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#181
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Low carb diets
"Wayne S. Hill" wrote in message ... Elzinator wrote: "OmegaZero2003" wrote... This is very similar to the issues facing cancer researchers. Three very different mechanisms/theories using separate processes all interacting to produce the endpoint. Biological systems are more complex than most realize: feedback loops, negative and positive regulators, redundant and overlapping pathways, etc. And, they're all nonlinear. Well - theyt are not *all* non-linear! That is, they are rife with thresholds and saturation effects. This makes them very, very (very) complicated, but has a lot to do with their effectiveness and robustness. The property of non-linearity has less to do with properties of robustness (robustness connotes graceful degradation upon error, no single point of failure and survival in nonhomogeneous scenarios/contexts/environments) and effectiveness (effective for what?), than that of being dynamical and complex. In fact, it is mathematically more problematic for a non-linear system to hold coherence (e.g., biodynamics, soliton quantum lattices and soliton binding energies), than for a linear system to do so in the face of perturbation. However, what non-linear dynamical systems *do* exhibit vs linear systems, is the propensity for forming function/properties that are emergent, synergistic or both; i.e., unable to be cast into the froth of the eliminative materialists and reductionists with any expectation of success due to the inforamtion_lossy process that reduction is. Now, it is the case that certain non-linear systems have the robustness and effectiveness properties you mention; but if you go deep into this matter, I think you will find that such system have subsystems (linear) that enable the robust functionality (you do not want either a far-from-equilibrium system or a non-linear system in charge of foundational biophysics for example, when linear feedback will suffice), or the effectiveness of the system in an environmental context. And it is the overall systemic complexity of systems that happen to have non-linear subsystems, that more determines their funtional effectiveness. It is the complexity of emergent dissapative structures that will lead to robustness and effectiveness directly, not the property of having processes that are describbale using PDEs/DDEs/etc *per e*. I.e., ther are lots non-linear systems that are either chaotic, far-from equlibrium, or do not exhibit either robust dynamics or effectiveness in dealing with perturbation. See Nonlinear Science - Emergence and Dynamics of Coherent Structures by Alwyn Scott (A master in this area - I have spoken with him a lot over the years.) http://www4.oup.co.uk/isbn/0-19-850107-2#contents -- -Wayne |
#182
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Low carb diets
"Elzinator" wrote in message ... I don't agree. There is a threshold where insulin tissues can be saturated, but a healthy individual would have to eat a buttload of carbs ... Is this what a tossed salad means on the menu at Gay nightclubs? |
#183
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Low carb diets
OmegaZero2003 wrote:
"Wayne S. Hill" wrote... Elzinator wrote: "OmegaZero2003" wrote... This is very similar to the issues facing cancer researchers. Three very different mechanisms/theories using separate processes all interacting to produce the endpoint. Biological systems are more complex than most realize: feedback loops, negative and positive regulators, redundant and overlapping pathways, etc. And, they're all nonlinear. Well - theyt are not *all* non-linear! Actually, if you want to argue mathematics, they are *all* nonlinear, because linearity is such a special case that is never achieved in practice. 8-p I won't argue the rest here, except to say that my statement stands: the threshold and saturation phenomena so common in biological systems are related to the robustness of their operation. -- -Wayne |
#184
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Low carb diets
"Wayne S. Hill" wrote in message ... OmegaZero2003 wrote: "Wayne S. Hill" wrote... Elzinator wrote: "OmegaZero2003" wrote... This is very similar to the issues facing cancer researchers. Three very different mechanisms/theories using separate processes all interacting to produce the endpoint. Biological systems are more complex than most realize: feedback loops, negative and positive regulators, redundant and overlapping pathways, etc. And, they're all nonlinear. Well - theyt are not *all* non-linear! Actually, if you want to argue mathematics, they are *all* nonlinear, because linearity is such a special case that is never achieved in practice. 