Cap'n Refsmmat Posted December 24, 2011 Posted December 24, 2011 That still leaves us with the challenge, are length contraction and time dilation based on idealism (reality depends on observation) ? If so, there is no ‘real world’ independent of observation. Realism claims that there is. My claim is that the at rest frame yields the most accurate description of that world, be it shapes of objects (diameters) or distances between them (Earth to Sun or to Alph Centauri.) If measurements from other frames are "inaccurate", what consequences come from this inaccuracy? Are there implications for predictions made based on these "inaccurate" measurements?
ydoaPs Posted December 24, 2011 Posted December 24, 2011 If measurements from other frames are "inaccurate", what consequences come from this inaccuracy? Are there implications for predictions made based on these "inaccurate" measurements? How do we know which frame is the accurate one?
owl Posted December 24, 2011 Author Posted December 24, 2011 Ps; for the record regarding Swansont's false assertion: For the newcomers: owl has admitted to not being a scientist. I have frequently "admitted" to being a non- mathematician. I have always claimed to be an *amateur scientist.* That literally means 'one who loves science' but not a professional. Apparently Swansont equates being a scientist to being a mathematician and thinks that love of science doesn't matter without the credentials and the profession. No need for an apology. We passed beyond that kind of civility long ago.
ydoaPs Posted December 24, 2011 Posted December 24, 2011 Ps; for the record regarding Swansont's false assertion: I have frequently "admitted" to being a non- mathematician. I have always claimed to be an *amateur scientist.* That literally means 'one who loves science' but not a professional. Apparently Swansont equates being a scientist to being a mathematician and thinks that love of science doesn't matter without the credentials and the profession. No need for an apology. We passed beyond that kind of civility long ago. I took the liberty of properly utilizing the quote function for you so that swansont knows you took a shot at him. For the newcomers: owl has admitted to not being a scientist. Now, back to the question you refuse to answer: How do you know which frame is the 'correct' one? That still leaves us with the challenge, are length contraction and time dilation based on idealism (reality depends on observation) ?Nope. My claim is that the at rest frame yields the most accurate description of that world, be it shapes of objects (diameters) or distances between them (Earth to Sun or to Alph Centauri.) Which rest frame? In my example you predictably ignored, both frames A and B were rest frames. Try to understand the difference between these two statements: A: Earth’s shape depends on the frame of reference from which it is viewed. B: The appearance of Earth’s shape depends on the frame of reference from which it is viewed. I do not dispute B. I dispute A. I dispute the claims that it either changes shape or that we can not know its shape. Another point in my last post you completely ignored is relevant here. Length contraction is a PREDICTION. We didn't see it coming. It was predicted that space changes magnitude. It would be an incredible coincidence for space to appear to contract the exact amount that space was predicted to actually differ. The point I raised above is still rather pertinent here; which frame is the correct one? How do you know? You say the rest frame, but with respect to what is the frame at rest? Another pertinent point from my last post you completely ignored: If length contraction is only apparent, how can we see light 'bend' around stars? My answer does not require playing your game, because in the real world (asserted as a realist as the basis of my argument), ‘A’ above is false and ‘B’ above is true. The variability of *appearances* is already granted.Oh, but it really does. You see, as I have pointed out above, both frames A and B in my example are rest frames. Which one gives the "correct" answer? They just “tick”, and that slows down at high speeds.Yet the tick varies consistently among all clocks, even when the 'clock' is the halflife of a particle in an accelerator. This, again, is a point you completely ignored. Basically, you didn't really respond to my post at all and every one of your points remains defeated.
