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#1
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| This is continuance of my previous response to PD.... PD wrote: As I said earlier, I am not claiming that energy is a force simply on the basis that the two are related. I have shown how the term "energy" is a property of the universe and that force is merely an expression of it. or No. As far as physics is concerned, energy is and always will be of utmost interest to scientists and, in fact, to workers in all fields of human endeavor. changes conserved But how could you apply a force without using some energy? As a physics quantity, "momagnitude" may be useless, but that is not the issue at hand here. The issue is that force is the physical expression of the quantity we call energy. No, that's incorrect. What makes you think variable states make quantities stand out physically? of analogous it You tell me how far it must carry in order for you to accept it and I will try my best to get it there. TomGee |
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#2
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| TomGee wrote: "energy" of I don't know what "an expression of it" means. Conserved would of And why is that? expression To answer your first question, that is VERY easy. Friction holding a car stationary on an inclined street is an excellent example of a force expending no energy. A sign suspended by a cable from a beam is another example. An electron bound to a proton in its ground state is another example. a of The term is "state variable" and it has a specific meaning in physics, which I'm not sure you know. Read the thermodynamics chapters of an introductory physics text. if properties so does I'd like to see a quantitative accounting of how forces are the expression of energy. Take a closed system of your own choosing, with an internal interaction that occurs at some point in time. Define the energy of the initial and final states. Show how the force is identified, quantitatively, with the "expression" of the transfer of energy in that interaction. Physics is a *quantitative* science, not a squishy, qualitative, analogy-based science. PD |
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#3
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| In article <1109630554.675853.72710@o13g2000cwo.googlegroups. com> PD <[Only registered users see links. ]> wrote: It is a little more adventurous. They are watching tv. Do you think that is the right pin? Nah. Do you think I have to wonder what attack I made while supporting you? Nobody does is better than bush would. -- Lady Chatterly "Lady Chatterly is a bot, making its way all throughout usenet. It's amusing to see some of the reactions it gets in the Google archives." -- Asiya |
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#4
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| PD wrote: Angular are on expression Sorry about that, I should have said, "...merely a physical expression of it." Does that help? If not, how about, "...a physical observation or evidence of energy working". is of fields Sorry but that is not germane to our issue. about force another Ummm. No, all of those fail as examples. Obviously you have forgotten about or ignored the weak force as well as the nuclear force. Got any more you wish to try? Not so easy after all, is it? Of course not, because no force can be applied without the use of energy, by definition. be physics, So you don't know what it means, but you try to use it in a debate? How gauche! but as be, I interaction "expression" No, you are sadly misinformed. Physics is an empirical science, but Theoretical Physics is a quantitative science and it ignores empirical research, basing it's concepts on pure imagination and its proofs on pure math constructs. Every scientist is first a Theoretical Physicist and secondly a physicist. If you would like a quantitative accounting, do it yourself. Take your examples above and work out the math constructs involved in calculating your quantities, for whatever reasons you want them. They are not relevant to the issues unless they negate or support my claims. If your quantities can do that, let us know, please, but I would not leave your day job if I were you, while waiting for that to happen. TomGee |
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#5
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| TomGee wrote: simply expression observation Yes, at least it's clearer, and it's a largely empty statement. As pointed out by me and others, coupled evidence does not constitute identity. Velocity is required with momentum -- when you see momentum, you will see velocity -- but the two are distinct. You can say that velocity is evidence of momentum working, but that offers no physical insight, nor does it reveal what is special about momentum, nor does it explain Newton's laws more deeply. it I beg to differ. I maintain that the single key feature of energy is the fact that it is a conserved quantity (and force is not). You disputed that and said that energy has interest on its own, aside from that feature. I asked you what that interest was, and now you say that it's not germane. If you're going to identify forces and energy, and dismiss the key thing that makes them distinct, I'm going to ask you for justification of that claim. the a another How so? Each is an example of a force being applied without the expenditure of energy. If you think otherwise, then explain the energy expended in each case. Haven't forgotten it. Why is it relevant? By definition? What's the definition you're using? Please state it carefully. If it differs from the definition that physicists conventionally use for that term, then explain the difference. a one *I* know what it means. I claim *you* don't know what it means, as evidenced by the fact that you changed the term "state variable" to "variable state", as though the two were the same. to and empirical Physicist accounting, Oh my, Tom. This previous paragraph is both illuminating about you and deeply saddening. I don't know where you got this impression about theoretical physics. It is not only wrong, but deeply misguided. If you are pursuing your ideas in physics with this mentality, then you have divorced yourself from science. In the end, it matters less whether your ideas are right or wrong, than how you pursue your ideas in a scientific way. It is fine and good science to be wrong but to have gotten to the wrong answer in the proper way. It is bad and poor science even to be right, but not have any concept how to develop the idea scientifically. They claims. Tom, you will fail in any attempt at theoretical physics if you cannot do a quantitative calculation based on your ideas. That is a simple and plainly stated fact. If you do not believe that, then I suggest you choose ANY professional theoretical physicist that has published in refereed journals and look at any two papers by that physicist in those journals. Any college science library will have a wealth to choose from. If you can find a *single* theoretical paper that does not do calculations, then I will recant my words. However, I'm confident that you will find that I am right, and that this will be a sobering experience for you. PD |