8-p AND I LOVE to argue or debate or discuss Mathematics. Why, me and my trusty Mathematica app have been through many wars together. Akk Steven Wolfram about what that might mean. You must be dreaming of another dimension. Lineararity and non-linearity are different concepts *in principle*. Qualitatively. In practice as you say, given that measurement is an approximation, and given that linearity lay on one extreme of a spectrum and total (what ever that can mean), the other extreme, it may be the case that all of nature exhibits non-linearity in the various processes that constitute its form and function. However, given category logic, one can see that at one point some distance off the non-linear extreme to the extreme, would constitute "non-linearity" in a given context. Ditto linearity. That is where the principles play a part - in determining where to place the points and what to consider in placing thouse points Now, it is likely a tuplpe of considering complexity. Indeed, in practice, if you are considering very low level desciptions (in terms of particle physics), one need only look at the Lagrangian, for a complex system, and visualize that alongside several other system-characteristic_describing "equations", and one has some work to do! I won't argue the rest here, except to say that my statement stands: the threshold and saturation phenomena so common in biological systems are related to the robustness of their operation. Related perhaps - but correlation DNE cause or a particularly close relationship in any dimension. But I also note that you say it is the robustness of the system is relarted to some "threshold and saturation phenomena". That is different than your first postulation. Which was: "And, they're [biological systems in nature] all nonlinear. That is, they are rife with thresholds and saturation effects. This makes them very, very (very) complicated, but has a lot to do with their effectiveness and robustness." That non-linearity itself has a lot to do with thier effectiveness and robustness. Perhaps you can elaborate. I would like to know what you thin thresholds and saturation effects have to do with linearity such that they help constitute a property or process of robustness and effectiveness. Note that specifying the system/domian will help establish criteris with which to robustness and effectiveness can be defined and measured. thresholds and saturation effects. This makes them very, very (very) complicated, but has a lot to do with their effectiveness and robustness I agree with your implicate approval of Elzi's take on such systems in general though. -- -Wayne |
#185
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Low carb diets
OmegaZero2003 wrote:
"Wayne S. Hill" wrote: Actually, if you want to argue mathematics, they are *all* nonlinear, because linearity is such a special case that is never achieved in practice. 8-p AND I LOVE to argue or debate or discuss Mathematics. Why, me and my trusty Mathematica app have been through many wars together. Akk Steven Wolfram about what that might mean. Go argue it with him. Some people think he's really onto something, but I have my doubts. You must be dreaming of another dimension. I see dead dimensions. Lineararity and non-linearity are different concepts *in principle*. Qualitatively. In practice as you say, given that measurement is an approximation, and given that linearity lay on one extreme of a spectrum and total (what ever that can mean), the other extreme, it may be the case that all of nature exhibits non-linearity in the various processes that constitute its form and function. However, given category logic, one can see that at one point some distance off the non-linear extreme to the extreme, would constitute "non-linearity" in a given context. Ditto linearity. OK, you can *sometimes* view a complex system as quasi-linear around an operating point (but in some systems this is literally useless), but even such systems can only be viewed as piecewise linear. Ultimately, the system changes as you move away from the operating condition, so what has linearization taught you? I won't argue the rest here, except to say that my statement stands: the threshold and saturation phenomena so common in biological systems are related to the robustness of their operation. Related perhaps - but correlation DNE cause or a particularly close relationship in any dimension. But I also note that you say it is the robustness of the system is relarted to some "threshold and saturation phenomena". That is different than your first postulation. Which was: "And, they're [biological systems in nature] all nonlinear. That is, they are rife with thresholds and saturation effects. This makes them very, very (very) complicated, but has a lot to do with their effectiveness and robustness." No, you're misreading me. I said the same thing both times. That non-linearity itself has a lot to do with thier effectiveness and robustness. It does, but the nature of the nonlinearity has a lot to do with it. Perhaps you can elaborate. I would like to know what you thin thresholds and saturation effects have to do with linearity such that they help constitute a property or process of robustness and effectiveness. I really don't want to get into this too deeply (not why I come here), but threshold and saturation phenomena remap an infinite range of possibilities into a modest finite range. Since a biological system can only act within such a range, this permits the system to respond to very broad ranges of environments. The system does this by employing different mechanisms or strategies in different ranges of external influence (with each mechanism triggered by its own threshold, and limited by saturation). For example, for a room- temperature environment, the body maintains core temperature using different strategies than in very cold or very hot conditions. Note that this is what makes neural networks into computational engines. Without threshold and saturation phenomena, a NN would be useless. -- -Wayne |