md65536 Posted December 24, 2011 Posted December 24, 2011 That still leaves us with the challenge, are length contraction and time dilation based on idealism (reality depends on observation) ? “What shape is Earth?” (posed by realists who say it has an intrinsic/objective shape), what would you say? I still think those are wrong. They are owl-redefinitions of the words. You're saying that owl-idealism is "reality is as it is measured to be", and owl-realism is "reality conforms to an ideal that is true regardless of how it is measured". In owl-realism, the shape of the Earth is spherical, even if it isn't measured to be so, and is only "known" to be so -- it has an ideal shape within the mind. I think you have your definitions BACKWARDS. It is my most humble of opinions that anyone who accepts any of your definitions without questioning them has been made stupider for it. Perhaps if you prepend "owl-" as I am doing, as in "owl-time is event duration of physical processes", "owl-psychologist is someone with an interest in psychology" etc, it would prevent people from being confused. As I've always said, you're spreading misinformation and you continue to do it at the same garbage-spewing rate. I think that some others here don't bother to correct you on your philosophical mistakes, because they don't treat philosophy with enough respect to care whether it is presented correctly or not. But I care! Can't you see that I'm the only one giving you proper respect, you idiot? Have a merry Christmas and a happy holidays, everyone! Maybe in the new year we'll figure out the true nature of the unknowable aspects of reality! 2
swansont Posted December 24, 2011 Posted December 24, 2011 Ps; for the record regarding Swansont's false assertion: I have frequently "admitted" to being a non- mathematician. I have always claimed to be an *amateur scientist.* That literally means 'one who loves science' but not a professional. Apparently Swansont equates being a scientist to being a mathematician and thinks that love of science doesn't matter without the credentials and the profession. No need for an apology. We passed beyond that kind of civility long ago. You claimed expertise. How convenient to focus on this detail rather than address the larger picture. I love certain sports. It does not mean I am particularly good at them, certainly as compared to a professional. By all means, focus on this comment rather than the discussion at large. Please refer to the recently discussed paper on science's “bad habits,” one of which is reifying time. I have beat it to death already in many threads. Clocks do not “detect” something mysterious called time and then measure “it.” They just “tick”, and that slows down at high speeds. I am not here theorizing about why high speed (or higher gravity fields) makes clocks tick more slowly. You claim relativity is false. Yet you have nothing to fall back on to explain the behavior that relativity predicts. Doesn't realism demand that clocks tick at their inherent rate? 3
owl Posted December 25, 2011 Author Posted December 25, 2011 YdoaPs: Now, back to the question you refuse to answer: How do you know which frame is the'correct' one? I haven’t refused to answer. You have refused to hear. In the case of Earth’s shape, or any other shape or distances between objects, the best option is as close as you can get, meaning the at-rest-frame with the objct of observation. Your other options will introduce unknown variables like “how constant exactly from all possible frames of reference is lightspeed itself”... the supposed ultimate constant? (Just questioning, not answering. Look at light’s pseudo-mass, called “momentum.” And how can massless “particles/waves” push solar sails, the solar wind? There are unsolved mysteries here. Let’s not pretend that we know all about light. We know its velocity. We don’t know how it pushes on things (sails, laser gun recoil, the box of mirrors.) We don’t know how mass pulls on it, though we know that it does. (Or, “curves space”... another option.) Just a little ‘christmas eve philosophy.’ Off to the family gathering. A “process” suggestion: Let’s keep it honest first and civil if possible. All these personal attacks do not serve our mutual interest in science.
tar Posted December 25, 2011 Posted December 25, 2011 TAR: I made no assertion about the North Pole being the “top of Earth.” “Above” Earth in both cases is sufficient to make the point, which was about the direction of its revolution on its axis, not about its orbit. But you could apply the same argument from “above the sun” on either side of the plane of the ecliptic. It would not change the direction of Earth’s orbit. This is a silly diversion. Earth’s spin and orbit do not need labels relative to observational perspective like clockwise from here, counterclockwise from there. Point is, the dance (spin and orbit) in the real world is as it is regardless of our perspective and which “wise” we use to describe it metaphorically relative to an analog clock. Owl, You are blowing me off as a diversion, and proving you don't "get" my point at the same time. In which direction, to you think the Earth is "really" orbiting the Sun ? Clockwise or Counter-Clockwise? Would your answer be the same or different, if you looked at the Solar system from below? I would like the Owl description of what an Owl Idealist would say, an Owl description of what an Owl Realist would say, and your description of the truth of the matter. I think that would clear a few things up, around here. For me, at least. Regards, TAR2 P.S. I am guessing you never bothered looking at the Solar System from below. Perhaps if you would do that, you would see that the Earth rotates and revolves around the Sun in a clockwise manner. And if you then consider how I could possibly know this is true, even though I have NEVER BEEN in space looking at the Solar System, from any vantage point, you might, (and I say that with hope but very little of it), understand what people on this thread, much smarter than me, have been trying to point out to you.
