particles that just has time to look around and go Aaaaaagggghhhhhhh before dissolving back into equilibrium. (These days a related argument is being thrown around in the context of eternal inflation — not exactly the same, because we’re not assuming the ensemble is in equilibrium, but similar in spirit.) [...] [...] You’ve heard the “Boltzmann’s Brain” argument (here and here, for example). It’s a simple idea, which is put forward as an argument against the notion that our universe is just a thermal fluctuation. If the universe is an ordinary thermodynamic system in equilibrium, there will be occasional fluctuations into low-entropy states. One of these might look like the Big Bang, and you might be tempted to conclude that such a process explains the arrow of time in our universe. But it doesn’t work, because you don’t need anything like such a huge fluctuation. There will be many smaller fluctuations that do just as well; the minimal one you might imagine would be a single brain-sized collection of particles that just has time to look around and go Aaaaaagggghhhhhhh before dissolving back into equilibrium. (These days a related argument is being thrown around in the context of eternal inflation — not exactly the same, because we’re not assuming the ensemble is in equilibrium, but similar in spirit.) [...]

]]> By: What I Believe But Cannot Prove | Cosmic Variance http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-25360 What I Believe But Cannot Prove | Cosmic Variance Wed, 11 Apr 2007 20:51:02 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-25360 [...] The search for certainty in empirical knowledge is a chimera. I could always be a brain in a vat, or teased by an evil demon, or simply an AI program running on somebody else’s computer — fed consistently misleading “sense data” that led me to incorrect conclusions about the true nature of reality. Or, to put a more modern spin on things, I could be a one of Boltzmann’s Brains — a thermal fluctuation, born spontaneously out of a thermal bath with convincing (but thoroughly incorrect) memories of the past. But — here is the punchline — it makes no sense to act as if any of those is the case. By “makes no sense” we don’t mean “can’t possibly be true,” because any one of those certainly could be true. Instead, we mean that it’s a cognitive dead end. Maybe you are a brain in a vat. What are you going to do about it? You could try to live your life in a state of rigorous epistemological skepticism, but I guarantee that you will fail. You have to believe something, and you have to act in some way, even if your belief is that we have no reliable empirical knowledge about the world and your action is to never climb out of bed. On the other hand, putting aside the various solipsistic scenarios and deciding to take the evidence of our senses (more or less) at face value does lead somewhere; we can make sense of the world, act within it and see it respond in accordance with our understanding. That’s both the best we can hope for, and what the world does as a matter of fact grant us; that’s why science works! [...] [...] The search for certainty in empirical knowledge is a chimera. I could always be a brain in a vat, or teased by an evil demon, or simply an AI program running on somebody else’s computer — fed consistently misleading “sense data” that led me to incorrect conclusions about the true nature of reality. Or, to put a more modern spin on things, I could be a one of Boltzmann’s Brains — a thermal fluctuation, born spontaneously out of a thermal bath with convincing (but thoroughly incorrect) memories of the past. But — here is the punchline — it makes no sense to act as if any of those is the case. By “makes no sense” we don’t mean “can’t possibly be true,” because any one of those certainly could be true. Instead, we mean that it’s a cognitive dead end. Maybe you are a brain in a vat. What are you going to do about it? You could try to live your life in a state of rigorous epistemological skepticism, but I guarantee that you will fail. You have to believe something, and you have to act in some way, even if your belief is that we have no reliable empirical knowledge about the world and your action is to never climb out of bed. On the other hand, putting aside the various solipsistic scenarios and deciding to take the evidence of our senses (more or less) at face value does lead somewhere; we can make sense of the world, act within it and see it respond in accordance with our understanding. That’s both the best we can hope for, and what the world does as a matter of fact grant us; that’s why science works! [...]

]]> By: Stathis Papaioannou http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-25302 Stathis Papaioannou Mon, 05 Mar 2007 11:47:32 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-25302 Torbjörn> This is exactly my point - without the possibility of an external observer no one will know if the copying succeeded. The clone will only know of themselves, and they can't tell if they were successfully copied or not. And how would you know you were the same person if you were kidnapped and taken to a distant place in your sleep tonight? Would you need to check with someone else? Torbjörn> This is exactly my point – without the possibility of an external observer no one will know if the copying succeeded. The clone will only know of themselves, and they can’t tell if they were successfully copied or not.

And how would you know you were the same person if you were kidnapped and taken to a distant place in your sleep tonight? Would you need to check with someone else?

