Re: The scope of physical law and its relationship to the substitution level
On 05 Jun 2015, at 07:33, John Clark wrote: Bruno Marchal marc...@ulb.ac.be wrote: The physical device is far more complex than the algorithm, astronomically more complex, so you tell me which is a simplified approximation of which. The physical device is no more relevant to the algorithm than any other universal system. Yes, an algorithm is a simplified approximation of the way a real computer works, and in general good simplified approximations work with a large number of real world situations. And so can be indeopendent of them, and belong to another realm, like logic and arithmetic. But, actually, you are wrong. Computations have been discovered by mathematicians (who were unaware of Babbage), and computer have been constructed after. You can implement the factorial in fortran, and you can implement fortran in lisp, and you can implement lisp Correct again, but whatever language you implement your algorithm in it must be implemented in matter that obeys the laws of physics because you can't make a calculation with software alone. But the goal of making real-life computations is not our goal. Your remark remains non relevant. Eventually we will have to explain real-life appearances by an internal statistics on the computations existing in arithmetic. The level of complexity is not relevant here. It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. If you agree that the math notion of computation miss something (matter), then you agree that they are mathematical. Now, when a the Milky Way is emulated by arithmetic below our substitution level, explain me how the simulated humans can guess that matter is missing. Do you agree that the simulated john Clark will still complain that matter is missing in computation, despite we know that he refers to number relations, without knowing it? Bruno John K Clark John K Clark -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. http://iridia.ulb.ac.be/~marchal/ -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
On 04 Jun 2015, at 19:54, John Clark wrote: On Thu, Jun 4, 2015 Bruno Marchal marc...@ulb.ac.be wrote: or A string which is not algorithmically compressible, Yes, that is a very good example of an event without a cause. Event is a physical notion. Algorithmic non compressibility is an mathematical notion. Nothing caused the 9884th digit of a random number to be a 6 rather than some other digit, and that is the one and only reason it is NOT algorithmically incompressible. But something did cause the 9884th digit of PI to be a 4 and not some other digit, and that's why PI IS algorithmically compressible. I have a counter-example to your claim. Fix a universal system. It determines completely its Chaitin number, yet it is algorithmically incompressible. Same with Post number: that one is compressible, yet most of its digital are not computable, although completely deterlmined, if you agree that a close machine (a machine activated on some input) either stop or does not stop. But that is not yet proven too, as comp implies there is something non computable, but it might be just the FPI and the quantum FPI confirms this. I don't care, I'm not interested in comp or of the Foreign Policy Institute. If you don't care, you would abandon the idea of showing that comp1 does not imply comp2 And I'm even less interested in comp1 and comp2 whatever the hell they are supposed to be. In some post you argued once that comp1 is trivial, and that we need to be irrational to believe in the negation of computationalism. So you start again your dismissive rhetorical maneuvers. Physics use a lot of non computable things in the background. Name one. The set of real numbers. If time or space is quantized as most physicists think it is then the real numbers are just a simplified approximation of what happens in the physical world. Typically, physical quantization is defined by using complex numbers. Even mathematicians are starting to have reservations about the real numbers, even Gregory Chaitin has started to distrust them and ironically his greatest claim to fame came from discovering (or maybe inventing) a particular real number, the Omega. Mathematicians have some problem with the real numbers since the beginning. Most are solved by method usuallu judged to rough, like an axiomatic set theory, etc. It is on analysis that intuitionist mathematics and clmassical mathematics differ the most. In theoretical computer science we can justify the needs of non constructive method, as very often there is provably no constructive tools available, and it is part of the subject. But again, the point was just that CT does not refer to physics. And yes CT entails incompleteness and the existence of non computable functions and of algorithmically non soluble problems. It is intuitively obvious that no computation can be made without the use of matter that obeys the laws of physics. made is ambiguous. Bullshit. Did you mean made in the physical reality, by a physical universal machine, Of course I mean that! or did you mean made by a immaterial universal machine, like Robinson Arithmetic? Of course I don't