Re: a possible paradox
I think that those who defends the ASSA, are unconsciously working with the Aristotle/Leibniz S5 modal logic where worlds/states/observer-moments are all accessible from each other (or, it is equivalent, they are no accessible relation playing any role in the semantics of the box). The RSSA corresponds then to Kripkean/Lewisian modal logics. With comp we get instead the couple of Solovay-Godel-Lob (Kripkean) logics (G and G*), which makes the "everything" idea much more fertile. In particular G and G* makes easy the translation of the UD Argument into Arithmetic, and it gives an intuitionistic (brouwerian) logic for the first person, and a quantum logic for the first plural sharable (self) observation. Bruno At 13:24 04/11/03 +0100, "scerir" <[EMAIL PROTECTED]> wrote: [me] > >Principles of World Theory say, more or less, that: [...] [Bruno] > Very nice. Except perhaps that it is the principle of the > Old World Theory, implicit in Aristotle > and Leibniz, where all the worlds are accessible from each other. > It is formalised by the modal logic S5. [...] I'll do my homework :-) I remember that, about 30 years ago, I was interested in modal-QM, intensional-QM, self-referential-QM. I realized that perhaps intensional-QM now is called contextual-QM and nobody (?) in the mean time studied self-referential issues of QM. Anyway I forgot all the technical means now, and I must do my homework :-) Regards, serafino
Re: a possible paradox
[me] > >Principles of World Theory say, more or less, that: [...] [Bruno] > Very nice. Except perhaps that it is the principle of the > Old World Theory, implicit in Aristotle > and Leibniz, where all the worlds are accessible from each other. > It is formalised by the modal logic S5. [...] I'll do my homework :-) I remember that, about 30 years ago, I was interested in modal-QM, intensional-QM, self-referential-QM. I realized that perhaps intensional-QM now is called contextual-QM and nobody (?) in the mean time studied self-referential issues of QM. Anyway I forgot all the technical means now, and I must do my homework :-) Regards, serafino
Re: a possible paradox
Brent Meeker wrote: Even the probability of observing a single large scale violation of the laws of probability is vanishingly small. 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? > What are the laws of probability that might differ? That less probable things happen more often than more probable one? Heh. You are trying to define probability in terms of itself. I imagine a corner of existence where (as a previous poster described) a die returns 6 every time. My whole point is: our stubborn insistence that 1, 2, 3, 4, 5 *or* 6 are just as probable as each other would be laughed at in such a corner of existence. If we happened to live in this other corner of existence, our statistical models would have developed along very different lines. And isn't it a little naive to assume that us humans of Earth have the only 'correct' statistical model, just because it happens to reconcile with the results of our experiments? I guess I am saying that math is not devoid of our physical context... how can it be? That it has empirical elements to it. Consider the case for us: For the sake of the argument, imagine that I used math to produce some absurd result, then the mathematical reasoning must be flawed. But presume I used only accepted rules of inference. Then the rules of inference must be inconsistent. Reductio ad absurdum. But to apply this argument, we must determine that the result is absurd. There's the rub. Often an argument is absurd 'by investigation' or 'by inspection'. Sounds like empirical evidence to me! So if I used our statistical laws to derive a 'proof' in this other universe whereby it was just as likely to roll a 1 as it was to roll a 6, wouldn't the inhabitants of this universe use investigation and r.a.a to disprove my inference laws and their conclusion? And who would be 'correct' do you think? Jules
RE: a possible paradox
Hi, I´m new here. Please accept this source of extra noise in your mailbox in the hope to be useful Federico Marulli wrote: > So we can try to reason upon some examples which has a meaning from a > physical point of view. For instance, we can think about the second > principle of thermodynamics, according to which the entropy of a closed > system necessarly has to increase. That means that, for instance, a gas > put into a container of volume V will tend to spread by occupying all the > available volume. This way we get the most possible disorder and the state > is the most probable. Anyway the state in which all the gas is firmly in a > v < V volume is not forbidden by thermodynamics; it is just a rather > improbable state. But this event, having some chances to take place, has > to happen in infinite places and times in our multiverse. So there will be > infinite Hubble spheres in which everything happens exactly as in our own > sphere, but in which any time you put a gas into a container, it will > never occupy the whole volume. At the same time, there will be infinite > spheres in which some day the gas will occupy all the volume and some > others not. And so on. The estrange behaviours like this can be prohibited by physical laws we don't already know or new consequences discovered from already known laws. In particular the case above, I think we may have a law that has consequences that prohibits such entropic behaviour: Statistical mechanics. As the gas is made by particles which moves in all directions it is easy to see that in the absence of any obstacle, the particles would go straight ahead in all directions to fill all the available space with no exceptions. I´m almost sure that it is impossible to avoid the expansion by means of "well designed" particle collisions. A serious study of this question may be a good statistical mechanic work to be done. I know that this argument is rather simple but I think that no serious work has been done to discard it. My guess is that simply we do not know the reality well enough to be sure that these magical worlds are possible. I confess that, it is more difficult to argue against other probabilistic events mentioned by Federico. May be that each one of the mentioned examples are clearly different and requires a separate study
