Re: a possible paradox
Federico: The paradox consists of the fact that the theory of multiverses tells us that there must be infinite observers who experiment other physical laws. There is not only the possibility of being wrong, it is the model itself which proves to be wrong. In fact it tells us that there are infinite places and times in this multiverse where, if any people observe the world around them in the same way we are doing hic et nunc, they necessarly find another model to describe the universe. So the outcome of the model is that it must be wrong in infinite places and times, and the paradox is that we have proved that it is wrong, but we have been able to draw this conclusion because we have considered the hypothesis of applying the physical system itself. But if it was wrong, the conclusions would be wrong, too. Ciao Federico, There is a debate about the consistency conditions that must be satisfied by (density matrices which represent) the knowledge that different people have about the ***same*** physical system. These knowledges (and density matrices) are, in general, different. So we must always ask (with John Bell) whose knowledge?. And then we must impose (Rudolf Peirls) the condition that density matrices must have a non-zero product (they must have at least one state in common). And that was the first level. Or, if you prefer, the first-order paradox. Now the question seems (to me) to be this one. What about the density matrix of the people A in the ***world*** A, representing some knowledge about the ***world*** B? What about the density matrix of the people B in the ***world*** B, representing some knowledge about the ***world*** A? The answer seems to be: more questions. Do these density matrices commute? I suppose: no. Do these density matrices share at least one state? I think the answer is, in general: no. And that was the second-order paradox. But the above was the case of people living in different ***worlds*** ***but*** believing in the same QM. Now you can imagine what is the problem when they do not even believe in the same QM (or QM interpretation!). And that, perhaps, is the third-order paradox. But maybe thay are not paradoxes. Informations are always subjective, more or less.
Fw: a possible paradox
Any reason this list does not have a reply-to set to the mailing list address? my message mistakenly sent to scerir I think two things are being confused. First, the laws of physics, second, the laws of probability. A gas particle follow physical rules (movement, bumping, thermal vibrations) and lots of gas particles together follow probability rules (low probability of people suffocating in rooms). The paradox Feredico is proposing is that in an infinite universe probability laws are local and not constant. Observers in different parts of the universe would come up with the same physical laws but different probability laws. Gas molecules will do their bumping the same way everywhere, but when put together in some pockets of inverted probability the molecules will have very high likelihood of ending up in room corners. 1. observers in these areas would make similar physical theories, different caos/statistics/probability theories 2. observers in many areas of the universe would not be able to evolve or survive since the system tends to extremes or does not favor stable physical behavior (evolution cannot happen) ... but there could be other kinds of evolution in these areas - just think about a gigantic bayesian system in which the right thoughts pop up because of different probability rules... superintelligence could be achieved very simply. So there is no real paradox, just the fact that probability rules are not constant in an infinite universe; I personally don't believe in things that are infinite though. mirai++
Re: a possible paradox
Any reason this list does not have a reply-to set to the mailing list address? Better push the reply to all? Btw, I wrote: Now the question seems (to me) to be this one. What about the density matrix of the people A in the ***world*** A, representing some knowledge about the ***world*** B? What about the density matrix of the people B in the ***world*** B, representing some knowledge about the ***world*** A? The answer seems to be: more questions. Do these density matrices commute? I suppose: no. Do these density matrices share at least ^ one state? I think the answer is, in general: no. ^ But now I'm not sure about the underlined words. (I'm not an expert in multiverses or MWI) s.