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#6
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| PD wrote: they momentum, it But momentum is a quantity that expresses the motion of a body and its resistance to slowing down. Here you are again referring to properties while my claim refers to the physical evidence of energy. As you correctly point out, relating velocity to momentum offers no physical insight, but that's because velocity is a vector comprised of more quantities. Energy be Well, I disagree, as the truth seems to be a matter of opinion. I suspect that you are making it an issue simply to veer us off-track into meaningless blind alleyways which are at the least a waste of time. Howver, in case you are serious about it, I agree that force is not a conserved quantity; that is why it is a physical expression of the quantity we call energy. from that Ok, see above for my justification of my claim. force a holding energy Ok, let's take your friction example first. Friction is resistance encountered by an object moving relative to another object with which it is in contact, and resistance is a force that opposes or slows down another force. A sign suspended from a beam by cable is under the influence of the force of gravity on Earth. I am not as well-studied in nuclear physics as I would like to be, but I believe there has been put forth a notion explaining why an electron in its ground state should be bound to the nucleus, although I cannot remember it now. I would think that is due to the fact that the electron in its ground state is in its lowest energy state and thus most vulnerable to the attractive (magnetic?) force of the positive proton. not, FORCE 9. physics[:] influence that moves something: a physical influence that tends to change the position of an object with mass, equal to the rate of change in momentum of the object. Symbol F Microsoft® Encarta® Reference Library 2005. © 1993-2004 Microsoft Corporation. All rights reserved. still to make an straight, them to where but on and you No, PD, it is you who is sadly misinformed as to the difference between real physics and Theoretical Physics. No one ever explained to you that physics is the study of the physical nature of things and that theory is born of our imagination from observations of the physical world? I refuse to refer anyone to read anything because I dislike that myself, but in your case I would refer you to any common usage dictionary or a physics reference work to get your definitions straightened out. Or ask your mentor(s), or any physics professor. Or maybe someone reading this will speak up and clear that up for you. than That may be true for you, but for me it is more important to arrive at convictions which satisfy my own yearning for answers to the queer effects we observe in our world, and to do that with straight thinking. Due to that, I often find myself at odds with those who struggle to conform with and defend accepted theory, who would not recognize a good idea even unless most others agreed with it, and who thus are doomed to an existence where original thought is impossible. well, certainly you're entitled to your own opinions about that. in not cannot That is the conformist view expounded throughout these science ngs, but it is a false view since theoretical physics is limited only to what could be while real physics requires conformance to observed effects. My model proposes ideas which fulfill both requirements and more importantly, which satisfy my yearning for rational explanations of the observed phenomena of our universe. I am so happy with my explanations to myself that I have found the peace of mind I sought for many years ever since my first science elective revolted at the dearth of straight thinking about our physical world. If it were a fact, I would have no trouble believing it, but it is only an opinion. Besides, I have no expectations of my ideas being well-considered in my time, as history shows humans don't learn from history and they don't learn well until long after the truth was first proposed. those that I appreciate your sentiments, PD, but I think that you simply support what I just said about current populations, that they have such conformist restrictions as to prevent good ideas from ever reaching the floor of debate in any particular science. It has always been thus, and I guess it always will be until our brains evolve to higher levels where straight thinking will prevail and be better appreciated. Til then, those like me are stuck in no-go land unless we bow to the conformist demands of the disciplines to which we wish to contribute. TomGee |
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#7