Re: a possible paradox
These models with topological non-local features may not actually have "outsides" by the same token that the Mobius band only has one side, get it? Max Tegmark is a nice kid but he does not seem to deal very well with his own finitude ! I am sure he is not the only one... -Joao Leao Norman Samish wrote: > 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. > > > > > -- Joao Pedro Leao ::: [EMAIL PROTECTED] Harvard-Smithsonian Center for Astrophysics 1815 Massachussetts Av. , Cambridge MA 02140 Work Phone: (617)-496-7990 extension 124 Cell-Phone: (617)-817-1800 -- "All generalizations are abusive (specially this one!)" ---
Re: a possible paradox
At 17:03 30/10/03 +0100, "scerir" <[EMAIL PROTECTED]> wrote: 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 :-) Very nice. Except perhaps that it is the principle of the Old World Theory, implicit in Aristotle and Leibniz, where all the worlds are accessible from each other. It is formalised by the modal logic S5. Abbreviating "necessary p" by box p, or []p, and "possible p" by <>p (which itself can be seen as an abbreviation of "not box not p", i.e. -[] - p), its main axiom are []p -> p, []p->[][]p, and <>p -> []<>p. Search S5, in the archive, I have given the precise axioms and inference rules, at some time. Kripke has relativized such sort of modal logic by saying that []p is true in a world A if p is true in all world accessible from A. Then for each choice of an accessibility relation, you get a different modal logic. And modal logic is the best tool for being precise on the invariant truth (like laws) in a multiverse, or in contextual frame, etc. Also, modal logics can be used to simulate in the classical settings, non classical logics, like intutionistic logic, quantum logic. I agree with we should, well perhaps not start from that, but invoking them when we disagree about the validity of an argument in *apparently* fuzzy context. I work mainly with the modal logic G and G* (see the archive). This can help for giving axiomatic notion of self-identities. Bruno
RE: a possible paradox
Surely you can't be serious! Are you saying that every letter of every word of every email in your institution is scrutinised by your IT department? I know this has nothing to do with the business of the everything list, but good grief, this kind of surveillance Hitler and Stalin could only dream about! Every letter of every word of every email... say it slowly to yourself three times... I'll be afraid to go to bed tonight thinking about it! -Original Message- From: Mike Connelly [mailto:[EMAIL PROTECTED] Sent: Friday, 31 October 2003 8:13 AM To: CMR; Benjamin Udell Cc: [EMAIL PROTECTED] Subject: 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. _ Hot chart ringtones and polyphonics. Go to http://ninemsn.com.au/mobilemania/default.asp
Re: a possible paradox
Matt King wrote: > ...However, the laws of probability themselves are not physical but > mathematical in origin. Even in a 'magical' universe, you would still > have the same basic laws of probability (Gaussian distributions and the > like) as this is just math, and math is truly universal. For > example, if you make the assumption that a die is evenly weighted, you > will get the same statistical models about dice throwing whichever > universe you happen to be in. What would be different in a 'magical' > universe is that these laws of probability would not seem to apply to > a particular physical system - or much more rarely - to any particular > physical system, so you could be in a 'magical' universe where > although your statistical model predicts differently, you always throw > double six, for instance. > >The fact that physical systems in our universe do obey probabilistic > laws like thermodynamics is therefore extremely good evidence that we > are not in such a 'magical' universe. Tegmark and other people think that mathematical existence = physical existence. But we are saying that there are infinite observers for whom the physical evidence always (or almost) contradict the mathematical law of probability. What could these other observers think? Could they think that, by coincidence, the mathematical existence is always (or almost) in contraddiction with physical existence? And, if so, how could they study the universe? Maybe through other "types" of mathematics? May "our" mathematics be not so fondamental? May we have "our" mathematics only because we live in this part of the multiverse? Or is math truly universal and consequently the assumption "mathematical existence = physical existence" is not so truly universal? James N Rose wrote: > 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. Thanks a lot, You are very kind. SOMEONE wrote: > 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. Well, perhaps I have to apologize to long-time list members, too (...this is the usual fashion in this mailing list, isn't it? Anyway, I would'n want to sound like a crawler...). Then I would like to underline some basic considerations. A universe where the only weird thing is the fact to obtain number 6 any time you throw a die doesn't violate any "extremely possibility-constraining constraints". A universe where, by chance, the Lutezio element always occupy 99.5679459 percent of the volume available only when it is in a Astato box, doesn't transgress the constraints of the existence of self-organization. And so on. There could be an infinite of other examples (...and beyond!). Could there be only one "OBSERVABLE POSSIBLE" world? ...almost surely the multiverse teory doesn't tell us that...