Re: a possible paradox
-- Federico Marulli [EMAIL PROTECTED] Hello everybody, I read all your messages and I would like to say something about them. I think that the concept of magic universes considered by Matt King and Hal Finney and the demonstration that we are not in one of them is improper. If these magic universes realy existed, I believe that we would have no way to say if we are in one of them. My reasoning is that we think that our universe is the most probable one only because we are in it. But other infinite observers living in other regions of this multiverse would think in a completly different way believing to be themself privileged observers. How can we demostrate to be privileged? All our physics may have been found by chance. Our universe could be the most improbable one and constistency between the physics of the large and the small could have found by chance too. For our opinion there is a very small probability for it, but for the infinite other observers perhaps not. I am also not agree with Mirai saying I think two things are being confused. First, the laws of physics, second, the laws of probability. A gas particle follow physical rules (movement, bumping, thermal vibrations) and lots of gas particles together follow probability rules (low probability of people suffocating in rooms). The problem is that all the laws of physics have been found observing the world around us in an experimental way. But all the outcomes of an experiment are probabilistc and we know the low of physics only with a certain error. So the paradox in the laws of probability is a paradox in laws of physics too. The whole physics is probabilistic. Finally I would like to anser to scerir But the above was the case of people living in different ***worlds*** ***but*** believing in the same QM. Now you can imagine what is the problem when they do not even believe in the same QM (or QM interpretation!). And that, perhaps, is the third-order paradox. But maybe thay are not paradoxes. Informations are always subjective, more or less. I'm agree that informations are always subjective, but a physical or matematical model should not be too. And perhaps the paradox I propose is a four-order one. The problem in fact is that all the conclusions we could think are consequence of the hypotesis of applying the physical and matematical system. But if they were wrong, the conclusions would be wrong, too. So the simple fact to consider that there could be other observers not believing in the same QM could be a nonsense. Federico
Re: a possible paradox
Hi Hal, I agree with everything you wrote about duplication...but I have to take issue with your last point. Hal Finney wrote: Another interesting result of this paper concerned daughter universes. In some models, it may be possible to trigger the formation of new inflating regions which would bud off from our own space time and produce their own infinite-sized level 2 universes. The authors of this paper had proposed in an earlier one that this could be a mechanism for civilizations to survive heat death, that they could create daughter universes and somehow send information into them which could be taken up and incorporated by civilizations evolving in the daughter universes. However, in the context of the multiverse, this won't really work, because any finite number of messages are insignificant in the context of an infinitely-duplicated multiverse. Only a finite number of regions can receive the messages, compared to an infinite number of regions that either don't receive them, or receive spontaneously-generated fake messages (like our discussion earlier today of magical universes). Therefore the messages can have only an infinitesimal impact on the evolution of the daughter universes and cannot be considered a meaningful form of survival. I think that the survival would be meaningful for the civilisation doing the broadcasting so long as at least one daughter universe is able to replicate the civilisation, just as I have meaningfully survived so long as future versions of me exist somewhere in the multiverse, even if I only survive in an infinitessimally small fraction of the universes (Quantum Immortality). Matt. When God plays dice with the Universe, He throws every number at once...
Re: a possible paradox
Hello Stathis and James, In answer to the first question, does the multiverse inlude perfect duplications of entire universes, the answer is yes with a but. Any particular universe in it can be sliced up in any number of ways, just as 1 = (1/n + 1/n + 1/n. n times) for any value of n. This gives rise to a picture of a very large number of universes differentiating from each other as time moves forward, as opposed to the more conventional picture of a single universe splitting as time moves forward. Both pictures seem to be mathematically valid and mutually compatible, IMHO. The fact that at a particular instant any given universe has multiple possible futures means that any given universe can be considered as a sum of however many identical copies of that universe you like. In answer to the second question, in addition to these perfect duplications, there are duplications that differ only by the state of a single photon somewhere in a galaxy on the other side of the universe (i.e. arbitrarily close), as well as 'duplications' that share nothing in common with our universe save the laws of physics, and everything in between. In the plenitude theories of Max Tegmark and others, the requirement that other universes share the same laws of physics and the same big bang is relaxed. Hope this helps, Matt. Stathis Papaioannou wrote: Let me add a postscript to this quicky: does the multiverse include perfect duplications, or only arbitrarily close to perfect - and does it make a difference? Stathis From: James N Rose [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Re: a possible paradox Date: Wed, 29 Oct 2003 15:52:30 -0800 quicky: does the multiverses version of existence include perfect duplications - included redundencies - of universes? James _ Hot chart ringtones and polyphonics. Go to http://ninemsn.com.au/mobilemania/default.asp -- When God plays dice with the Universe, He throws every number at once...