mean that, unless you know how to build a immaterial machine with material! Couldn't you have figured this out by yourself? It is easy to implement an immaterial machine with matter, like you can represent the abstract number 2 with two pebbles. I say that computationalism is false, because you use primitive matter. Computationalism says you can make matter behave intelligently if you organize it in certain ways, That is a rephrasing of computationalism, and what you say follow from it, but the more precise and general version is that you stay conscious (and don't see any difference) when simulated at the right level (which existence is assumed), and that will entail that we can't distinguish a physical computation from a purely arithmetical one, by pure introspection (without clues from observation). maybe that matter is primitive and maybe it is not but there has been a enormous amount of progress in recent years with AI demonstrating that Computationalism is probably true. There has been zero progress demonstrating that mathematics can behave intelligently. Mathematics does not belong to the category of things which can behave. But mathematics, and actually just arithmetic, can define relative entities behaving relatively to universal number, and that is known since Post, Turing, etc. Why should we abandon computationalism, given that nobody has ever show the existence of primitive matter? Nobody has shown the existence of primitive mathematics either. Primitive means that we have to assume it. Logicians have prove that arithmetic, or universality, is primitive in the sense that you cannot derive arithmetic, or the existence
Re: The scope of physical law and its relationship to the substitution level
On 05 Jun 2015, at 06:59, John Clark wrote: On Thu, Jun 4, 2015 , Bruno Marchal marc...@ulb.ac.be wrote: The point is just that the notion of computation, once you agree with Church-Turing thesis, is made into a purely arithmetical notion. That is incorrect. The Church-Turing thesis says that a function on the positive and negative integers is computable if and only if it is computable on a Turing Machine; and if the Turing Machine is not made of matter that obeys the laws of physics then the machine is useless because it does absolutely positively nothing. I begin to think that you are attempting to become the champion of nonsense. Turing machine are not made of matter, and computation is definable in arithmetic, just using the symbol s, 0, + * and the usual logical symbol. We can even eliminate the A (for all) quantifier. You can define computable and finite piece of computation by one precise combinators, or one precise number, or one precise diophantine polynomials, etc. YOU CAN'T MAKE A COMPUTATION WITH A DEFINITION!! But the point is that we dont have to made them once you agree that 2+2=4 does not depend on matter, and that is the case, by definition of the notions involved. You are the one invoking some God (Matter) capable of making some computation more real than others. It could not be clearer that some calculations ARE more real than others. Relatively? Sure. I have to pay by national taxes, that's real and important to avoid real problems, but that is not relevant. Again, you beg the question if you say that the physical computations are more real. you could say that only those blessed by the Pope are really real ... Matter can make calculations that I can see, but your calculations are invisible; Like the numbers. But in the computation which exist in arithmetic, some emulate person seeing object. You could say that there is no real driving car, or any movement, in a block-universe, as there is no time there, and we need time to measure the presence of movement. But we have no problem because those notions are relative. Similarly here. That is why the notions of points of view is capital in the computationalist approach. the transubstantiation in the Catholic Mass that turns bread and wine into the body and blood of Jesus Christ is also invisible. As I've said, being invisible and being nonexistent look rather similar Assuming some aristotelian theological dogma. comp, explains the physical, from machine self-referential properties, and so can be translated in arithmetic to give the proposition logic of physics. I don't care, I'm not interested in comp. Then why do you participate in this list where comp and its (meta)- physical consequences are discussed since about 20 years? - You agree with the multiverse. Some (rare) physicists have criticized my thesis (without reading it) because they were told that I defend Everett, and that was enough for them, (which, btw, is false, as I do not defend any thesis). - You agree with comp, and might be said being, like Hal Finney, a real comp practitioners. - You agree that physics might not be fundamental. So what? You would disagree only because you would have found a flaw in step 3, without ever being able to convince anyone on this? or because, CT would use physics? (But you have not find serious confirmation on this on the net, and still deny). or you want just be disagreeable? or what? I tell you that I can decompose step 3 in smaller steps, ... but recently, even 14 years old children told me that this was necessary only for the 12 years old one! Indeed, if you take the definition which are given, this is 3p obvious (and you said so yourself), so nobody in this list or elsewhere understand why you don't move on the other steps. Yet, you keep the tone everyone know that this is just peepee. That shows that it is purely rhetorical dismiss. I am not sure I can see what is your problem. It does look personal, given the constant ad hominem way of addressing the posts. Bruno John K Clark -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. http://iridia.ulb.ac.be/~marchal/ -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at