ydoaPs Posted December 25, 2011 Posted December 25, 2011 YdoaPs: I haven’t refused to answer. You have refused to hear. In the case of Earth’s shape, or any other shape or distances between objects, the best option is as close as you can get, meaning the at-rest-frame with the objct of observation. Your other options will introduce unknown variables like “how constant exactly from all possible frames of reference is lightspeed itself”... the supposed ultimate constant? (Just questioning, not answering. Look at light’s pseudo-mass, called “momentum.” And how can massless “particles/waves” push solar sails, the solar wind? There are unsolved mysteries here. Let’s not pretend that we know all about light. We know its velocity. We don’t know how it pushes on things (sails, laser gun recoil, the box of mirrors.) We don’t know how mass pulls on it, though we know that it does. (Or, “curves space”... another option.) Just a little ‘christmas eve philosophy.’ Off to the family gathering. A “process” suggestion: Let’s keep it honest first and civil if possible. All these personal attacks do not serve our mutual interest in science. Should this measurement be taken from orbit, the surface, or subsurface? Each will give different values. Which is the "correct"?
A Tripolation Posted December 25, 2011 Posted December 25, 2011 I think Schrodinger's point was actually to illustrate the absurdity of the Copenhagen interpretation. But, at least according to wikipedia, the Geiger counter in the box would serve as an observer collapsing the wave function so that the cat is definitively dead or alive before the box is opened. Does it matter? The matrix mechanics of quantum is mathematically equivalent to wave theory. And, yes, you have recognized the fallacy that Schrodinger introduced into his thought experiment. The idea is now used to simplify the very complicated, and often erroneously explained, concept of quantum superposition. Owl was discrediting it. He is wrong.
tar Posted December 25, 2011 Posted December 25, 2011 (edited) Owl, People don't say the Earth is revolving around the Sun in a counter clockwise direction. They say the Earth is revolving around the Sun in a Counter-clockwise direction when viewed from Polaris. The description is observer dependent. But as soon as you know this fact you automatically know that an equally valid description is, the Earth is revolving around the Sun in a Clockwise direction when viewed from an area of space that the South Pole is pointing toward. And this knowledge is based on the solid belief that the Earth indeed is revolving around the Earth in only one direction. And knowing this, you can deduce what it will look like, from ANY perspective. And you can do this, by picking up a globe, spinning it West to East, verifying what that looks like from the top (Counter-clockwise rotation), then lift it up over your head while it is still spinning in the same direction, and see that it is spinning in a clockwise direction. You can safely say that if the globe acts this way, behaves this way, then so must the Earth, because you are investigating the properties of a spinning sphere, and both the Earth, and the globe, are in this case, representative of each other in enough ways to know what MUST be the case, in the spinning Earth's case, if it is the case in the spinning Globe's case. Equations are like globes. They allow you to build a model and play with it. Manipulating the model, to see how it behaves. And if the model is close enough to the thing you are modeling, you can actually experiment on the model, see what properties it has, that would also have to be the case for the real thing if your model was accurate in enough ways, and form a "prediction" of how the real thing would have to behave, should your model be correct enough. Idealism is in there. Realism is in there. We make analogies, out of analogies, and determine what is real from our results. We match what we think, against what actually is the case. Your whole argument is "Well your theory must be wrong, your globe is made of cardboard and really small, I happen to know that the Earth is much bigger than that, and made of a whole bunch of stuff in addition to cardboard." "You can't tell ME the Earth is made of cardboard." To which the thread is saying back to you "Well yes, we know the globe is made of cardboard and the Earth is not only cardboard, but it behaves as the Earth behaves in this particular way". "We tested it out with real world experiments and observations, and so far all our tests match the predictions of our theory". So you say "Well your theory must be wrong, your globe is made of cardboard and really small, I happen to know that the Earth is much bigger than that, and made of a whole bunch of stuff in addition to cardboard." "You can't tell ME the Earth is made of cardboard." Sigh.... Disclaimer. Quotes in this post are from TAR2's imaginary Owl they are not "real". They were never uttered by Owl or the thread responders. Edited December 25, 2011 by tar 1