Re: a possible paradox
Federico: I'm agree that informations are always subjective, but a physical or matematical model should not be too. And perhaps the paradox I propose is a four-order one. The problem in fact is that all the conclusions we could think are consequence of the hypotesis of applying the physical and matematical system. But if they were wrong, the conclusions would be wrong, too. Principles of World Theory say, more or less, that: - a proposition (whatever) is *necessary* iff it is true in all worlds; - a proposition (whatever) is *possible* iff there is some world in which it is true; - there is only one *actual* world; - there are propositions which are true at the *actual* world; - there are propositions which are not true at the *actual* world, but they are true at some *non-actual* *possible* world. It is not much. But, in any case, we must start from these points :-)
[Fwd: a possible paradox]
Joao Leao wrote: Your Principles are correct but the wording is not: you should change all your use of *possible* to 'contingent' and qualify as 'possible' instead all the invocations of 'world' not qualified with *actual*. This because possible/actual is a distinction that applies to worlds while necessary/contingent applies to propositions... -Joao scerir wrote: Federico: I'm agree that informations are always subjective, but a physical or matematical model should not be too. And perhaps the paradox I propose is a four-order one. The problem in fact is that all the conclusions we could think are consequence of the hypotesis of applying the physical and matematical system. But if they were wrong, the conclusions would be wrong, too. Principles of World Theory say, more or less, that: - a proposition (whatever) is *necessary* iff it is true in all worlds; - a proposition (whatever) is *possible* iff there is some world in which it is true; - there is only one *actual* world; - there are propositions which are true at the *actual* world; - there are propositions which are not true at the *actual* world, but they are true at some *non-actual* *possible* world. It is not much. But, in any case, we must start from these points :-) -- Joao Pedro Leao ::: [EMAIL PROTECTED] Harvard-Smithsonian Center for Astrophysics 1815 Massachussetts Av. , Cambridge MA 02140 Work Phone: (617)-496-7990 extension 124 VoIP Phone: (617)=384-6679 Cell-Phone: (617)-817-1800 -- All generalizations are abusive (specially this one!) --- -- Joao Pedro Leao ::: [EMAIL PROTECTED] Harvard-Smithsonian Center for Astrophysics 1815 Massachussetts Av. , Cambridge MA 02140 Work Phone: (617)-496-7990 extension 124 VoIP Phone: (617)=384-6679 Cell-Phone: (617)-817-1800 -- All generalizations are abusive (specially this one!) ---
Re: a possible paradox
Thanks, Matt, yes it helps. It helps me see that the math becomes problematic under the interpretations. Arbitrary constraints tint and skew what comes out. James Matt King wrote: Hello Stathis and James, In answer to the first question, does the multiverse inlude perfect duplications of entire universes, the answer is yes with a but. Any particular universe in it can be sliced up in any number of ways, just as 1 = (1/n + 1/n + 1/n. n times) for any value of n. This gives rise to a picture of a very large number of universes differentiating from each other as time moves forward, as opposed to the more conventional picture of a single universe splitting as time moves forward. Both pictures seem to be mathematically valid and mutually compatible, IMHO. The fact that at a particular instant any given universe has multiple possible futures means that any given universe can be considered as a sum of however many identical copies of that universe you like. [snip] In the plenitude theories of Max Tegmark and others, the requirement that other universes share the same laws of physics and the same big bang is relaxed. Hope this helps, Matt.