#186
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Low carb diets
"Wayne S. Hill" wrote in message ... OmegaZero2003 wrote: "Wayne S. Hill" wrote: Actually, if you want to argue mathematics, they are *all* nonlinear, because linearity is such a special case that is never achieved in practice. 8-p AND I LOVE to argue or debate or discuss Mathematics. Why, me and my trusty Mathematica app have been through many wars together. Akk Steven Wolfram about what that might mean. Go argue it with him. Some people think he's really onto something, but I have my doubts. I would not argue with Steve; he is onto something. He put it all together and formulated another view of reality consistent with certain other current views, yet enabling a look at complexity_from_simplicity that has heretofore not been appreciated in its scope of applicability. You must be dreaming of another dimension. I see dead dimensions. Dimensions see multiple dead yous. Lineararity and non-linearity are different concepts *in principle*. Qualitatively. In practice as you say, given that measurement is an approximation, and given that linearity lay on one extreme of a spectrum and total (what ever that can mean), the other extreme, it may be the case that all of nature exhibits non-linearity in the various processes that constitute its form and function. However, given category logic, one can see that at one point some distance off the non-linear extreme to the extreme, would constitute "non-linearity" in a given context. Ditto linearity. OK, you can *sometimes* view a complex system as quasi-linear around an operating point (but in some systems this is literally useless), but even such systems can only be viewed as piecewise linear. Ultimately, the system changes as you move away from the operating condition, so what has linearization taught you? I won't argue the rest here, except to say that my statement stands: the threshold and saturation phenomena so common in biological systems are related to the robustness of their operation. Related perhaps - but correlation DNE cause or a particularly close relationship in any dimension. But I also note that you say it is the robustness of the system is relarted to some "threshold and saturation phenomena". That is different than your first postulation. Which was: "And, they're [biological systems in nature] all nonlinear. That is, they are rife with thresholds and saturation effects. This makes them very, very (very) complicated, but has a lot to do with their effectiveness and robustness." No, you're misreading me. I said the same thing both times. I copied and pasted your original statement. That non-linearity itself has a lot to do with thier effectiveness and robustness. It does, but the nature of the nonlinearity has a lot to do with it. What does that mean? Perhaps you can elaborate. I would like to know what you thin thresholds and saturation effects have to do with linearity such that they help constitute a property or process of robustness and effectiveness. I really don't want to get into this too deeply (not why I come here), but threshold and saturation phenomena remap an infinite range of possibilities into a modest finite range. Since a biological system can only act within such a range, this permits the system to respond to very broad ranges of environments. The possible system states have little to do with whether a system is linear or non-linear. However, complextity is all about such. The system does this by employing different mechanisms or strategies in different ranges of external influence (with each mechanism triggered by its own threshold, I agree with this. But how does that (threshold and saturation) affect robustness and saturation directly. They are parameters constraining response yes and I get your point here, but a response to a perturbation using, say, Green's Theroem to determine such (where the result of solved SPDEs will eventually converge to zero - meaning the system will reach a minima on a mapping - energy/complexity/activity/etc), in terms of its robustness to that perturbation (ability to so converge/relax), will not have threshold and saturation terms in those equations. Similarly for the effectiveness parameter(s) (again, in tems of? meeting a goal (if an intensional system), surviving an environment?) . If what you mean *is* a system's effectiveness in surviving perturbations of an environment without becoming unstable, there are aharmonic mutivibrator-characterized systems that can tend to chaos or to stable systems with zippo to do with. There are many other complex systems that do not reach such extrema (saturation) in their response, nor are they especially threshold-based system. For example, the brain can detect one photon of light (via the VC) when such impinges upon a photoreceptor. That is the smallest threshold one can imagine - a pseudo-infinitely-small threshold in the *sense* that it is representative of the quanta of em