swansont Posted December 25, 2011 Posted December 25, 2011 (Just questioning, not answering. Look at light’s pseudo-mass, called “momentum.” And how can massless “particles/waves” push solar sails, the solar wind? There are unsolved mysteries here. Let’s not pretend that we know all about light. We know its velocity. We don’t know how it pushes on things (sails, laser gun recoil, the box of mirrors.) We don’t know how mass pulls on it, though we know that it does. (Or, “curves space”... another option.) But we know that light does have momentum — this is predicted by special relativity. The momentum of a massless particle is given by E/c, which is exactly what it is measured to be in several different kinds of experiments. Science doesn't explain the underlying "why" because that is not what science does; no matter how deep an explanation goes there will always be another one below it that is unexplained. That there are unsolved mysteries in no way diminishes the mysteries that science has solved. By the same token, we don't know why massive objects push on things either, in exactly the same way we don't know how light does it. 2
Iggy Posted December 26, 2011 Posted December 26, 2011 Does it matter? The matrix mechanics of quantum is mathematically equivalent to wave theory. And, yes, you have recognized the fallacy that Schrodinger introduced into his thought experiment. The idea is now used to simplify the very complicated, and often erroneously explained, concept of quantum superposition. Owl was discrediting it. He is wrong. No, I don't suppose the bit abut the geiger counter acting as the observer matters, but the other bit, most definitely. Owl discredits spacetime in the same way he is trying to discredit superposition. He says, relativity posits a curved medium which doesn't, in fact, exist. What a headache everybody would be saved had someone been there at the start to say "spacetime is a way to organize events... not a real physical thing". The Copenhagen interpretation says that the state of the system described by the wave function means only what we can say about the system. It isn't that the cat has to be alive and dead for QM to work any more than spacetime has to be a real curved physical medium for relativity to work. It's interpretation dependent. It is enough, and it's consistent with the Copenhagen interpretation, just to say that our knowledge of the state of the cat at that time is equally consistent with both. If you deny Owl the opportunity to reify the wave function then his declaration that every cat is either alive or dead doesn't discredit anything.
owl Posted December 27, 2011 Author Posted December 27, 2011 (edited) You claimed expertise. How convenient to focus on this detail rather than address the larger picture. I'll just start at the top (about claiming expertise) and work down to catch up here. I was hired by a university (to remain anonymous because I place a very high value on anonymity and confidentiality)... to teach a course entitled "Logic and the Scientific Method" in the philosophy department. I did not have a doctorate, but neither did the dean/head of the philosophy department, but he was brilliant, and so was I. They say "size doesn't matter"... or IQ scores, but they do in the context of ones academic work...essays, papers and GPA in higher education. I had studied science since I was old enough to be interested... at quite an early age. I had studied philosophy and logic in college and knew the principles of "the scientific method." Long story short, I taught the class, and it was both popular and cited for merit by the dean, who was my personal academic adviser. So, yes, I claimed expertise in that specific subject. I also taught 'special courses' (for the gifted, not the retarded, just to be clear) in the psychology department. (Yes, my adviser was in the philosophy dept, tho my degrees were in the psychology dept. If this is confusing, that is not my problem.) Next point: I love certain sports. It does not mean I am particularly good at them, certainly as compared to a professional. By all means, focus on this comment rather than the discussion at large. I will get to "the discussion at large"... maybe later. I don't think your love of sports without expertise is relevant to my love of science with the expertise I had to teach the course. You claim relativity is false. Yet you have nothing to fall back on to explain the behavior that relativity predicts. Doesn't realism demand that clocks tick at their inherent rate? I have probably said this over a hundred times in this forum, but here it is again for those who will not hear it: I do not claim relativity is false. I've praised its relevance to GPS systems over and over... always ignored by Swansont. I claim that "length contraction," "time dilation" and spacetime (as a malleable medium) is false. If it bends, curves, expands (space specifically) has shape and guides objects in curved paths, 'whatever it is', it is presented by GR as a malleable medium. ("Mass curves spacetime.") If it is just an abstract coordinate system, then the curvature is a mental construct, not part of the "real world" which physics describes. Another hundred or so times I have said that time is *duration* of physical processes. (*Elapsed time, whether "clocked" or not.) Clocks are built to be very steady 'ticking' devises, not time detectors/measurers. Some here know the difference and some don't. (You, Swansont, don't.) Clocks don't "measure" anything. They just 'tick.' They tick more slowly at high speeds and in high gravity fields. I don't know 'why' and neither does relativity theory. Back to continue as "time permits.' Owl, You are blowing me off as a diversion, and proving you don't "get" my point at the same time. In which direction, to you think the Earth is "really" orbiting the Sun ? Clockwise or Counter-Clockwise? *I answered that already.