Re: a possible paradox
Dear Federico, In a mature and open 'exploring community', especially where people of different language backgrounds are concerned about coming together, the responsibility for extracting meaning and ideas falls as much on the readers as the writers. Syntax and grammer 'perfection' are secondary to the ideas and meanings shared, which you accomplish very very well. James Federico Marulli wrote: I have just read my last message and I have realized there were a lot of mistakes dealing with the English language. I'm sorry for that, I hope to improve my writing skills as soon as possible. Federico
Re: a possible paradox
get fucked
Re: a possible paradox
get fucked Well, based upon the vast vocabulary as evidenced by this incisive argument by the poster, obviously a man of the vast intellect and insight of a George Bush! Impressive indeed! Cheers
Re: a possible paradox
Tegmark's multiverse theory doesn't make it appropriate to initiate -- or multiply -- the gratuitous. get fucked Well, based upon the vast vocabulary as evidenced by this incisive argument by the poster, obviously a man of the vast intellect and insight of a George Bush! Impressive indeed! Cheers
Re: a possible paradox
How do I unsubscribe from this list - there appears to be no DIGEST version and you should have an unsubscribe with every email. -- Original Message -- From: James N Rose [EMAIL PROTECTED] Date: Thu, 30 Oct 2003 09:27:25 -0800 Thanks, Matt, yes it helps. It helps me see that the math becomes problematic under the interpretations. Arbitrary constraints tint and skew what comes out. James Matt King wrote: Hello Stathis and James, In answer to the first question, does the multiverse inlude perfect duplications of entire universes, the answer is yes with a but. Any particular universe in it can be sliced up in any number of ways, just as 1 = (1/n + 1/n + 1/n. n times) for any value of n. This gives rise to a picture of a very large number of universes differentiating from each other as time moves forward, as opposed to the more conventional picture of a single universe splitting as time moves forward. Both pictures seem to be mathematically valid and mutually compatible, IMHO. The fact that at a particular instant any given universe has multiple possible futures means that any given universe can be considered as a sum of however many identical copies of that universe you like. [snip] In the plenitude theories of Max Tegmark and others, the requirement that other universes share the same laws of physics and the same big bang is relaxed. Hope this helps, Matt.
Re: a possible paradox
lighten up benny - Original Message - From: Benjamin Udell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Thursday, October 30, 2003 11:57 AM Subject: Re: a possible paradox Tegmark's multiverse theory doesn't make it appropriate to initiate -- or multiply -- the gratuitous. get fucked Well, based upon the vast vocabulary as evidenced by this incisive argument by the poster, obviously a man of the vast intellect and insight of a George Bush! Impressive indeed! Cheers
RE: a possible paradox
Everytime this thread is responded to with the F word our IT department gets notified and, in turn, notifies me about a blip on the content filter. Its a pain in my ass, so please drop the word if responding. Thanks.
Re: a possible paradox
Actually I wasn't thinking about physically impossible things happening very rarely (QM) but only about regular physics vs probability of things happening. If you consider quantum mechanics you are right in an infinite universe there could be areas in which physics just happens to work very differently, people there would formulate very different physical laws (if people could evolve, or spontaneously appear). So if the universe is infinite, it doesn't make much sense to talk about laws of physics. Still there need to be some fundamental rules that never change, for example the fact that something exists. You can't have areas of the universe in which the universe itself does note exist (I think). Frankly I don't believe the universe is infinite, occam's razor says it's just very big. Last month there was a report about someone finding a pattern in galaxies that would suggest the universe is much smaller than we thought but light wraps around making it appear infinite... the theory was discarded very soon after more experiments were carried out, but it reminded me of that star trek episode.. state the nature of the universe - the universe is a hollow sphere 12 km in diameter ... or something. Infinity is just our perception of things very big... something that originates from nothingness and expands has very little chances of becoming infinite in finite time. mirai++ I think two things are being confused. First, the laws of physics, second, the laws of probability. A gas particle follow physical rules (movement, bumping, thermal vibrations) and lots of gas particles together follow probability rules (low probability of people suffocating in rooms). The problem is that all the laws of physics have been found observing the world around us in an experimental way. But all the outcomes of an experiment are probabilistc and we know the low of physics only with a certain error. So the paradox in the laws of probability is a paradox in laws of physics too. The whole physics is probabilistic.