Re: The scope of physical law and its relationship to the substitution level
On 6/4/2015 10:33 PM, John Clark wrote: Bruno Marchal marc...@ulb.ac.be mailto:marc...@ulb.ac.be wrote: The physical device is far more complex than the algorithm, astronomically more complex, so you tell me which is a simplified approximation of which. The physical device is no more relevant to the algorithm than any other universal system. Yes, an algorithm is a simplified approximation of the way a real computer works, and in general good simplified approximations work with a large number of real world situations. You can implement the factorial in fortran, and you can implement fortran in lisp, and you can implement lisp Correct again, but whatever language you implement your algorithm in it must be implemented in matter that obeys the laws of physics because you can't make a calculation with software alone. The level of complexity is not relevant here. It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. The trouble with this argument is that the laws of physics are mathematical abstractions. Brent -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
On Fri, Jun 5, 2015 Bruno Marchal marc...@ulb.ac.be wrote: Event is a physical notion. Algorithmic non compressibility is an mathematical notion. An event is just a place and a time; are you saying that mathematics is incapable of handling 4 coordinates? Nothing caused the 9884th digit of a random number to be a 6 rather than some other digit, and that is the one and only reason it is NOT algorithmically incompressible. But something did cause the 9884th digit of PI to be a 4 and not some other digit, and that's why PI IS algorithmically compressible. I have a counter-example to your claim. Fix a universal system. It determines completely its Chaitin number, yet it is algorithmically incompressible. I don't know what you mean by fix but if something requires an infinite number of steps to determine what it will do its not very deterministic. In some post you argued once that comp1 is trivial, Bullshit. I have never argued anything about comp1 and never will because I'm sick to death with comp of any variety. If time or space is quantized as most physicists think it is then the real numbers are just a simplified approximation of what happens in the physical world. Typically, physical quantization is defined by using complex numbers. Because even if space and time are quantized the discrete steps are so little that complex numbers are a good approximation of the physical world unless you're dealing with things that are ultra super small. But again, the point was just that CT does not refer to physics. Bullshit. Computationalism says you can make matter behave intelligently if you organize it in certain ways, That is a rephrasing of computationalism, and what you say follow from it, but the more precise and general version is that you stay conscious [...] To hell with consciousness! Figure out how intelligence works and then worry about consciousness. maybe that matter is primitive and maybe it is not but there has been a enormous amount of progress in recent years with AI demonstrating that Computationalism is probably true. There has been zero progress demonstrating that mathematics can behave intelligently. Mathematics does not belong to the category of things which can behave. That is a HUGE admission on your part, if it is true (and I don't know if it is or not) then the debate is over and physics is more fundamental than mathematics. End of story. But mathematics, and actually just arithmetic can define relative entities behaving relatively to universal number And I can define a new integer that has never been seen before, I call it fluxdige and it's definition is that it's equal to 2+2 but it's not equal to 4. You can't make a calculation with a definition! Nobody has shown the existence of primitive mathematics either. Primitive means that we have to assume it. Logicians have prove that arithmetic, or universality, is primitive in the sense that you cannot derive arithmetic, or the existence of universal numbers, without assuming less than that. When Peano came up with the integers he had to first assume that the number 1 existed and then he came up with rules to generate its successor, but if the physical universe did not exist, if there were ZERO things in it, then it's not at all obvious that the number 1 would exist. Maybe it would and maybe it wouldn't, I don't know. One of your