Re: a possible paradox
Hi Julian,
Julian Suggate wrote:
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!
...However, the laws of probability themselves are not physical but
mathematical in origin. Even in a 'magical' universe, you would still
have the same basic laws of probability (Gaussian distributions and the
like) as this is just math, and math is truly universal. For example,
if you make the assumption that a die is evenly weighted, you will get
the same statistical models about dice throwing whichever universe you
happen to be in. What would be different in a 'magical' universe is
that these laws of probability would not seem to apply to a particular
physical system - or much more rarely - to any particular physical
system, so you could be in a 'magical' universe where although your
statistical model predicts differently, you always throw double six, for
instance.
The fact that physical systems in our universe do obey probabilistic
laws like thermodynamics is therefore extremely good evidence that we
are not in such a 'magical' universe.
Hope this helps,
Matt.
When God plays dice with the Universe, He throws every number at once...
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. > > > >
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
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
The idea that the Universe has an funky topology with periodic boundaries of distant regions warped into each other like a Klein bottle or such, has been around for a while. The main speculator along these lines has been Jean-Pierre Luminet but most of the bru-ha-ha around the recent Nature article http://arXiv.org/abs/astro-ph/0310253 was centered on on J. Weeks (maybe because he is a McArthur Fellow and the only author based in the US). Their speculation apparently does not pan out with the current WMAP data as they claim but I don't think it has been put to rest quite yet. There will be better probes in the near future and CMB anisotropies detail are only coming on line slowly. Theories of the warpped universe are the spacial counterparts of the cyclic (in time) universe scenario of Turok and Steinhardt that someone mentioned recently in this list. This solves all of the problems addressed by inflation in a consistent way without recourse to dilatonics, false vacua and such lore. My guess is that these two phenomenological pictures will evolve sometime into one finite universe theory with nontrivial space-time topology... which will vindicate Nitzsche! And than again, I may be wrong. -Joao Leao Mirai Shounen wrote: > 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. > > -- Joao Pedro Leao ::: [EMAIL PROTECTED] Harvard-Smithsonian Center for Astrophysics 1815 Massachussetts Av. , Cambridge MA 02140 Work Phone: (617)-496-7990 extension 124 Cell-Phone: (617)-817-1800 -- "All generalizations are abusive (specially this one!)" ---
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
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
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
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
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
> 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
get fucked
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
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
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 :-)
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
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
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
-- 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
> 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: ^ 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: > 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.
Re: a possible paradox
Stathis Papaioannou, <[EMAIL PROTECTED]>, writes: > 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? It depends on what you mean by the multiverse, and on what the laws of physics are locally. I just happened to be reading a paper linked from Max Tegmark's page which answers the question in the affirmative for the level 1 and level 2 multiverse(s). The paper is "Many worlds in one", by Garriga and Vilenkin, http://arxiv.org/abs/gr-qc/0102010. Tegmark's level 1 multiverse is our universe when it is taken to be infinite in size. There should be duplicates of each finite sized region. The level 2 multiverse is the larger ensemble predicted by inflation theory. It contains an infinite number of level 1 multiverses, each infinite in size. The Garriga/Vilenkin paper explains more clearly than anything I had previously read how we can fit an infinite number of infinite sized level 1 universes into the level 2 universe. The answer is that inflation occurs exponentially fast and lasts forever. In relativity, time and space are somewhat interchangeable. From the level 2 perspective, new space is constantly (and rapidly) being added to each level 1 universe. Because this goes on forever, the "eventual" size of each level 1 region is infinitely large. But because of the interchangeability, when we look at it from the "inside view" of each level 1 universe, it can be considered to have been born infinitely large. The other main goal of this paper is to argue that the observable finite-sized regions of the universe do have exact duplicates elsewhere in the level 1 and level 2 ensemble. The duplicates are not merely approximate, but rather they are exact. This is based on quantum theory only allowing a finite amount of information to be present in a region (the Bekenstein bound). Therefore our whole observable universe bubble has only a finite number of bits in it, and so there should be an infinite number of other bubbles with exactly the same pattern of bits, and these are exact duplicates. 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. Hal Finney
Re: a possible paradox
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
Re: a possible paradox
Hi Hal,
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 violations.)