Re: a possible paradox
To repeat Tegmark's rhetorical question (and he's probably not the originator), If the multiverse is finite, what's outside it's edge? Norman - Original Message - From: Mirai Shounen [EMAIL PROTECTED] To: Federico Marulli [EMAIL PROTECTED]; [EMAIL PROTECTED] Sent: Thursday, October 30, 2003 1:14 PM Subject: Re: a possible paradox Actually I wasn't thinking about physically impossible things happening very rarely (QM) but only about regular physics vs probability of things happening. If you consider quantum mechanics you are right in an infinite universe there could be areas in which physics just happens to work very differently, people there would formulate very different physical laws (if people could evolve, or spontaneously appear). So if the universe is infinite, it doesn't make much sense to talk about laws of physics. Still there need to be some fundamental rules that never change, for example the fact that something exists. You can't have areas of the universe in which the universe itself does note exist (I think). Frankly I don't believe the universe is infinite, occam's razor says it's just very big. Last month there was a report about someone finding a pattern in galaxies that would suggest the universe is much smaller than we thought but light wraps around making it appear infinite... the theory was discarded very soon after more experiments were carried out, but it reminded me of that star trek episode.. state the nature of the universe - the universe is a hollow sphere 12 km in diameter ... or something. Infinity is just our perception of things very big... something that originates from nothingness and expands has very little chances of becoming infinite in finite time. mirai++ I think two things are being confused. First, the laws of physics, second, the laws of probability. A gas particle follow physical rules (movement, bumping, thermal vibrations) and lots of gas particles together follow probability rules (low probability of people suffocating in rooms). The problem is that all the laws of physics have been found observing the world around us in an experimental way. But all the outcomes of an experiment are probabilistc and we know the low of physics only with a certain error. So the paradox in the laws of probability is a paradox in laws of physics too. The whole physics is probabilistic.
Re: a possible paradox
I've not posted to this group previously, but I can't resist this one ;^) Hal Finney wrote: Matt King writes: I should point out that there does remain a vanishingly small possibility that we could be in one of the extremely 'magical' universes where both macroscopic and microscopic laws of physics are skewed in a mutually consistent way, however given the tiny probability of this being the case I think it is quite safe to ignore it. That seems rather extreme, because the probablity that we are in a regular magical universe is already vanishingly small and we would truly be safe in ignoring it. Even the probability of observing a single large scale violation of the laws of probability is vanishingly small. (Magical universes suffer from repeated large-scale According to *our* laws of probability, that is. But how can you make recourse to our laws of probability if there are infinitely many universes which have different laws? Isn't Frederico's original proposition based on assuming infinite variability and duplication of probability theory amongst all level 1 universes? So I would think that taking the assumption onboard means you cannot argue we are 'probably' in one of the more common universes... since 'probably' changes from universe to universe. Correct me if I'm wrong! Jules
Re: a possible paradox
Dear Mirai and Federico and Friends, Could we cover the White Rabbit and Harry Potter universes by considering that for a pair of systems to interact their individual histories must not contradict each other? This, I think, would also cover interactions between the MWI branches. Kindest regards, Stephen - Original Message - From: Mirai Shounen [EMAIL PROTECTED] To: Federico Marulli [EMAIL PROTECTED]; [EMAIL PROTECTED] Sent: Thursday, October 30, 2003 4:14 PM Subject: Re: a possible paradox Actually I wasn't thinking about physically impossible things happening very rarely (QM) but only about regular physics vs probability of things happening. If you consider quantum mechanics you are right in an infinite universe there could be areas in which physics just happens to work very differently, people there would formulate very different physical laws (if people could evolve, or spontaneously appear). So if the universe is infinite, it doesn't make much sense to talk about laws of physics. Still there need to be some fundamental rules that never change, for example the fact that something exists. You can't have areas of the universe in which the universe itself does note exist (I think). Frankly I don't believe the universe is infinite, occam's razor says it's just very big. Last month there was a report about someone finding a pattern in galaxies that would suggest the universe is much smaller than we thought but light wraps around making it appear infinite... the theory was discarded very soon after more experiments were carried out, but it reminded me of that star trek episode.. state the nature of the universe - the universe is a hollow sphere 12 km in diameter ... or something. Infinity is just our perception of things very big... something that originates from nothingness and expands has very little chances of becoming infinite in finite time. mirai++ I think two things are being confused. First, the laws of physics, second, the laws of probability. A gas particle follow physical rules (movement, bumping, thermal vibrations) and lots of gas particles together follow probability rules (low probability of people suffocating in rooms). The problem is that all the laws of physics have been found observing the world around us in an experimental way. But all the outcomes of an experiment are probabilistc and we know the low of physics only with a certain error. So the paradox in the laws of probability is a paradox in laws of physics too. The whole physics is probabilistic.