* It doesn't matter how any observer looks at it. The real Earth orbits (and has always orbited) the real Sun in the same direction since the solar system came together from natural gravitational processes. Would your answer be the same or different, if you looked at the Solar system from below? Ditto *...* above. I said that from one side of the ecliptic (look it up if unfamiliar) the orbit would be clock-wise and counter-clockwise from the other side of the ecliptic, as seen from 'above the sun' on either side... no "top" or "bottom" implied. Just above the sphere in whatever direction from its center... as with 'above the Earth' in whatever orbit or above whatever surface location. I would like the Owl description of what an Owl Idealist would say, an Owl description of what an Owl Realist would say, and your description of the truth of the matter. I think that would clear a few things up, around here. For me, at least. You, like others want to make this personal. It is not. I speak as a realist against idealism as a shared philosophy of science among many like minded whom I have quoted. There are no "Owl Idealists." Owl thinks that idealists are idiots. They think that the shape of things and the distances between them (and the length of a meter rod) all vary ("Length is not invariant!") with the frame of reference from which they are observed. They claim that the invariance of 'c' proves that everything else varies with frame of reference. Any realist will say that Earth's shape does not vary with observation. Same for the distance to the Sun or to other stars. P.S. I am guessing you never bothered looking at the Solar System from below. Perhaps if you would do that, you would see that the Earth rotates and revolves around the Sun in a clockwise manner. And if you then consider how I could possibly know this is true, even though I have NEVER BEEN in space looking at the Solar System, from any vantage point, you might, (and I say that with hope but very little of it), understand what people on this thread, much smarter than me, have been trying to point out to you. See clarification 'above' on direction of orbit and previously on direction of Earth's rotation. Neither changes with from where it is observed. The latter obviously (from polar orbit satellite observation) rotates counter-clockwise as seen from 'above' the North Pole and clockwise as seen from above the South Pole. The discouraging thing for me is that i said all this before and you simply did not comprehend it. I will soon quit replying to your posts if you still don't understand what I repeated above. Edited December 27, 2011 by owl -1
Schrödinger's hat Posted December 27, 2011 Posted December 27, 2011 *I answered that already.* It doesn't matter how any observer looks at it. The real Earth orbits (and has always orbited) the real Sun in the same direction since the solar system came together from natural gravitational processes. Ditto *...* above. I said that from one side of the ecliptic (look it up if unfamiliar) the orbit would be clock-wise and counter-clockwise from the other side of the ecliptic, as seen from 'above the sun' on either side... no "top" or "bottom" implied. Just above the sphere in whatever direction from its center... as with 'above the Earth' in whatever orbit or above whatever surface location. So you are saying that the direction of the earth's orbit changes arbitrarily depending on 'frame of reference'? Realism states that it must either be clockwise or anti-clockwise. Hundreds of years of observations have measured earth to be orbiting anti-clockwise. So which is it? Has earth always been orbiting anti-clockwise or do you subscribe to subjective idealism? 1
swansont Posted December 27, 2011 Posted December 27, 2011 "I taught a class" carries about the same weight as "I wrote a book". Neither demonstrates any actual expertise. I've also taught (and administrated) enough to know that popularity does not necessarily equate with expertise. I've seen good teachers who were popular and I've seen poor teachers who were popular. I have probably said this over a hundred times in this forum, but here it is again for those who will not hear it: I do not claim relativity is false. I've praised its relevance to GPS systems over and over... always ignored by Swansont. I claim that "length contraction," "time dilation" and spacetime (as a malleable medium) is false. If it bends, curves, expands (space specifically) has shape and guides objects in curved paths, 'whatever it is', it is presented by GR as a malleable medium. ("Mass curves spacetime.") If it is just an abstract coordinate system, then