]]> By: Torbjörn Larsson http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-25300 Torbjörn Larsson Sun, 04 Mar 2007 23:45:06 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-25300 Stathis: <blockquote> Moreover, we do know that our consciousness can survive copying because it happens all the time: most of the atoms in your brain are replaced over a matter of weeks to months. </blockquote> Well, not exactly. Many of our molecules are replaced by being broken down and reused. Metabolism supplies and removes some atoms when this happens. But much of our brain is static on the working cellular level, i.e. synapses and gate channels are added and removed but the neurons may not be replaced. But all that is besides the point, You have not explained how you will copy a brain close enough to be functionally equivalent with the original while <i>continuing with the same state</i> as when cloned. You are just claiming that it is possible. But that is not a demonstration. <blockquote> it isn't a problem from your point of view if you are the one being copied </blockquote> This is exactly my point - without the possibility of an external observer no one will know if the copying succeeded. The clone will only know of themselves, and they can't tell if they were successfully copied or not. But I think the problem with our communication is solved, if there ever was one. You are repeating your claims without addressing my arguments. I don't think it is meaningful to continue. Stathis:

Moreover, we do know that our consciousness can survive copying because it happens all the time: most of the atoms in your brain are replaced over a matter of weeks to months.

Well, not exactly. Many of our molecules are replaced by being broken down and reused. Metabolism supplies and removes some atoms when this happens.

But much of our brain is static on the working cellular level, i.e. synapses and gate channels are added and removed but the neurons may not be replaced.

But all that is besides the point, You have not explained how you will copy a brain close enough to be functionally equivalent with the original while continuing with the same state as when cloned.

You are just claiming that it is possible. But that is not a demonstration.

it isn’t a problem from your point of view if you are the one being copied

This is exactly my point – without the possibility of an external observer no one will know if the copying succeeded. The clone will only know of themselves, and they can’t tell if they were successfully copied or not.

But I think the problem with our communication is solved, if there ever was one. You are repeating your claims without addressing my arguments. I don’t think it is meaningful to continue.

]]> By: island http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-25294 island Sat, 03 Mar 2007 20:12:03 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-25294 Elliot, I think that Lee's idea about an inherent time asymmetry necessitates "an underlying principle or law that favors the emergence of complexity", in terms of an energy conservation law that guarantees that the second law of thermodynamics never be violated, such as the one that is discussed here, in context with Richard Dawkins' own ideas about the "anti-chance mechanism of natural selection": http://pespmc1.vub.ac.be/ASYMTRANS.html ... and as it is illustrated, here: http://pespmc1.vub.ac.be/ASYMILL.html ... and on my blog, where my own ideas about <a href="http://evolutionarydesign.blogspot.com/2007/02/our-darwinian-universe.html" rel="nofollow">"Our Darwinian Universe"</a> are nearly identical, although less complex by orders of magnitude. The high energy physics mechanism for this is discussed in the following linked article, and many other places on <a href="http://evolutionarydesign.blogspot.com/" rel="nofollow">my website</a>. This is the same mehanism that is used in inflationary models, where mass can be created at the expense of a large negative gravitational energy following from expansion, except that the universe is held flat and stable as expansion accelerates toward the next big bang: http://www.lns.cornell.edu/spr/2006-02/msg0073320.html Elliot, I think that Lee’s idea about an inherent time asymmetry necessitates “an underlying principle or law that favors the emergence of complexity”, in terms of an energy conservation law that guarantees that the second law of thermodynamics never be violated, such as the one that is discussed here, in context with Richard Dawkins’ own ideas about the “anti-chance mechanism of natural selection”:

http://pespmc1.vub.ac.be/ASYMTRANS.html

… and as it is illustrated, here:

http://pespmc1.vub.ac.be/ASYMILL.html

… and on my blog, where my own ideas about “Our Darwinian Universe” are nearly identical, although less complex by orders of magnitude.