Greek buddies Socrates said that the first step toward wisdom is knowing when you don't know. So if Socrates was right then I'm wiser than you are. Computations have been discovered in mathematics. All textbooks in the filed explains that. You can't make a computation with a textbook! You can't make a calculation with a definition! You can. Then stop talking about it and just do it! And if it is simple enough, you can do that mentally. You will tell me that in this case we still need a physical brain Indeed I will. but this can be a local relative notion, Local? A good rule of thumb is that if a theory says Local means the entire multiverse then things may be getting out of hand. I say compute means figuring out an answer, nobody has ever done this without using matter that obeys the laws of physics. You are right, but this does not prove that the notion of matter is used in the definition of computation. Who cares about the damn definition? You can't make a computation with a definition! To do something materially we need matter Yes, but if mathematics is more fundamental than physics it's not obvious why that should be the case. PA and formal systems compute things without doing the computation physically. Bullshit. Kleene invented his famous predicate and got his normal form theorem for the computable function by using the arithmetical existence of the computations only. Then why isn't there a Kleene Computer Corporation with a trillion dollar valuation? If you know how to make
Re: The scope of physical law and its relationship to the substitution level
On Fri, Jun 5, 2015 at 8:15 AM, Bruno Marchal marc...@ulb.ac.be wrote: Turing machine are not made of matter, If it's not made of matter then it's not a machine it's a Turing Something and it can't do a damn thing. and computation is definable in arithmetic, just using the symbol s, 0, + * and the usual logical symbol. YOU CAN'T MAKE A COMPUTATION WITH A DEFINITION!! But the point is that we dont have to made them once you agree that 2+2=4 does not depend on matter, But I don't agree that must be true, it's the very point we're debating. If 4 physical things did not exist in the physical universe or even 2 I don't know if 2+2 would equal 4 or not and neither do you. If it does then mathematics is more fundamental if it doesn't then physics is. John K Clark -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
On Fri, Jun 5, 2015 Bruno Marchal marc...@ulb.ac.be wrote: Do you agree that the simulated john Clark will still complain that matter is missing in computation, despite we know that he refers to number relations, without knowing it? If the simulation had been done correctly then the simulated John Clark will have the same opinions I do including reservations about computations being made without matter. If the simulation was being performed on a computer made of matter then the reservations were justified, if the simulation was being performed by pure mathematics and nothing else then they were not. John K Clark -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Notion of (mathematical) reason
Hi Bruno: You made this statement recently in the scope of physical law thread . There is no event notion in mathematics, nor is there any notion of cause, unless you enlarge the notion of cause to the notion of (mathematical) reason. . You appear to be stating that mathematics exists in a timeless universe (no event notion), which makes sense. This would leave mathematics in a role of modeling/describing or measuring both instantiations of causes and their effects/events. You further refer to the notion of (mathematical) reason. Question: If chains of causes are preceded by chains of reasons (and your reference to mathematics) doesn't that infer some form of duality? IOW, the duality being (a) abstract reasons (that precede causes) and (b) their complementary realities (effects/events). Thanks. Pzomby -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
On 6/5/2015 12:22 PM, John Clark wrote: On Fri, Jun 5, 2015 , meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. The trouble with this argument is that the laws of physics are mathematical abstractions. Mathematicians are always saying that mathematics is a language, but what would be the consequences if that were really true? The best way known to describe the laws of physics is to write then in the language of mathematics, but a language is not the thing the language is describing. I agree the laws of physics are descriptions we invent; but even so they are abstractions and not material and what they define is only an approximation to what happens in the world. That's what makes them useful - they let us make predictions while leaving out a lot of stuff. Brent A book about Napoleon may be written in the English Language, but the English Language is not Napoleon and mathematics may not be the physical universe. Or maybe it is. As I've said many times I'm playing devil's advocate here, maybe mathematics really is more fundamental than physics but if it is it has not been proven. John K Clark -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com mailto:everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com mailto:everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
