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From: Traveler on 27 Sep 2005 16:41 On 27 Sep 2005 13:06:41 -0700, "platopes" <platopes(a)yahoo.com> wrote: Well, I'll be darned to hell and back. Mitch has actually formulated a couple of good questions. > If motion were a series of effects, each requiring its own cause, >would a heavier object gravitate more slowly toward a large mass than a >lighter object? No. > That is, would more of this constant force be needed to move a heavier >object than a lighter one? Yes. And the faster the object moves, the greater the force, hence the greater the energy requirement. Where does all this energy come from? Answer: from the photons that comprise the aether. There's a 4-D shitload of it, to boggle the mind. In fact, it's wall-to-wall energy and we're immersed in it. Normal matter is the exception. Soon, we'll be able to harness this unlimited energy for production and propulsion. Brave new world and all that. Louis Savain Why Software Is Bad and What We Can Do to Fix It: http://www.rebelscience.org/Cosas/Reliability.htm
From: TomGee on 27 Sep 2005 16:57 Timo Nieminen wrote: > On Thu, 21 Sep 2005, TomGee wrote: > > > Timo Nieminen wrote: > > > > > > Newton says if there is no force, there is no change in the state of > > > motion. If there is no change in the state of motion, how can the object > > > stop? > > > > > No, Newton does not say that. That's what they told us he said, but > > it's a lie. > > How can you say that it's a lie, and then basically agree: > > > He said that without an external force applying to it, an > > object will move in a straight line at a uniform motion. > > Because the paraphrasing of Newton has led us to infer things he did not say. Motion is by definition, change. Motion refers to positional change in time. So even uniform motion is a constant change in the state of motion. So yes, an object with no external force acting on it will move at constant velocity. Velocity is a vector involving speed and direction and is a measure of the rate of change in position of an object. Uniform motion (speed) in a straight line (direction) in an object constitutes a constant change of its vector component of time. > > > Yes, so if there is no external force, the object will move in a straight > line in uniform motion. That means that if there is no external force, the > speed doesn't change. That means that an _external force_ is _required_ to > stop the motion. > > Yes, I agree. > > > [cut] > > That's my whole point: The translations are actually wrong in claiming > > that Newton said an isolated body continues its motion without any > > force external or internal applying to the object. > > If that's your whole point, you should learn Latin, and read the original. > If you doubt the translations, read what Newton wrote in the original > Latin. > > I found a translation at a greenlion.com site which indicates that Newton referred to an inherent force that kept a body at constant velocity. He did not say "forever", though, so I believe that was added on later by others. > > > And do read Newton's definitions. Especially his definition of force. > Read definitions III and IV, and Newton's commentary. You will notice that > Newton's "vis insita"/"Vis Inertiae" is called "inertial mass" in modern > English physics terminology. Now, "vis insita" can be translated as > "innate force", but you should be careful with that terminology since it > is not the same as "force" in modern physics. You might also happen to > notice that Newton states in his commentary that "vis insita" is the > "inertness of the mass" only, and is careful to state that "vis insita" is > _not_ a force to the body, but a "force" exerted _by_ the body to resist > and external applied force. > > Thanks for all this good info. I don't have access to Newton's works, so I am grateful to you for posting all this. Now, I agree that "vis insita" should mean "inertial mass" and that it is a force exerted by the body, or momentum, against externally applied forces. > > > Thus, in the absence of an external applied > force, the "vis insita" does not act. > > But see, here you insert your inference from what Newton actually said. If he said that, why would he refer to an inherent force that maintains a body at constant velocity when no external forces are acting on it? > > > "Vis impressa", as defined in def IV, is what is called "force" in modern > physics terminology. > > I would say that is what is called an external force, as in an impressed force, in modern physics. > > > Now, if you wish to argue that "vis inertiae" is the "internal force" that > sustains motion, (a) this is not "force" as the term is used in modern > physics, > > Yes, I can agree to that. > > > (b) it is the same as saying that "mass" is the "internal force" > that sustains motion, > > Again, I agree. I do not think Newton meant it that way. > > and (c) calling "inertia" a "force" might change the > name, but won't change the physics. Newton's statement that, in your > words: > > without an external force applying to it, an > > object will move in a straight line at a uniform motion. > still means that an external force ("vis impressa") is _required_ to stop > motion. > > I have not ever disagreed with that, but that proves nothing, anyway. And see how you yourself use "vis impressa" to mean "an external force", which supports my claim of that above. > > > And you might be interested to read Newton's commentary on def V, > containing as it does the claim that in the absence of external forces, an > object will proceed in its motion "in infinitum". > > I did not know he said that, but I'll take your word for it. I guess he did not know enough about our universe at that time to think that most likely an inherent force in an object cannot last forever. Infinity is a theoretical physics concept because it is unfalsifiable, of course. To believe in the concept is to take it on faith. You have been a great help to me in your post, and if I have made you think a little more about your position as it is opposed to mine, I am grateful for the opportunity to do that.