Quantum accident survivor
Another quickie: Assume I survive a car/plane crash which we assume could have many different quantum outcomes including me (dead || alive) Since I was the same person (entire life history) up until the crash/quantum 'branch' - then can't I assume that since there was at least one outcome where I survived, that TO ME I will always survive other such life/death branches? Furthermore if I witness a crash where someone dies can I assume that the victim will survive in their own world so far as at least one quantum branch of survivability seems possible? David Kwinter
Re: Quantum accident survivor
Hello David, David Kwinter wrote: Another quickie: Assume I survive a car/plane crash which we assume could have many different quantum outcomes including me (dead || alive) Since I was the same person (entire life history) up until the crash/quantum 'branch' - then can't I assume that since there was at least one outcome where I survived, that TO ME I will always survive other such life/death branches? Furthermore if I witness a crash where someone dies can I assume that the victim will survive in their own world so far as at least one quantum branch of survivability seems possible? Yes, this is Quantum Immortality in a nutshell. If the MWI is correct, it is impossible to die from a subjective point of view. Hooray! Matt. When God plays dice with the Universe, He throws every number at once...
Re: Quantum accident survivor
David Kwinter, [EMAIL PROTECTED], writes: Assume I survive a car/plane crash which we assume could have many different quantum outcomes including me (dead || alive) Since I was the same person (entire life history) up until the crash/quantum 'branch' - then can't I assume that since there was at least one outcome where I survived, that TO ME I will always survive other such life/death branches? Furthermore if I witness a crash where someone dies can I assume that the victim will survive in their own world so far as at least one quantum branch of survivability seems possible? You can assume anything you like! Seriously, we have had extensive and occasionally acrimonious debates on this topic in the past, without much success or resolution. I think that we have no good foundation for establishing the truth or falsehood of any theory of identity in absolute terms. Instead, these issues must be considered matters of taste. You can indeed choose to believe that as long as any version of yourself continues in any universe, then you will consider yourself to still be alive. You could also choose the contrary, that if the total measure (ie. probability) of your survival is extremely small, that you are dead. Hal Finney
Re: Quantum accident survivor
Hi there, Hal, one nitpick about your comments: In the case of Quantum Immortality, I don't think it's a matter of taste, or interpretation. It is a theory that every one of us can and ultimately will test. Granted, we will only be aware of a positive result, but, nevertheless... cheers, Frank From: Hal Finney [EMAIL PROTECTED] You can assume anything you like! Seriously, we have had extensive and occasionally acrimonious debates on this topic in the past, without much success or resolution. I think that we have no good foundation for establishing the truth or falsehood of any theory of identity in absolute terms. Instead, these issues must be considered matters of taste. You can indeed choose to believe that as long as any version of yourself continues in any universe, then you will consider yourself to still be alive. You could also choose the contrary, that if the total measure (ie. probability) of your survival is extremely small, that you are dead. Hal Finney
Quantum accident survivor
It would seem that there are a finite number of ways to survive (or die in) any given car accident. It that's the case, the number of many world branches would be limited by this value. Taken longitudinally, it would seem that the architecture of the world lines of these and similar events would limit the number of worlds associated with the individual. That is, after such a life-threatening event, the number of multiple copies of the individual become limited. R. Miller
Re: Quantum accident survivor