On Fri, Jun 5, 2015 , meekerdb meeke...@verizon.net wrote: It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. The trouble with this argument is that the laws of physics are mathematical abstractions. Mathematicians are always saying that mathematics is a language, but what would be the consequences if that were really true? The best way known to describe the laws of physics is to write then in the language of mathematics, but a language is not the thing the language is describing. A book about Napoleon may be written in the English Language, but the English Language is not Napoleon and mathematics may not be the physical universe. Or maybe it is. As I've said many times I'm playing devil's advocate here, maybe mathematics really is more fundamental than physics but if it is it has not been proven. John K Clark -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
On 6 June 2015 at 07:22, John Clark johnkcl...@gmail.com wrote: On Fri, Jun 5, 2015 , meekerdb meeke...@verizon.net wrote: It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. The trouble with this argument is that the laws of physics are mathematical abstractions. Mathematicians are always saying that mathematics is a language, but what would be the consequences if that were really true? I'm not sure that mathematicians say this (well, Galileo did, iirc, but generally they don't). The best way known to describe the laws of physics is to write then in the language of mathematics, but a language is not the thing the language is describing. A book about Napoleon may be written in the English Language, but the English Language is not Napoleon and mathematics may not be the physical universe. Or maybe it is. As I've said many times I'm playing devil's advocate here, maybe mathematics really is more fundamental than physics but if it is it has not been proven. I doubt anything could prove this if it's still being debated even though physics has been based on maths for 300 years. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
On 6 June 2015 at 09:46, meekerdb meeke...@verizon.net wrote: On 6/5/2015 12:22 PM, John Clark wrote: On Fri, Jun 5, 2015 , meekerdb meeke...@verizon.net wrote: It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. The trouble with this argument is that the laws of physics are mathematical abstractions. Mathematicians are always saying that mathematics is a language, but what would be the consequences if that were really true? The best way known to describe the laws of physics is to write then in the language of mathematics, but a language is not the thing the language is describing. I agree the laws of physics are descriptions we invent; but even so they are abstractions and not material and what they define is only an approximation to what happens in the world. That's what makes them useful - they let us make predictions while leaving out a lot of stuff. I know what you mean, but this statement could be considered a bit misleading. Unlike the other branches of science, physics at least tries to be a complete description. Of course it fails in practice, but (very much in theory) a TOE would describe everything - it would in principle be like Laplace's demon (though possibly only for a multiverse). -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Notion of (mathematical) reason
On 6 June 2015 at 11:26, Bruce Kellett bhkell...@optusnet.com.au wrote: LizR wrote: This is true if events have an existence apart from maths. However, that is still being debated. Tegmark's mathematical universe hypothesis suggests that time and events are emergent from an underlying timeless mathematical structure. To take something that is (hopefully) less contentious, the block universe of special relativity already suggests something similar to this. In relativity, all chains of events are embedded in a space-time manifold, and hence causation comes down to how world-lines are arranged within this structure. This is not true. Causality is still a fundamental consideration in SR, and that carries over into the basic structure of quantum field theory. Even within the block universe model, the light cone structure of spacetime is fundamental. The light cone encapsulates the fundamental insight of SR that causal influences cannot propagate faster than the speed of light -- the light cone is the limiting extent of causal structure. The laws of physics consistent with this structure in SR and beyond are have a (local) Lorentz symmetry, which preserves the causal structure between different Lorentz frames. The distinction between time-like and space-like separations of events is aa fundamental tenet of physical law. None of this contradicts what I said. All I am concerned with is that SR indicates that events are embedded in a 4D continuum. Describing how they're embedded doesn't change that. -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Notion of (mathematical) reason