the curvature is a mental construct, not part of the "real world" which physics describes. If you claim length contraction and time dilation to be false, you claim relativity is false. You can't have it both ways. You have no explanation for why clocks tick differently when traveling at speed or in a different gravitational potential. GPS apparently runs by magic. GR and SR do not claim there is a malleable medium. That's YOUR claim. You base this claim, apparently, on the vocabulary and descriptions of it, which are used because we are forced to discuss this in an imprecise language, which means we use analogies and descriptions. I'm sorry you don't get this, but it's like someone getting so hung up on grammar that they completely ignore the concept that a passage is conveying. As ydoaPs has already explained, the only information we have available to us is that of how things behave. GR gives us a method of knowing the kinematic behavior of objects, by using geometry. It's an abstraction and it's mathematical. The way we describe this abstraction is with some analogies and descriptive language. Another hundred or so times I have said that time is *duration* of physical processes. (*Elapsed time, whether "clocked" or not.) Clocks are built to be very steady 'ticking' devises, not time detectors/measurers. Some here know the difference and some don't. (You, Swansont, don't.) Clocks don't "measure" anything. They just 'tick.' They tick more slowly at high speeds and in high gravity fields. I don't know 'why' and neither does relativity theory. Isn't a "tick" a physical process that has a duration? I've never seen the inconsistency that you appear to see. You have a repeating process in a clock; that's how they work. With your definition of time, clocks still measure time. However, observers in different frames, using the same identical processes (i.e. identical clocks), will disagree on the duration of some other event. This has been experimentally confirmed. (BTW, I never get tired of being told how much I don't understand about clocks and time on SFN) 2
owl Posted December 27, 2011 Author Posted December 27, 2011 Cap ‘n R: If measurements from other frames are "inaccurate", what consequences come from this inaccuracy? Are there implications for predictions made based on these "inaccurate"measurements? Earth science textbooks saying that its shape varies from quite flattened to almost spherical... or that it can not be known since all possible frames of reference are equally accurate... would be one “consequence.” Ydoaps: Now, back to the question you refuse to answer: How do you know which frame is the 'correct' one? Applying reason, we find the frame closest to at rest with objects observed, which will reduce unknown variables (like whizzing by at near ‘c’) to a minimum. YoadaPs: Should this measurement be taken from orbit, the surface, or subsurface? Each will give different values. Which is the "correct"? I think that giant Earth- sized calipers “sizing it up” from a few million opposite points on the surface would be best.... or holes drilled through its diameter and lengths measured by laser. But precise measurements taken from various orbits (same altitude in all cases) will have to do meanwhile. Schrodinger’s hat: So you are saying that the direction of the earth's orbit changes arbitrarily depending on 'frame of reference'? Realism states that it must either be clockwise or anti-clockwise. No. Just the opposite, as repeated already several times in answer to TAR above. Hundreds of years of observations have measured earth to be orbiting anti-clockwise.So which is it? Has earth always been orbiting anti-clockwise or do you subscribe to subjective idealism? Yet again, the direction of Earth’s orbit around the Sun does not and never has changed. How we would see it from which perspective is the argument from idealism: that reality is determined by observation from different frames of reference. (“clockwise from here; counter-clockwise from there.”) Me, starting with first repetition above: *I answered that already.* It doesn't matter how any observer looks at it. The real Earth orbits (and has always orbited) the real Sun in the same direction since the solar system came together from natural gravitational processes. Ditto *...* above. I said that from one side of the ecliptic (look it up if unfamiliar) the orbit would be clock-wise and counter-clockwise from the other side of the ecliptic, as seen from 'above the sun' on either side... no "top" or "bottom" implied. Any realist will say that Earth's shape does not vary with observation. Same for the distance to the Sun or to other stars. See clarification 'above' on direction of orbit and previously on direction of Earth's rotation. Neither changes with from where it is observed. The latter obviously (from polar orbit satellite observation) rotates counter-clockwise as seen from 'above' the North Pole and clockwise as seen from above the South Pole. Italics added. The 'as seen from' perspective does not mean that the direction of rotation (or orbit) changes, but that the perspective changes. So this is the third repetition of my answer to TAR’s and now your question.