Going beyond that and asking for consistency between the physics of the
large and the small is really gilding the lily. I don't see what would
motivate you to draw the line there.
Oh I quite agree that it is overwhelmingly likely that we're not in a
'magical' universe anyway. My point concerned trying to *demonstrate*
that we're not, which is easily done if you assume 'magical' universes
with consistent macroscopic and microscopic physics are even rarer than
'magical' universes in general.
Matt.
--
When God plays dice with the Universe, He throws every number at once...
Re: a possible paradox
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 violations.)
Going beyond that and asking for consistency between the physics of the
large and the small is really gilding the lily. I don't see what would
motivate you to draw the line there.
Hal Finney
Re: a possible paradox
quicky: does the multiverses version of existence include perfect duplications - included redundencies - of universes? James
Re: a possible paradox
Hello Frederico, I've recently been taking part in a discussion on very similar lines on the Fabric of Reality mailing list (yahoo groups). Federico Marulli wrote: My reasoning is rather simple. Dealing with an infinite level 1 multiuniverse, if an event, even an improbable one, doesn't violate any pshysical laws, it necessarly has to happen infinite times and in infinite different points of the space. So we can try to reason upon some examples which has a meaning from a physical point of view. For instance, we can think about the second principle of thermodynamics, according to which the entropy of a closed system necessarly has to increase. That means that, for instance, a gas put into a container of volume V will tend to spread by occupying all the available volume. This way we get the most possible disorder and the state is the most probable. Anyway the state in which all the gas is firmly in a v < V volume is not forbidden by thermodynamics; it is just a rather improbable state. But this event, having some chances to take place, has to happen in infinite places and times in our multiverse. So there will be infinite Hubble spheres in which everything happens exactly as in our own sphere, but in which any time you put a gas into a container, it will never occupy the whole volume. At the same time, there will be infinite spheres in which some day the gas will occupy all the volume and some others not. And so on. Yes, this is predicted to happen (in very rare universes) in the Many Worlds Interpretation (MWI). It's also predicted to happen under the Copenhagen Interpretation (CI), you'd just have to wait a very long time to expect to see such a violation of the 2nd law of thermodynamics. From all these examples we should deduce that, if all the infinite observers we have considered took advantage of the same approach we have, they would obtain very different interpretations. So the model seems to admit in itself the chance of being wrong. It is consistent with its foundamental hypotheses the fact that it is inconsistent. So here we have the paradox. But shall we put into discussion our experimental method just because some unlucky observers are not in the condition to understand the universe and the way it works? To answer this question I have tried to go even further with my reflection. I believe we have no reason to think of being privileged observers just because we observe the universe moving according to our physical laws. Moreover, physics has been formunlated just starting from our observations, so it is clear that our models come out to be consistent with them. If these observations were not like that, we would discard them. But the same thing would be valid for all the other infinite observers and any of them could think of being privileged. Besides, from one day to another, we could also realize that all our models are no longer valid. What would happen if we lived in an Hubble sphere in which, by chance, entropy began to lower all of a sudden? We can call these universes where strange things that seem forbidden by our statistical laws of physics (which are not fundamental) happen regularly through shear chance 'magical'. I believe your question could be rewritten, is there any evidence that we are not living in such a 'magical' universe ourselves? You are quite right that any particular physical law you could construct *could* be the result of observing quantum statistics which have been skewed in one way or another. For instance, you could be in a 'magical' universe where gases don't expand in line with the predictions of our statistical mechanics/thermodynamics. Instead, you would draw up your own set of laws to describe this behaviour, assuming that the deviations happen in a systematic way. Or you could be in another 'magical' universe where even fundamental particles obey totally different equations of motion, as a result of skewed sampling on every microscopic observation of the wavefunctions concerned. In order to formulate these laws, the deviations would have to be systematic. Universes admitting such 'magical' laws would be very much rarer than those where the deviations do not permit systematic modelling to occur. The evidence that we are not in such a 'magical' universe is this. Though our laws describing the behaviour of gases etc. were originally derived from observations of large amounts of gases - macroscopic investigation - we have since found that they are 100% bconsistent with our observations of single particles of gas - microscopic investigation. In 'magical' universes, we would not expect this consistency. Observations of large amounts of gas would not be consistent with measurements made on individual particles in the vast majority of these universes. The fact that these two sets of laws of physics are consistent indicates that we are not in a 'magical' universe with very high confidence - because if we were in a 'ma