LizR wrote: This is true if events have an existence apart from maths. However, that is still being debated. Tegmark's mathematical universe hypothesis suggests that time and events are emergent from an underlying timeless mathematical structure. To take something that is (hopefully) less contentious, the block universe of special relativity already suggests something similar to this. In relativity, all chains of events are embedded in a space-time manifold, and hence causation comes down to how world-lines are arranged within this structure. This is not true. Causality is still a fundamental consideration in SR, and that carries over into the basic structure of quantum field theory. Even within the block universe model, the light cone structure of spacetime is fundamental. The light cone encapsulates the fundamental insight of SR that causal influences cannot propagate faster than the speed of light -- the light cone is the limiting extent of causal structure. The laws of physics consistent with this structure in SR and beyond are have a (local) Lorentz symmetry, which preserves the causal structure between different Lorentz frames. The distinction between time-like and space-like separations of events is aa fundamental tenet of physical law. Bruce Presumably the arrangement has abstract reasons (i.e. what we call the laws of physics, whatever they turn out to be). So even in SR, causality in effect takes a back seat, becoming the result of how observers are embedded in a timeless structure. Of course in this case, time still exists as a dimension, as it was in Newtonian physics. But even in Newtonian physics, Laplace imagined the past and future would be already there as far as a sufficiently godlike intellect was concerned. So Newton and Einstein imagined that events were embedded in a physical structure, but that they were already there in the sense of being emergent from the laws of physics plus initial conditions. ISTM that moving causation into a purely abstract realm is just one more step in this process, and a logical one (though obviously one that needs to be tested against reality). -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
On 6/5/2015 4:29 PM, Bruce Kellett wrote: meekerdb wrote: On 6/5/2015 12:22 PM, John Clark wrote: On Fri, Jun 5, 2015 , meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. The trouble with this argument is that the laws of physics are mathematical abstractions. Mathematicians are always saying that mathematics is a language, but what would be the consequences if that were really true? The best way known to describe the laws of physics is to write then in the language of mathematics, but a language is not the thing the language is describing. I agree the laws of physics are descriptions we invent; but even so they are abstractions and not material and what they define is only an approximation to what happens in the world. That's what makes them useful - they let us make predictions while leaving out a lot of stuff. So what is this lot of stuff that the mathematical abstractions leave out? In response you your initial point that the laws of physics are mathematical abstractions, the obvious questions is Abstractions from what? Abstractions from physical events. We find we can leave out stuff like the location (and so conserve momentum) and the position of distant galaxies and the name of the experimenter and which god he prays to etc. Of course what we can leave out and what we must include is part of applying the theory. Physicists work by considering simple experiments in which they can leave out as much stuff they're not interested in as possible in order to test their theory. Engineers don't get to be so choosy about what's left out; they have to consider what events may obtain. But they also get to throw in safety factors to mitigate their ignorance. Brent Bruce -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Notion of (mathematical) reason
This is true if events have an existence apart from maths. However, that is still being debated. Tegmark's mathematical universe hypothesis suggests that time and events are emergent from an underlying timeless mathematical structure. To take something that is (hopefully) less contentious, the block universe of special relativity already suggests something similar to this. In relativity, all chains of events are embedded in a space-time manifold, and hence causation comes down to how world-lines are arranged within this structure. Presumably the arrangement has abstract reasons (i.e. what we call the laws of physics, whatever they turn out to be). So even in SR, causality in effect takes a back seat, becoming the result of how observers are embedded in a timeless structure. Of course in this case, time still exists as a dimension, as it was in Newtonian physics. But even in Newtonian physics, Laplace imagined the past and future would be already there as far as a sufficiently godlike intellect was concerned. So Newton and Einstein imagined that events were embedded in a physical structure, but that they were already there in the sense of being emergent from the laws of physics plus initial conditions. ISTM that moving causation into a purely abstract realm is just one more step in this process, and a logical one (though obviously one that needs to be tested against reality). -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