tar Posted December 27, 2011 Posted December 27, 2011 *I answered that already.* It doesn't matter how any observer looks at it. The real Earth orbits (and has always orbited) the real Sun in the same direction since the solar system came together from natural gravitational processes. Ditto *...* above. I said that from one side of the ecliptic (look it up if unfamiliar) the orbit would be clock-wise and counter-clockwise from the other side of the ecliptic, as seen from 'above the sun' on either side... no "top" or "bottom" implied. Just above the sphere in whatever direction from its center... as with 'above the Earth' in whatever orbit or above whatever surface location. You, like others want to make this personal. It is not. I speak as a realist against idealism as a shared philosophy of science among many like minded whom I have quoted. There are no "Owl Idealists." Owl thinks that idealists are idiots. They think that the shape of things and the distances between them (and the length of a meter rod) all vary ("Length is not invariant!") with the frame of reference from which they are observed. They claim that the invariance of 'c' proves that everything else varies with frame of reference. Any realist will say that Earth's shape does not vary with observation. Same for the distance to the Sun or to other stars. See clarification 'above' on direction of orbit and previously on direction of Earth's rotation. Neither changes with from where it is observed. The latter obviously (from polar orbit satellite observation) rotates counter-clockwise as seen from 'above' the North Pole and clockwise as seen from above the South Pole. The discouraging thing for me is that i said all this before and you simply did not comprehend it. I will soon quit replying to your posts if you still don't understand what I repeated above. Owl, How do you know I wasn't one of your students? Maybe I thought you taught me wrong. Or maybe I listened to every word you said, and am thinking for myself about the consequences and agreeing with SwansonT on the basis of overwhelming real evidence. And you didn't answer my questions. How would an Owl realist describe the direction of motion of the Earth around its axis? How would an Owl idealist describe the direction of motion of the Earth around its axis? How would Owl describe the direction of motion of the Earth around its axis? And since the idealist answer, must be idiodic, and the Owl answer must be real, be sure that the idealist answer is both replete with observer dependent terms, and wrong, and the Owl answer uses no observer dependent terms, ( or actual observations,) and is correct. And remember, I am asking only for a description of the rotation of the Earth about its axis, we can leave SR and GR out of it for these purposes. I am trying to understand what you mean. (and think you are confused about something). Just want you to lay it directly on the table, so we can take a look at your "view". How is the Earth "really" rotating? Regards, TAR2
Cap'n Refsmmat Posted December 27, 2011 Posted December 27, 2011 Earth science textbooks saying that its shape varies from quite flattened to almost spherical... or that it can not be known since all possible frames of reference are equally accurate... would be one “consequence.” Would this have any consequences for making scientific predictions about the results of experiments and observations? Would there be experimental predictions made inaccurate because Earth was measured from the "wrong" frame? Applying reason, we find the frame closest to at rest with objects observed, which will reduce unknown variables (like whizzing by at near ‘c’) to a minimum. That's not an "unknown" variable; it's a precisely known variable, with known consequences. 1
owl Posted December 27, 2011 Author Posted December 27, 2011 "I taught a class" carries about the same weight as "I wrote a book". Neither demonstrates any actual expertise. I've also taught (and administrated) enough to know that popularity does not necessarily equate with expertise. I've seen good teachers who were popular and I've seen poor teachers who were popular.[/Quote] You challenged my claim to expertise on a specific subject. I clarified the course I taught and that it was cited for merit by the dean, the authority in that case on its merit as an introduction to "Logic and the Scientific Method"in a college level course. I also mentioned a brief history of my interest in and study of science and the logic part of it. If you claim length contraction and time dilation to be false, you claim relativity is false. You can't have it both ways. You have no explanation for why clocks tick differently when traveling at speed or in a different gravitational potential. GPS apparently runs by magic. Not true. Why clocks slow down in above circumstances remains an unknown. Claiming that shapes and lengths vary with observation is idealism, philosophically speaking. Realism claims that things might appear different 'as seen from' different frames, but that they don't actually change... like Earth getting flatter or closer to the sun... or a solid meter rod shrinking, as it might appear from extreme frames. Claiming that "time slows down" reifys time, while simply acknowledging that clocks tick more slowly (as above) is direct observation without reification of time. GR and SR do not claim there is a malleable medium. That's YOUR claim. You base this claim, apparently, on the vocabulary and descriptions of it, which are used because we are forced to discuss this in an