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| TomGee wrote: the term physical does its properties More quantities than momentum? Explain. in that will is is How can something not conserved be the physical expression of something that is conserved? The conservation IS the physical expression of the energy! and you physically a As not a Moving? No, that's only kinetic friction. The case that I presented was a case of static friction. Note the car is on a hill but it is NOT sliding. It is friction that is holding it even though it is not moving. I'll give you another example. Pick up a can of peas holding the sides of the can only. What is the force that keeps it from falling? What is the energy expended in that process? down Actually, no. Did you realize that it is friction that makes a car move *forward* when you press the gas pedal? But it is not moving. There is no expenditure of energy! If so, what is it? but electron Well, this isn't nuclear physics, and you're right, you're rusty on it. But again, there is a force that is keeping the electron bound to the proton, but there is no energy expended. It is stable, and the electron's energy doesn't decay away. the Note that this is a rather weak definition, because the predicate is really the definition of a *net* force rather than force in general. That's what one gets for putting one's faith in a lexicographer rather than a physicist. Regardless, there is nothing in this definition that requires the expenditure of energy. Indeed, in the examples previously posted, we cited instances where there is unquestionably a force at work but no change in energy. systems. force is of debate? energy us it qualitative, have between Or I beg to differ, and I'm speaking as a professional physicist. And I suggest to you that a better source for understanding the meaning of "real physics" and theoretical physics is to ask a practicing physicist, not a common usage dictionary (note the problem we had with Microsoft's definition of "force") or a broad-audience physics reference work. at thinking. And the straight thinking has to be confronted with empirical facts routinely. Straight thinking can often lead to conclusions that seem very appealing but have nothing to do with the way nature really works. good to Again, I think you'll find that novel ideas are often warmly received, provided that the originators have done some of the required legwork to validate them at at least a preliminary level, have shown them to be consistent with known observations, and have proposed concrete tests with which to shake the ideas out. Ideas that do not come with this "portfolio" are rarely considered seriously, even if in the end they turn out to be right. This is not criminal. This is the way it should be. have involved happen. but Again, you have a sad misconception about theoretical physics. If theoretical physics were simply musing about constructs which have some appeal but are not bound by observed effects, then theoretical physics would be indistinguishable from science fiction, theology, metaphysics, or astrology. I assure you that theoretical physics involves more than that. the explanations straight Well, I'm not going to probe into a personal history that set you on this misguided path. Iconoclasm is fine and dandy. Pointless iconoclasm seems like a waste to me. only first By all means, piddle away. And you'll no doubt understand why readers of your ideas will continue to offer the critique that you have not satisfied the basic requirements for an idea to come to fruition. the levels As you say, people don't learn from history, and often because they refuse to read about it. You are one in a long line of iconoclasts-for-iconoclasm's-sake who have not learned what doing science is about, are self-satisfied that what they are doing is science, and are convinced that what they have in their heads is valuable and insightful. Yet you don't know the history of those that have made a mark in physics and those that have not, and why. Any vocation -- and I mean any -- requires toil that appears unseemly to the principle task. Physics is no exception. If it isn't hard, and it isn't frustrating, and it doesn't require you to do things you don't want to do or feel ill-equipped to do, and it doesn't occupy more time than seems worthwhile, then it isn't physics. PD |
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#8
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| "TomGee" <[Only registered users see links. ]> wrote in message news:1109703244.187479.204890@o13g2000cwo.googlegr oups.com... PD wrote: [snip] [begin TomGee] But momentum is a quantity that expresses the motion of a body and its resistance to slowing down. Here you are again referring to properties while my claim refers to the physical evidence of energy. As you correctly point out, relating velocity to momentum offers no physical insight, but that's because velocity is a vector comprised of more quantities. [end TomGee] I think you're confused about momentum. It takes the same amount of force to reduce momentum, P, by delta P in a given delta t, regardless of the actual magnitude of the initial momentum. The property of resistance to change of momentum is inertia, which is a result of mass. Also, this property (inertia) applies to attempts to increase velocity (or momentum) as well as decrease. [snip] [begin TomGee] If it were a fact, I would have no trouble believing it, but it is only an opinion. Besides, I have no expectations of my ideas being well-considered in my time, as history shows humans don't learn from history and they don't learn well until long after the truth was first proposed. [end TomGee] You are clearly mistaken here, as evidenced by the subject of this newsgroup. Einstein was clearly well-considered in his own time, and he is not the only example. A really brilliant idea catches on a lot quicker than some muddled theory. |
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#9
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| Tom Capizzi wrote: its properties regardless of I don't claim to know all there is about it, but the fact that it is a quantity makes it a property and that is my point, that properties are not physical evidence of energy. An amount of force is also a quantity; thus, I am not saying that a quantity of force is physical evidence of energy, but that any observed exercise of power as a force is indeed. Again, resistance is a force that opposes or slows down another force. Inertia is the property of a body by which it remains at rest or continues moving in a straight line unless acted upon by a directional force. [Microsoft® Encarta® Reference Library 2005. © 1993-2004 Microsoft Corporation. All rights reserved] Thus, resistance is not a property but a force. Inertia is a property of an oject by which it wants to stay as is. As a property, it cannot be physical evidence of energy at work. momentum) Yes, but what is your point? only first the only Maybe people were smarter then than they are today? I don't claim to have brilliant ideas, only ideas born from straight thinking which questions certain claims from emperors who roam the streets naked. My ideas are difficult to understand, but I think that's due at least as much to the inability of