energy. No telling if any brain has actually detected *only* one photon at a "time" of course, but the point is one of threshold-based systems. You have to make a quantum leap to get to that threshold arr, arr! There are also discontinuous processes that "jump" right over "thresholds". Can you point me to a ref. where you are reading/getting this relationship from? and limited by saturation). For example, for a room- temperature environment, the body maintains core temperature using different strategies than in very cold or very hot conditions. Note that this is what makes neural networks into computational engines. That is one level of description - or -one view of what brain does among several. I have a bit of experience constructing ANNs for process control and there are levels of description of brain that are not also characterizable as a TME (Turing Machine Equivalent). Without threshold and saturation phenomena, a NN would be useless. Threshold is apparent in the neuronal characterization of all-or-nothing firings (which itself is a function of humongous complexity); however, that one aspect of the messenger processes (first or second) of the brain. I cannot see where it has the import ascribed WRT robustness or effectiveness (towards a goal for example). Saturation is an example of an extrema - a perturbation causing a behavior point, and subsequent behavior points that are the same or similar magnatude until the system relaxes. The system simply has no differential response to continuing stimula. Again, this is orthogonal to robustness and effectiveness of a system (in terms of - we have not defined except as my intial take on what each means earlier. Here is another thought. Man-made complex systems are engineered, usually, to clamp to a safe value(s), all those parameters that may compromise safety or efficiency/waste-control. That, and the other characteristics I mentioned (no single point of failure, graceful degradation etc.) make a system robust (in the face of error or failure). Threshold and saturation are not part of that consideration except as knowledge that can be employed to determine startpopints (states), endpoints (end states), and the PID coefficients affecting operation. When a P/I/D/PI/PD/PID process goes awry, the PID and any cascaded processes/points to which it is related/connected get reset to some clamp value(s) and a good system will transfer control to simple LL-based controllers and/or simple interlocks completely divorced from the other control system (isolatability is another aspect of robustness). A good ref on all of this is the classic N. Weiner's Cybernetics Second Edition: or the Control and Communication in the Animal and the Machine Any good book on control systems theory incorporating the good ole PID controller strategy should give more insight into the parameters affecting system control, especially systems with feedback. -- -Wayne |
#187
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Low carb diets
"Wayne S. Hill" wrote in message ... OmegaZero2003 wrote: "Wayne S. Hill" wrote: Actually, if you want to argue mathematics, they are *all* nonlinear, because linearity is such a special case that is never achieved in practice. 8-p AND I LOVE to argue or debate or discuss Mathematics. Why, me and my trusty Mathematica app have been through many wars together. Akk Steven Wolfram about what that might mean. Go argue it with him. Some people think he's really onto something, but I have my doubts. You must be dreaming of another dimension. I see dead dimensions. Lineararity and non-linearity are different concepts *in principle*. Qualitatively. In practice as you say, given that measurement is an approximation, and given that linearity lay on one extreme of a spectrum and total (what ever that can mean), the other extreme, it may be the case that all of nature exhibits non-linearity in the various processes that constitute its form and function. However, given category logic, one can see that at one point some distance off the non-linear extreme to the extreme, would constitute "non-linearity" in a given context. Ditto linearity. OK, you can *sometimes* view a complex system as quasi-linear around an operating point (but in some systems this is literally useless), but even such systems can only be viewed as piecewise linear. BTW, as a PS to my other answer post, here are some linear systems. - those characterizable by linear algebra. there are lots of these! - Hamiltonian oscillators and like systems. (the direction field specifically) - continuous-time systems like electrical networks, many mechanical systems - any discrete system with a transfer function whose input, response and output functions depend on one variable - any systems preserving homogeneity (output proportional to input) and superposition (a way of combining linear functions such that the result is a linear function) Even non-deterministic systems can be modeled using statistics for linear dynamics. But the main point to not be belabored is that there are linear systems on nature and manmade (1) Most systems *are* non-linear but some of those are characterizable using linear methods to some degree of accuracy; you did make something like this point. (1) Schwarz, Ralph J. and Friedland, Bernard, 1965, Linear Systems, New York: McGraw-Hill Book Company, 521 pp. |