On Thursday, October 30, 2003, at 08:11 PM, Benjamin Udell wrote: Assume I survive a car/plane crash which we assume could have many different quantum outcomes including me (dead || alive) Since I was the same person (entire life history) up until the crash/quantum 'branch' - then can't I assume that since there was at least one outcome where I survived, that TO ME I will always survive other such life/death branches? Furthermore if I witness a crash where someone dies can I assume that the victim will survive in their own world so far as at least one quantum branch of survivability seems possible? Yes, this is Quantum Immortality in a nutshell. If the MWI is correct, it is impossible to die from a subjective point of view. Hooray! Survive as what, though? And in what condition? I know from personal experience that one does not always experience oneself in that world-branch in which one is in tip-top shape. Reminds me of the ancient Greek myth of the goddess whose mortal lover was granted immortality at her request by Zeus, but not eternal youth, because it didn't occur to the goddess to ask Zeus to grant her lover that too. So the lover never died, but grew ever older, more wrinkled bent, till he became a grasshopper. Hmm sounds like quantum immorality leaves us all old, crippled and miraculously dodging (typical) eventualities. The version of quantum self-preservation I find reasonable is where accidents have an estimated survivability of ~50%. ie, If you get killed by a comet, it's very safe to say that minor quantum events could've moved it a couple feet away. Being born in the 10th century for example and living forever could not have been possible via quantum branches, right? Technological evolution takes time.. Are there any really good arguments out there for QI? (not to bother you - I will research this on my own) Thanks David Kwinter
Re: multiverse paradox of a number of posts back
Someone wrote: The paradox consists of the fact that the theory of multiverses tells us that there must be infinite observers who experiment other physical laws. There is not only the possibility of being wrong, it is the model itself which proves to be wrong. In fact it tells us that there are infinite places and times in this multiverse where, if any people observe the world around them in the same way we are doing hic et nunc, they necessarly find another model to describe the universe. So the outcome of the model is that it must be wrong in infinite places and times, and the paradox is that we have proved that it is wrong, but we have been able to draw this conclusion because we have considered the hypothesis of applying the physical system itself. But if it was wrong, the conclusions would be wrong, too. Apologies to long-time list members for re-iterating like a broken record... I think when people speculate about other universes in the multiverse, they continually fail to grasp the likely extremely constrained nature of OBSERVABLE universes. An observable universe MUST be structured/defined so as to be capable of evolving self-aware substructures (SAS's) such as ourselves, in order for it to be in-principle observable. I posit that these constraints are EXTREMELY ONEROUS. No, this is not some naive anthropocentrism. I'm working from intuitions about emergent systems theory, and notions of the highly constrained energy regimes in which self-organization of systems can occur (At least, self-organization of systems that have properties likely to lead to coherent observer-systems.) IT COULD BE that all alternative people MUST be seeing a universe very similar to ours, or indeed possibly EXACTLY ours, simply because otherwise their self-organization would NECESSARILY break down in their universe, and they couldn't observe. In other words, it COULD be that there is only one OBSERVABLE POSSIBLE world. Now that's an extreme, I admit, but I think it's closer to the truth than imagining infinite numbers of really weird, unimaginable observers in really weird, unimaginable alternative universes. The main point is that the constraints required to produce EMERGENT SYSTEMS that can be classified as what we think of as OBSERVERS may be, again EXTREMELY onerous, extremely possibility-constraining constraints. There may be, in the imagination, other weirdo observers coming up with a weirdo model of the universe, but maybe some inconsistency in the notion of their existence (as complex, stable systems in a complex yet stable habitat) in their world means that they simply CAN'T exist. Eric