From: PD on 27 Sep 2005 17:20 TomGee wrote: > PD wrote: > > TomGee wrote: > > > PD wrote: > > > > > > > > And how is YOUR model falsifiable, TomGee? What is good for the goose > > > > is good for the panderer. > > > > > > > > > > > Just find a way to show that time is not a property of matter, or that > > > time does not pass inversely proportional to an object's state of > > > motion, or that space and time are interdependent, or that the s-t > > > continuum actually exists somewhere readily accessible for anyone > > > wishing to go there, and on and on and on. > > > > You are under a mistaken impression of what "falsifiability" of a > > theory means. This term, as it is used by scientists, means the ability > > to confront a prediction of a theory against experimental observation. > > If a theory makes no unique prediction that can be confronted with > > experiment, then it is not falsifiable. A theory that is not > > falsifiable is useless as a theory. > > > > > Okay, but your theory that time is not a property of matter - that you > can falsify, right? And SR's theory of time dilation - that you can > falsify against experimental observation, right? It is certainly *falsifiable*. You perhaps don't understand the distinction between *falsified* and *falsifiable*. > And AE's theory that > space and time are interdependent - that you can falsify against the > evidence that time may be dependent on space because matter is > dependent upon space but space is not dependent on time or matter and > thus AE's interdependence theory of space and time is falsified! Explain where in the above paragraph there is confrontration of a theoretical prediction against an experimental observation. (See definition of "falsifiable".) > > Your theory that time is not a property of matter has no support for it > and thus it's only opinion, while mine is extrapolated from SR's Twin > Paradox and at least one other time dilation effect experimental > observations. Two against zero = you lose. First of all, the Twin Paradox is not an experiment. Secondly, reread the definition of falsifiability. A theory must make a *unique* prediction that is confrontable with experiment. Since your theory seems to be based on the predictions of special relativity, it is not making any new, unique, falsifiable predictions. It is therefore not a useful theory. When your theory makes *new* predictions of an observable effect that can be confronted with experiment, then you've got a falsifiable theory. > > Einstein's theory of time and space interdependence is valid only in > his imaginary s-t continuum and not in our universe where that > interdependence is non-existent, yet you believe it to be true in all > cases even though that is obviously false. Obviously false? Obviously? How so? Where's the experiment that says it is not so. Provide a *single* example where that interdependence is non-existent. For example, give a single example of two events where, given two different observers in relative uniform motion, the distance between the two events is different between the two observers but the time separation between the two events is *not* different. This would demonstrate that time and space are not interdependent. > What good is falsifiability > if you only apply it to me and not to those in whom you place absolute > faith? Ahem, you apparently are not aware of hundreds of experimental tests of special relativity's predictions, any one of which could have proven SR false by demonstrating counter-behavior. > > Was his static universe theory falsifiable? The static universe is not part of his theory. The static universe is one possible solution of his theory. It turned out not to be the solution that pertains. > Was his theory that motion > is meaningful only between two bodies falsifiable? Yes indeedy, since no experiment to detect absolute motion has ever detected anything other than relative motion, despite serious attempts otherwise. > Yes, and he > contradicted himself when he also said that time and space are > dependent upon the motion of an observer, since that makes an > observer's motion also meaningful. Sorry, that made no sense. Moreover, where is the experimental counter-evidence? (See definition of falsifiability.) > > > > > > I somehow got the idea that you knew what you were talking about when > > you used that term to question the falsifiability of Louis's ether. I > > see that I was mistaken. > > > > > Yes, you were mistaken in not seeing the dripping sarcasm of my charge. > We are dealing only with effects for which we offer explanations of > Dark Matter and Energy. We are already at odds as to whether it's > matter or energy, or both. We must be ready to change our particular > views as new evidence shows up, but there is nothing wrong with > offering up our ideas about what is the cause behind the observed > effects. In fact, it's a good thing to do that because it seems every > important serendipitous event comes from the birth of a new idea. > > Closing your mind to new ideas, then, is not good, PD. Read My Lips: > NOT GOOD!! Agreed.