#188
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Low carb diets
On Sun, 21 Dec 2003 06:29:45 GMT, "OmegaZero2003"
wrote: BTW, as a PS to my other answer post, here are some linear systems. - those characterizable by linear algebra. there are lots of these! - Hamiltonian oscillators and like systems. (the direction field specifically) - continuous-time systems like electrical networks, many mechanical systems Only simple RLC electrical networks fall into this category. And even then, it's just a theoretical assumption over the useful operating range. Too much current or voltage or flux will flux up your circuit. Linear electrical networks only exist on paper. - any discrete system with a transfer function whose input, response and output functions depend on one variable - any systems preserving homogeneity (output proportional to input) and superposition (a way of combining linear functions such that the result is a linear function) Even non-deterministic systems can be modeled using statistics for linear dynamics. But the main point to not be belabored is that there are linear systems on nature and manmade (1) Most systems *are* non-linear but some of those are characterizable using linear methods to some degree of accuracy; you did make something like this point. (1) Schwarz, Ralph J. and Friedland, Bernard, 1965, Linear Systems, New York: McGraw-Hill Book Company, 521 pp. --- Proton Soup "If I drink water I will have to go to the bathroom and how can I use the bathroom when my people are in bondage?" -Saddam Hussein |
#189
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Low carb diets
Proton Soup wrote:
"OmegaZero2003" wrote: BTW, as a PS to my other answer post, here are some linear systems. - those characterizable by linear algebra. there are lots of these! - Hamiltonian oscillators and like systems. (the direction field specifically) - continuous-time systems like electrical networks, many mechanical systems Only simple RLC electrical networks and their analogs in other domains fall into this category. And even then, it's just a theoretical assumption over the useful operating range. Too much current or voltage or flux will flux up your circuit. Linear electrical networks only exist on paper. Exactly. They're (essentially) linear in a linear range. -- -Wayne |
#190
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Low carb diets
OmegaZero2003 wrote:
"Wayne S. Hill" wrote... OmegaZero2003 wrote: AND I LOVE to argue or debate or discuss Mathematics. Why, me and my trusty Mathematica app have been through many wars together. Akk Steven Wolfram about what that might mean. Go argue it with him. Some people think he's really onto something, but I have my doubts. I would not argue with Steve; he is onto something. He put it all together and formulated another view of reality consistent with certain other current views, yet enabling a look at complexity_from_simplicity that has heretofore not been appreciated in its scope of applicability. That's not clear to me. No, you're misreading me. I said the same thing both times. I copied and pasted your original statement. I must have been unclear the first time, because I intended the same meaning both times. That non-linearity itself has a lot to do with thier effectiveness and robustness. It does, but the nature of the nonlinearity has a lot to do with it. What does that mean? Nonlinearity can arise in many different forms. Aside from quadratic/cubic forms, which you might call "local" nonlinearities (because the "slope" of the interaction varies locally), the global behaviors of threshold and saturation phenomena are common themes in biological systems. Perhaps you can elaborate. I would like to know what you thin thresholds and saturation effects have to do with linearity such that they help constitute a property or process of robustness and effectiveness. I really don't want to get into this too deeply (not why I come here), but threshold and saturation phenomena remap an infinite range of possibilities into a modest finite range. Since a biological system can only act within such a range, this permits the system to respond to very broad ranges of environments. The possible system states have little to do with whether a system is linear or non-linear. Au contraire. If a system is linear, it must accommodate an infinite range of input variables linearly. Thus, the output range has to be of infinite extent, and cannot exhibit different types of states. However, complextity is all about such. You've got to be careful here. I take it you're referring to complex dynamical systems that exhibit self-organizing so- called emergent behaviors. A mass of nitrogen molecules is a counter example: it never does anything "emergent", and so doesn't (normally) have distinguishably different states. That is, given N molecules in a box of size V and temperature T, it exerts a pressure P. This varies in a simple and smooth manner from above the boiling point to the neighborhood of dissociation. The difference between a "simple" complex system and one capable of self-organization is the way it approaches equilibrium in the face of large disequilibrium. The