The high energy physics mechanism for this is discussed in the following linked article, and many other places on my website. This is the same mehanism that is used in inflationary models, where mass can be created at the expense of a large negative gravitational energy following from expansion, except that the universe is held flat and stable as expansion accelerates toward the next big bang:

http://www.lns.cornell.edu/spr/2006-02/msg0073320.html

]]> By: Stathis Papaioannou http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-25344 Stathis Papaioannou Sat, 03 Mar 2007 01:48:01 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-25344 Torbjörn Larsson >Therefore you must demonstrate that the deviations will still make a close enough copy to be a mind clone. It may be possible, since the we seem robust enough. But we don't know. So you can't claim ad hoc that it is possible, it isn't exactly like copying a brick by dimension but it is like copying every sand particle and their binding forces in every detail. The brick has a particular function and a particular engineering tolerance for that function; you don't need to specify it down to the quantum level. If the brain had an engineering tolerance of zero, random thermal motion in our heads would kill us instantly. Moreover, we do know that our consciousness can survive copying because it happens all the time: most of the atoms in your brain are replaced over a matter of weeks to months. Torbjörn Larsson >What I mean is that even if it would be impossible of making a constructed copy, it would not preclude us or the universe to build bounded or unbounded many different brains. By chance someone might (will, in the later case) be a perfect copy of you and your thoughts from some moment and forward. >But we can't tell which one, because if it is impossible to make an exact enough copy, we can't compare them either. This seems to preclude any possibility of you (being in the bounded category) making an exact copy and be certain of it, ie observe it. That would be a censorship principle. For an external observer that is so, but it isn't a problem from your point of view if you are the one being copied. If you are instantaneously disintegrated and a sufficiently close copy of you is made within the event horizon of a black hole, no-one will ever be able to find the copy but you will suddenly find yourself as if magically transported there. Torbjörn Larsson >Therefore you must demonstrate that the deviations will still make a close enough copy to be a mind clone. It may be possible, since the we seem robust enough. But we don’t know. So you can’t claim ad hoc that it is possible, it isn’t exactly like copying a brick by dimension but it is like copying every sand particle and their binding forces in every detail.

The brick has a particular function and a particular engineering tolerance for that function; you don’t need to specify it down to the quantum level. If the brain had an engineering tolerance of zero, random thermal motion in our heads would kill us instantly. Moreover, we do know that our consciousness can survive copying because it happens all the time: most of the atoms in your brain are replaced over a matter of weeks to months.

Torbjörn Larsson >What I mean is that even if it would be impossible of making a constructed copy, it would not preclude us or the universe to build bounded or unbounded many different brains. By chance someone might (will, in the later case) be a perfect copy of you and your thoughts from some moment and forward.

>But we can’t tell which one, because if it is impossible to make an exact enough copy, we can’t compare them either. This seems to preclude any possibility of you (being in the bounded category) making an exact copy and be certain of it, ie observe it. That would be a censorship principle.

For an external observer that is so, but it isn’t a problem from your point of view if you are the one being copied. If you are instantaneously disintegrated and a sufficiently close copy of you is made within the event horizon of a black hole, no-one will ever be able to find the copy but you will suddenly find yourself as if magically transported there.

]]> By: Torbjörn Larsson http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-25306 Torbjörn Larsson Thu, 01 Mar 2007 21:15:21 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-25306 <blockquote> Wow, what a complicated sentence that was! </blockquote> I'm sorry, we do seem to have a communication problem which I cause, not least because I'm too tired when I have time to answer. <blockquote> Certainly it would be very difficult, like simulating the weather, but how is it possible that a neuron will do something that is uncomputable? </blockquote> My point here is that it seems to be (even classically) impossible in theory to copy a systems Hamiltonian perfectly. So it isn't only the terribly difficult matter of copying the systems biochemical wetware and current state, or the even worse difficulty of copying into another type of system, but it is impossible to make a perfect copy. Therefore you must demonstrate that the deviations will still make a close enough copy to be a mind clone. It may be possible, since the we seem robust enough. But we don't know. So you can't claim ad hoc that it is possible, it isn't exactly like copying a brick by dimension but it is like copying every sand particle <b>and their binding forces in every detail</b>. <blockquote> since the possible improbability of deterministically copying a brain doesn't preclude the stochastic probability of doing it. </blockquote> What I mean is that even if it would be impossible of making a constructed copy, it would not preclude us or the universe to build bounded or unbounded many different brains. By chance someone might (will, in the later case) be a perfect copy of you and your thoughts from some moment and forward. But we can't tell which one, because if it is impossible to make an exact enough copy, we can't compare them either. This seems to preclude any possibility of you (being in the bounded category) making an exact copy and be certain of it, ie observe it. That would be a censorship principle.

Wow, what a complicated sentence that was!

I’m sorry, we do seem to have a communication problem which I cause, not least because I’m too tired when I have time to answer.