Re: a possible paradox
Hal Finney writes: > What is the paradox here? Are you saying that our deduction that we > live in a level 1 multiverse (i.e. one which is infinitely large and > full of stars and planets much like our own) is possibly wrong? That > may be true but it doesn't strike me as a paradox. All of our > reasoning is potentially wrong; we may be delusional, we may be > misinterpreting our results, we may be unlucky and atypical (for > example, earthlike planets may be enormously less likely than we > imagine). The possibility of being wrong is fundamental to scientific > and philosophical inquiry. I don't see that this new source of > potential wrongness rises to the level of a paradox. 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. > The problem with this reasoning is that there are many more observers > who see the laws of physics violated only rarely than those who see > them violated continually. Let's suppose that suddenly we start > observing a violation, like suddenly we get a 6 every time anyone > throws a dice. Now, looking forward, there are universes where that odd > behavior > continues forever, and universes where that behavior stops and we go > back to the normal laws of probability. The point is that the second > set of universes is overwhelmingly more numerous than the first. (If > you are concerned about comparing infinite universes, consider looking > at a large but finite volume of the universe, as the volume goes to > infinity.) > > So in fact we would be correct at every point to expect the normal laws > of physics to resume, because enormously more copies of ourselves will > find that to happen than those who find the violations to continue. I believe the point is that we think "the second set of universes is overwhelmingly more numerous than the first" because we live in THIS universe. But if we lived in another part of our multiverse we would think in a completely different way and no a priori principles can tell us when one is right. Federico Marulli
Re: a possible paradox
Federico Marulli writes: > I am an Italian student of Cosmology and it is the first time I write > something in this mailing list. I didn't have the time to read all your > messages, so I don't know if my thought about multiverses is a new one or > not. Anyway I would like to propose you my reflection about this topic. Welcome to the list! > My reasoning is rather simple. Dealing with an infinite level 1 > multiuniverse, if an event, even an improbable one, doesn't violate any > pshysical laws, it necessarly has to happen infinite times and in infinite > different points of the space. I think your reasoning is valid, there will be observers who see various physical laws being violated. However I disagree with some of your conclusions: > From all these examples we should deduce that, if all the infinite > observers we have considered took advantage of the same approach we have, > they would obtain very different interpretations. So the model seems to > admit in itself the chance of being wrong. It is consistent with its > foundamental hypotheses the fact that it is inconsistent. So here we have > the paradox. But shall we put into discussion our experimental method just > because some unlucky observers are not in the condition to understand the > universe and the way it works? What is the paradox here? Are you saying that our deduction that we live in a level 1 multiverse (i.e. one which is infinitely large and full of stars and planets much like our own) is possibly wrong? That may be true but it doesn't strike me as a paradox. All of our reasoning is potentially wrong; we may be delusional, we may be misinterpreting our results, we may be unlucky and atypical (for example, earthlike planets may be enormously less likely than we imagine). The possibility of being wrong is fundamental to scientific and philosophical inquiry. I don't see that this new source of potential wrongness rises to the level of a paradox. > At last we could object that all of this is admitted by our own model > and, if this absurdity really happened, we should only notice that we live > in a very improbable universe. But if it was true, it would be completely > unuseful for us to keep our mathematics and physics. For instance, if we > started, by chance, to obtain number 6 any time we throw a die, and if > this would be like that till the end of time, it would be unuseful for us > to go on considering the theory of probability as valid. There would be no > sense for us to think of having 1/6 of chances to obtain number 6, seen > that we would obtain it in any case. The problem with this reasoning is that there are many more observers who see the laws of physics violated only rarely than those who see them violated continually. Let's suppose that suddenly we start observing a violation, like suddenly we get a 6 every time anyone throws a dice. Now, looking forward, there are universes where that odd behavior continues forever, and universes where that behavior stops and we go back to the normal laws of probability. The point is that the second set of universes is overwhelmingly more numerous than the first. (If you are concerned about comparing infinite universes, consider looking at a large but finite volume of the universe, as the volume goes to infinity.) So in fact we would be correct at every point to expect the normal laws of physics to resume, because enormously more copies of ourselves will find that to happen than those who find the violations to continue. Hal Finney