system does this by employing different mechanisms or strategies in different ranges of external influence (with each mechanism triggered by its own threshold, I agree with this. But how does that (threshold and saturation) affect robustness and saturation directly. They are parameters constraining response yes and I get your point here, but a response to a perturbation using, say, Green's Theroem to determine such (where the result of solved SPDEs will eventually converge to zero - meaning the system will reach a minima on a mapping - energy/complexity/activity/etc), in terms of its robustness to that perturbation (ability to so converge/relax), will not have threshold and saturation terms in those equations. Similarly for the effectiveness parameter(s) (again, in tems of? meeting a goal (if an intensional system), surviving an environment?) . If what you mean *is* a system's effectiveness in surviving perturbations of an environment without becoming unstable, there are aharmonic mutivibrator-characterized systems that can tend to chaos or to stable systems with zippo to do with. There are many other complex systems that do not reach such extrema (saturation) in their response, nor are they especially threshold-based system. For example, the brain can detect one photon of light (via the VC) when such impinges upon a photoreceptor. That is the smallest threshold one can imagine - a pseudo-infinitely-small threshold in the *sense* that it is representative of the quanta of em energy. No telling if any brain has actually detected *only* one photon at a "time" of course, but the point is one of threshold-based systems. You have to make a quantum leap to get to that threshold arr, arr! There are also discontinuous processes that "jump" right over "thresholds". True. Can you point me to a ref. where you are reading/getting this relationship from? Sorry, I just made it up (but it happens to be true). Remember, I see dead dimensions. and limited by saturation). For example, for a room- temperature environment, the body maintains core temperature using different strategies than in very cold or very hot conditions. Note that this is what makes neural networks into computational engines. That is one level of description - or -one view of what brain does among several. I have a bit of experience constructing ANNs for process control and there are levels of description of brain that are not also characterizable as a TME (Turing Machine Equivalent). True, but I'm referring to much simpler ensembles of neurons. The computational capability of a NN is directly traceable to the threshold and saturation characteristics of the neurons. Without threshold and saturation phenomena, a NN would be useless. Threshold is apparent in the neuronal characterization of all-or-nothing firings (which itself is a function of humongous complexity); however, that one aspect of the messenger processes (first or second) of the brain. I cannot see where it has the import ascribed WRT robustness or effectiveness (towards a goal for example). Then open your eyes. I think we're arguing past each other, something that wouldn't happen if we actually discussed this in person. Saturation is an example of an extrema - a perturbation causing a behavior point, and subsequent behavior points that are the same or similar magnatude until the system relaxes. The system simply has no differential response to continuing stimula. Right, and this is really important: beyond a narrow range, the cost of responding linearly to external stimuli would be too taxing to the organism. Consequently, the organism lets that mechanism saturate, and turns on a different one. Again, this is orthogonal to robustness and effectiveness of a system (in terms of - we have not defined except as my intial take on what each means earlier. No, it's key. Here is another thought. Man-made complex systems are engineered, usually, to clamp to a safe value(s), all those parameters that may compromise safety or efficiency/waste-control. This is a simple form of saturation. That, and the other characteristics I mentioned (no single point of failure, graceful degradation etc.) make a system robust (in the face of error or failure). Threshold and saturation are not part of that consideration except as knowledge that can be employed to determine startpopints (states), endpoints (end states), and the PID coefficients affecting operation. When a P/I/D/PI/PD/PID process goes awry, the PID and any cascaded processes/points to which it is related/connected get reset to some clamp value(s) and a good system will transfer control to simple LL-based controllers and/or simple interlocks completely divorced from the other control system (isolatability is another aspect of robustness). You don't see the analogy? A good ref on all of this is the classic N. Weiner's Cybernetics Second Edition: or the Control and Communication in the Animal and the Machine Any good book on control systems theory incorporating the good ole PID controller strategy should give more insight into the parameters affecting system control, especially systems with feedback. Well, yeah, but they provide little insight into profound nonlinearity. -- -Wayne |
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