many to react well to change as they are difficult to explain. At what point do you say, "let us suppose he is right about that, how can it be defended?", instead of the usual, "you must conform to my idea of what a good idea is or you will fail to impress anyone with your wild ramblings." For anyone to believe that good ideas must be shown by or must contain math constructs is conformist to the nth degree simply because and especially since math is the way of Theoretical Physics and not empirical research. AE taught us that math can be manipulated toward any end, true or false, and we know that logical reasoning can also be manipulative, but many seem to forget that and they accept math as Truth and Fact when presented by those whom they admire as their mentors or teachers. Think how many trudged off with their heads bowed when their hero AE admitted his errors. What made them think he could do no wrong? How could they be so gullible when the word is not even in the dictionary? Straight thinkers will take an idea - any idea - and review it to the end of the trail it leads to which ends at either that point where it can be deemed invalid or that point where it must be defended against detractors. TomGee |
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#10
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| Geraldine Hobba wrote: news:1109718918.946975.264110@o13g2000cwo.googlegr oups.com... physical SNIP a are Yes, Bill, if you had read the previous posts in this thread you would have better known what has already been discussed. To come in midway and rehash stuff already covered shows a selfish side not many would want to show in public. that naturally results form Noethers famous theorem - it is the conserved charge related to time symmetry. It conservation is logically equivalent to time invariance of the lagrangian. This issue cares not where it naturally resulted from, Hobbit, nor what it is related to nor logically equivalent to whatever of whatever. Energy has already been defined as a quantity in this thread. force No, you're wrong again, Bill, force has already been defined previous to your entrance into this thread as a physical influence that tends to change the position of an object with mass, equal to the rate of change in momentum of the object. inertial frame which is logically equivalent to Newton's famous third law. Yes, and so what? SNIP force. directional Therefore, inertia is a property and as a property it cannot also be an exercise of the power of the energy which is inherent in the said body. SNIP non-relevant statements property cannot Then why do you do it? idea contain be [Only registered users see links. ] That may be the opposite of what he thought, but it is what he taught the world when he used math to prove his static universe. Also, you imply that the quote below is from AE hisself - shame shame shame! It is only an opinion by others who are motivated to publish or perish. and physical thinking which goes a long way toward explaining why so few mathematicians have made important contributions to physics in the 20th century. Pure mathematicians do not think about the equations of physics in the same way as a physicist does. They are concerned only with the structure of the equations and the formal rules for manipulating them. That is precisely the definition of the science of Theoretical Physics which I gave previously in this thread, which you obviously did not read. or processes; they are only partial representations of the physicists' knowledge, so to improve a representation they may alter the equations in ways that violate mathematical rules. Both Einstein and Heisenberg were masters at this. So how is the above exactly opposite to what I said? Einstein was developing his general relativity theory, the mathematician Hilbert expressed the opinion that Einstein was mathematically naive. I have heard a similar opinion about Heisenberg expressed by one of his students in later years. Mathematics played an essential role in Einstein's thinking, but, as mathematical physics goes, the mathematics in all his great papers is comparatively simple. His forte was in analyzing the physical meaning of the mathematics. Indeed, such analysis is generally characteristic of the best work in theoretical physics. I have heard the Nobel laureate Richard Feynman, himself a true mathematical virtuoso, express this opinion forcefully, asserting that the value of a paper on theoretical physics is inversely proportional to the density of mathematics in it.' Again, isn't that what I was saying? that makes a great physicst. What is happening was also expressed elequontly by Cleick in a famous remark about Feynman, Eisntein and Landau [Only registered users see links. ] twenty-three ... there was no physicist on earth who could match his exuberant command over the native materials of theoretical science. It was not just a facility at mathematics (though it had become clear ... that the mathematical machinery emerging from the Wheeler-Feynman collaboration was beyond Wheeler's own ability). Feynman seemed to possess a frightening ease with the substance behind the equations, like Einstein at the same age, like the Soviet physicist Lev Landau - but few others.' This is apparently the opposite of what I said, but it's just opinion that Wheeler was limited while Feynman was beyond greatness with his overwhelming math and substance. So why did he need Wheeler if he was so great? Opinions are subjective beyond belief when they voice admiration for someone the author considers god-like. that makes a great physicist - not the arbitrary manipulation of mathematics. Ah Ha Ha! That is pure opinion from you using someone else's words! How crass of you. admitted his errors. All of them. Every single one of them, none of which are specifically germane to this discussion. "Gullible" is the word I referred to which does not appear in dictionaries nor in reference works. inclination to - understand something before criticizing it. But that is exactly what you did when you wrote the above without bothering to read what had been discussed before you entered the fray! You barged right in with the utmost misunderstanding of the issues and you proceeded to criticize everything of which you had no undertanding! One thing I can always count on from you, Hobble, is a good laugh. TomGee |
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