From: TomGee on 27 Sep 2005 17:29 Randy Poe wrote: > TomGee wrote: > > Randy Poe wrote: > > > TomGee wrote: > > > > Randy Poe wrote: > > > > > It is a model telling you how the two things called force > > > > > and momentum are related. The equation doesn't cause this > > > > > relationship, but it is a relationship which is true. > > > > > > > > > > > > > > Still, it does not tell you what you imagined it did. > > > > > > It doesn't? Not having your telepathic powers, I don't know what > > > you mean. What did I imagine it told me and why doesn't it tell > > > me that? > > > > > > > > Anticipating your questions, I already answered them in my previous > > post. > > > > > Well since I don't recall seeing anything like that, I guess > it will have to remain an eternal mystery. Such is life. > > Your memory is quite short then. > > > > > > Equation, model, > > > > math construct, whatever, it simply states what a force is equal to in > > > > this particular case. All else you imagine it tells you is just that - > > > > imaginary. It does not imply that in the sense it is a necessary > > > > condition for the equation to hold. You can infer what you will from > > > > what it says, but at best an inference is still just a guess. > > > > > > Something I deduce mathematically from the equation F = dp/dt, > > > something that can be derived in clear, unambiguous, deductive > > > steps, is not what we normally term a "guess". > > > > > When it tells you that, okay. But when it tells you all the other stuff you have claimed it tells you, that is only what you infer from what the math-deduced something tells you. > > > > > Tell you what. Why don't you ask me a question you think I can't > > > answer from F = dp/dt? > > > > > > > > No, thanks. > > OK, then you agree that this equation suffices to tell me > all I want to know about how forces affect momentum. > > No it does not. You only infer that from what it really tells you. > > > > > > > Mass can be viewed as frozen energy, > > > > > > > > > Not according to the formula; > > > > > > No. The mathematical formulas in physics are not the physics, > > > they are merely one component of it. The physics postulates > > > are what gives meaning to the symbols in those equations. > > > > > And don't the common usage of terms which are distinct at certain > > levels of research but can be used as equivalent terms at other levels > > of notation. > > What are "levels of notation"? > > That sentence seems to be missing something. It starts out as > if it was going to ask a question, but I can't fathom what > the question was going to be. > > Why did you ask it then? Now that you know what it means you have forgotten the question. I wonder what that means, psychologically, that is. > > SNIP > > > > > > > > Newton formed the equation F=ma > > No, he did not. F = ma is a special case of F = dp/dt when mass > is constant and p = mv. The time derivative of mv is ma when > mass is constant. > > Isn't that in his Law 2? Aristotle framed F = mv which Newton purportedly overthrew with his F = ma. > > > "Lex II: Mutationem motus proportionalem esse vi motrici impressae, > et fieri secundum lineam rectam qua vis illa imprimitur." > > "The CHANGE IN MOTION is proportional to the impressed force, > and is made along the straight line along which it is impressed." > > As I said earlier in the thread, Newton makes it clear in the > discussion which follows that "motus" is the product of > mass and velocity, i.e. what we now call momentum. > > So Newton here is saying that vector force is proportional > to vector change in momentum. > > > which is consistent with Galileo's work > > and in contrast to Aristotle's F=mv . He invented calculus where he > > obtained derivatives of functions one which is the equation you use > > above. Derivatives relate to velocity and speed in obtaining average > > velocity. > > I see. That's the only place derivatives are ever used. > > You are incorrect. > > No, you're the one who made that silly claim, so you're incorrect. > > > > Thus, your use of derivatives is not relevant to our > > discussion. > > If TomGee's Law was true that derivatives are only used for > speeds > > The one who writes it owns it, and so it is your law not mine. > > > and there's no such thing as the derivative of a > momentum, > > broadening out your new law, eh? > > > then perhaps you'd be right that F = dp/dt is > not relevant to the relation between force and momentum. > > You said all that, not me. Not my fault what your mind gets from the written word. Get your momma to read it and explain it for you. > > > However, TomGee's Law is ridiculously, laughably incorrect. > > Rodney's law is beyond funny, it's ludicrous. > > > > If you knew what a derivative is you would have known how > > preposterous your argument really is. > > Oh? Please, ridicule me. Tell me how preposterous my argument > really is, based on what a derivative "really is". > > I have, you just don't know it. > > > > > > Is > > > > that hyprocrisy or fickleness? > > > > > > Neither. It's making a distinction you seem unable to, between p > > > and rate of change of p. > > > > > > > > I will guess it's a combo of both because you are unable to understand > > that the topic is p and not a derivative of p. > > The QUESTION is whether F = p, and the answer is that F = dp/dt. > > Sorry, wrong answer. > > > I am glad that at last you recognize that p and dp/dt are not > the same. Therefore it can not be simultaneously true that > force is dp/dt and is p. > > False logic. dp/dt is a derivative of p so if force is a derivative of p, it must by definition also be p. > > > SNIP more irrelevant dp/dt nonsense. > > Yes, you're fond of the "irrelevant" word aren't you? > > "Irrelevant" seems to mean "Oops, he just answered a question > that I thought was impossible and turns out to be trivial. > Better abandon that line of argument." > > Sighhhh. You are such a bore.