Certainly it would be very difficult, like simulating the weather, but how is it possible that a neuron will do something that is uncomputable?

My point here is that it seems to be (even classically) impossible in theory to copy a systems Hamiltonian perfectly. So it isn’t only the terribly difficult matter of copying the systems biochemical wetware and current state, or the even worse difficulty of copying into another type of system, but it is impossible to make a perfect copy.

Therefore you must demonstrate that the deviations will still make a close enough copy to be a mind clone. It may be possible, since the we seem robust enough. But we don’t know. So you can’t claim ad hoc that it is possible, it isn’t exactly like copying a brick by dimension but it is like copying every sand particle and their binding forces in every detail.

since the possible improbability of deterministically copying a brain doesn’t preclude the stochastic probability of doing it.

What I mean is that even if it would be impossible of making a constructed copy, it would not preclude us or the universe to build bounded or unbounded many different brains. By chance someone might (will, in the later case) be a perfect copy of you and your thoughts from some moment and forward.

But we can’t tell which one, because if it is impossible to make an exact enough copy, we can’t compare them either. This seems to preclude any possibility of you (being in the bounded category) making an exact copy and be certain of it, ie observe it. That would be a censorship principle.

]]> By: Stathis Papaioannou http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-25327 Stathis Papaioannou Tue, 27 Feb 2007 13:54:38 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-25327 SP> If it is possible in theory to preserve brain function by replacing each neuron with a computer chip, that is if the brain is Turing emulable, then a particular brain program could run on an infinite number of general purpose computers. Torbjörn Larsson> But this possibility is what I claimed earlier what you must establish. I can't see that you have moved your argument. Brains are made of matter which follows the well-understood laws of chemistry. Certainly it would be very difficult, like simulating the weather, but how is it possible that a neuron will do something that is uncomputable? Roger Penrose has had to speculate on an uncomputable theory of quantum gravity just to keep the brain special, but he is almost alone in his position. Torbjörn Larsson> I think there is some confusion here, possibly on my part, since the possible improbability of deterministically copying a brain doesn't preclude the stochastic probability of doing it. Wow, what a complicated sentence that was! stathisp@gmail.com SP> If it is possible in theory to preserve brain function by replacing each neuron with a computer chip, that is if the brain is Turing emulable, then a particular brain program could run on an infinite number of general purpose computers.

Torbjörn Larsson> But this possibility is what I claimed earlier what you must establish. I can’t see that you have moved your argument.

Brains are made of matter which follows the well-understood laws of chemistry. Certainly it would be very difficult, like simulating the weather, but how is it possible that a neuron will do something that is uncomputable? Roger Penrose has had to speculate on an uncomputable theory of quantum gravity just to keep the brain special, but he is almost alone in his position.

Torbjörn Larsson> I think there is some confusion here, possibly on my part, since the possible improbability of deterministically copying a brain doesn’t preclude the stochastic probability of doing it.

Wow, what a complicated sentence that was!

stathisp@gmail.com

]]> By: Torbjörn Larsson http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/comment-page-1/#comment-25359 Torbjörn Larsson Mon, 26 Feb 2007 11:16:28 +0000 http://blogs.discovermagazine.com/cosmicvariance/2007/02/21/oos-and-bbs/#comment-25359 Stathis: Sorry for not answering timely. <blockquote> If it is possible in theory to preserve brain function by replacing each neuron with a computer chip, that is if the brain is Turing emulable, then a particular brain program could run on an infinite number of general purpose computers. </blockquote> But this possibility is what I claimed earlier what you must establish. I can't see that you have moved your argument. <blockquote> If the BB is to reproduce the function of a particular brain, it need only chance upon the configuration of one of these machines, actual or (infinitely larger set) possible. </blockquote> I think there is some confusion here, possibly on my part, since the possible improbability of deterministically copying a brain doesn't preclude the stochastic probability of doing it. Stathis:

Sorry for not answering timely.

If it is possible in theory to preserve brain function by replacing each neuron with a computer chip, that is if the brain is Turing emulable, then a particular brain program could run on an infinite number of general purpose computers.

But this possibility is what I claimed earlier what you must establish. I can’t see that you have moved your argument.

If the BB is to reproduce the function of a particular brain, it need only chance upon the configuration of one of these machines, actual or (infinitely larger set) possible.

I think there is some confusion here, possibly on my part, since the possible improbability of deterministically copying a brain doesn’t preclude the stochastic probability of doing it.

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