LizR wrote: On 6 June 2015 at 07:22, John Clark johnkcl...@gmail.com mailto:johnkcl...@gmail.com wrote: On Fri, Jun 5, 2015 , meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. The trouble with this argument is that the laws of physics are mathematical abstractions. Mathematicians are always saying that mathematics is a language, but what would be the consequences if that were really true? I'm not sure that mathematicians say this (well, Galileo did, iirc, but generally they don't). The best way known to describe the laws of physics is to write then in the language of mathematics, but a language is not the thing the language is describing. A book about Napoleon may be written in the English Language, but the English Language is not Napoleon and mathematics may not be the physical universe. Or maybe it is. As I've said many times I'm playing devil's advocate here, maybe mathematics really is more fundamental than physics but if it is it has not been proven. I doubt anything could prove this if it's still being debated even though physics has been based on maths for 300 years. I think you will find that physics has been based on experience, and the the experience/experiments have been codified/described by mathematics. To say that is has been based on maths is a gross distortion of the facts. Bruce -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
meekerdb wrote: On 6/5/2015 12:22 PM, John Clark wrote: On Fri, Jun 5, 2015 , meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. The trouble with this argument is that the laws of physics are mathematical abstractions. Mathematicians are always saying that mathematics is a language, but what would be the consequences if that were really true? The best way known to describe the laws of physics is to write then in the language of mathematics, but a language is not the thing the language is describing. I agree the laws of physics are descriptions we invent; but even so they are abstractions and not material and what they define is only an approximation to what happens in the world. That's what makes them useful - they let us make predictions while leaving out a lot of stuff. So what is this lot of stuff that the mathematical abstractions leave out? In response you your initial point that the laws of physics are mathematical abstractions, the obvious questions is Abstractions from what? Bruce -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: The scope of physical law and its relationship to the substitution level
meekerdb wrote: On 6/5/2015 4:29 PM, Bruce Kellett wrote: meekerdb wrote: On 6/5/2015 12:22 PM, John Clark wrote: On Fri, Jun 5, 2015 , meekerdb meeke...@verizon.net mailto:meeke...@verizon.net wrote: It's very relevant if you want to know what is a simplified approximation of what. And we both agree that a electronic computer is vastly more complex than it's logical schematic, so why can we make a working model of the complex thing but not make a working model of the simple thing when usually it's easier to make a simple thing than a complex thing? The only answer that comes to mind is that particular simplified approximation is just too simplified and just too approximate to actually do anything. That simplification must be missing something important, matter that obeys the laws of physics. The trouble with this argument is that the laws of physics are mathematical abstractions. Mathematicians are always saying that mathematics is a language, but what would be the consequences if that were really true? The best way known to describe the laws of physics is to write then in the language of mathematics, but a language is not the thing the language is describing. I agree the laws of physics are descriptions we invent; but even so they are abstractions and not material and what they define is only an approximation to what happens in the world. That's what makes them useful - they let us make predictions while leaving out a lot of stuff. So what is this lot of stuff that the mathematical abstractions leave out? In response you your initial point that the laws of physics are mathematical abstractions, the obvious questions is Abstractions from what? Abstractions from physical events. We find we can leave out stuff like the location (and so conserve momentum) and the position of distant galaxies and the name of the experimenter and which god he prays to etc. Of course what we can leave out and what we must include is part of applying the theory. Physicists work by considering simple experiments in which they can leave out as much stuff they're not interested in as possible in order to test their theory. Engineers don't get to be so choosy about what's left out; they have to consider what events may obtain. But they also get to throw in safety factors to mitigate their ignorance. In other words, in this account, the pre-existing physical world is taken as a given, from which laws are simplified abstractions. Fine, that's the way I think it is. Bruce -- You received this message because you are subscribed to the Google Groups Everything List group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