From: Randy Poe on 27 Sep 2005 17:42
TomGee wrote: > Randy Poe wrote: > > Well since I don't recall seeing anything like that, I guess > > it will have to remain an eternal mystery. Such is life. > > > > > Your memory is quite short then. Alas, I suppose so. So since you choose not to refresh my memory of this alleged statement, I will blithely assume you never made it. End of that discussion. > > > > Something I deduce mathematically from the equation F = dp/dt, > > > > something that can be derived in clear, unambiguous, deductive > > > > steps, is not what we normally term a "guess". > > > When it tells you that, okay. But when it tells you all the other > stuff you have claimed it tells you, that is only what you infer from > what the math-deduced something tells you. I really can't figure out what the distinction between deriving stuff mathematically from F = dp/dt, and "inferring it from the math-deduced something". Again, I'm going to ask you to point out anything, ANYTHING about the time behavior of a momentum which you think is not deducible from F = dp/dt. > > > > Tell you what. Why don't you ask me a question you think I can't > > > > answer from F = dp/dt? > > > > > > > > > > > No, thanks. > > > > OK, then you agree that this equation suffices to tell me > > all I want to know about how forces affect momentum. > > > No it does not. You only infer that from what it really tells you. What does it not tell me? Ask me a question about how force affects momentum, which you think it does not answer, or stop claiming that such things exist. > > > And don't the common usage of terms which are distinct at certain > > > levels of research but can be used as equivalent terms at other levels > > > of notation. > > > > What are "levels of notation"? > > > > That sentence seems to be missing something. It starts out as > > if it was going to ask a question, but I can't fathom what > > the question was going to be. > > > > > Why did you ask it then? Ask what? This: "And don't the common usage of terms which are distinct at certain levels of research but can be used as equivalent terms at other levels of notation." Even with my woefully failing memory, I seem to remember seeing YOU ask that. If it's a question. I still can't fathom what the question might be, if it is one. > Now that you know what it means What WHAT means? Is something there supposed to have explained "levels of notation" or something else? > > > Newton formed the equation F=ma > > > > No, he did not. F = ma is a special case of F = dp/dt when mass > > is constant and p = mv. The time derivative of mv is ma when > > mass is constant. > > > > > Isn't that in his Law 2? No. I quote Law 2 below, in the original 1726 latin. > > "Lex II: Mutationem motus proportionalem esse vi motrici impressae, > > et fieri secundum lineam rectam qua vis illa imprimitur." > > > > "The CHANGE IN MOTION is proportional to the impressed force, > > and is made along the straight line along which it is impressed." > > > > As I said earlier in the thread, Newton makes it clear in the > > discussion which follows that "motus" is the product of > > mass and velocity, i.e. what we now call momentum. > > > > So Newton here is saying that vector force is proportional > > to vector change in momentum. > > > > > which is consistent with Galileo's work > > > and in contrast to Aristotle's F=mv . He invented calculus where he > > > obtained derivatives of functions one which is the equation you use > > > above. Derivatives relate to velocity and speed in obtaining average > > > velocity. > > > > I see. That's the only place derivatives are ever used. > > > > You are incorrect. > > > No, you're the one who made that silly claim, so you're incorrect. Again, the words about "derivatives relating to velocity and speed in obtaining average velocity" I could swear were yours. At any rate, it isn't true. Derivatives are used in many places, most notably for purposes of this discussion in the equation F = dp/dt. Are you going to say F = dp/dt doesn't use a derivative? > > > If you knew what a derivative is you would have known how > > > preposterous your argument really is. > > > > Oh? Please, ridicule me. Tell me how preposterous my argument > > really is, based on what a derivative "really is". > > > I have, you just don't know it. Not much of a putdown then, was it? > > The QUESTION is whether F = p, and the answer is that F = dp/dt. > > > Sorry, wrong answer. It answers the question as to whether F = p. The answer is, F is not p. > > I am glad that at last you recognize that p and dp/dt are not > > the same. Therefore it can not be simultaneously true that > > force is dp/dt and is p. > > > False logic. dp/dt is a derivative of p so if force is a derivative of > p, it must by definition also be p. Um, no. p is not its own derivative. By "definition" everything is its own derivative? Is that your new claim? How does that work? Velocity is the derivative of position. Does that make velocity "by definition" the same as position? - Randy |