imprecise language, which means we use analogies and descriptions. I'm sorry you don't get this, but it's like someone getting so hung up on grammar that they completely ignore the concept that a passage is conveying. Every time introductory GR "explains" that "mass curves spacetime", the latter is falsely reified, and students will nod and repeat it on tests. If it were just called Factor X in the equations, science would become honest and the error of reification would be eliminated. Sorry the point is lost on you. Then quantum mechanics could call its version of gravity "Factor Y" and eliminate the search for the elusive and metaphysical "graviton." Of course, in neither case is there an explanation of how mass attracts mass... or bends light... at a distance. Isn't a "tick" a physical process that has a duration? I've never seen the inconsistency that you appear to see. You have a repeating process in a clock; that's how they work. With your definition of time, clocks still measure time. However, observers in different frames, using the same identical processes (i.e. identical clocks), will disagree on the duration of some other event. This has been experimentally confirmed. Yes, exactly... " a 'tick' (is) a physical process that has a duration? But then you say, "With your definition of time, clocks still measure time." No. They 'tick' while natural physical processes observed happen. When the observed focus on a "duration of a physical process" is over, we can say how many 'ticks' coincided with the process observed. So many ticks for a full rotation of Earth, for instance. But the clocks in orbit will record fewer ticks than those on the ground... and those at different altitudes (gravity fields) will also vary during one Earth rotation. So relativity does an excellent job of adjusting for all those differences to make good sense and achieve precision of location (for GPS units) in all cases. All that does not require that "time dilates." (BTW, I never get tired of being told how much I don't understand about clocks and time on SFN) Good.I hope you enjoyed the above reiteration. Would this have any consequences for making scientific predictions about the results of experiments and observations? Would there be experimental predictions made inaccurate because Earth was measured from the "wrong" frame?[/Quote] I'll use the interstellar version of length contraction to answer... same principle. If planning for an exploratory trip to Alpha Centauri is based on the distance (according to length contraction) being very much shorter than 4.3 lightyears, it seems to me that the rocket scientists would underestimate the amount of fuel required. Re Earth: Certainly no air travel calculations for required jet fuel to circumnavigate the globe will be based on measurements of Earth's equatorial diameter from the old near 'c' fly-by. That's not an "unknown" variable; it's a precisely known variable, with known consequences. To my point... Do you or do you not think that Earth has an intrinsic/objective shape independent of observational frame of reference? If you do, then what frame would you "prefer" from which to measure it and describe its "true shape?"
Cap'n Refsmmat Posted December 27, 2011 Posted December 27, 2011 I'll use the interstellar version of length contraction to answer... same principle.If planning for an exploratory trip to Alpha Centauri is based on the distance (according to length contraction) being very much shorter than 4.3 lightyears, it seems to me that the rocket scientists would underestimate the amount of fuel required. Relativistic kinematics provides methods to compute the time the rockets will need to fire, and so on. Classical mechanics will give you an entirely incorrect answer if you travel at high speed, because it incorrectly assumes that momentum increases linearly with velocity -- and so it will assume your rockets will be able to accelerate you to a much higher speed than actually possible. (This phenomenon has been seen and confirmed in numerous particle accelerator experiments, with subatomic particles and heavy atoms.) Relativity predicts a consistent view of the world in different reference frames -- that is, there are not contradictions that arise because different reference frames see events differently. There won't be one reference frame where Fred can make it to Jupiter and another where he can't. The mathematics works out to ensure consistency. So why should we call one measurement "inaccurate" if I can make incredibly precise predictions based off it, just like I can with the "accurate" measurement? Re Earth: Certainly no air travel calculations for required jet fuel to circumnavigate the globe will be based on measurements of Earth's equatorial diameter from the old near 'c' fly-by. Naturally. You don't use measurements from a completely different reference frame to do your calculations. To my point...Do you or do you not think that Earth has an intrinsic/objective shape independent of observational frame of reference? I do not think the Earth has an intrinsic three-dimensional shape independent of frame of reference, no.
tar Posted December 27, 2011 Posted December 27, 2011 Owl, I guess my point is that scientist have an idea of how the universe behaves. It is based on realism, as in how it is observed to behave. You seem to think that your idea of how the universe behaves is somehow more correct, or purer. Just wondering where you are getting that "idea", if not from observations. As if, you are so smart, that you have been able to "figure it out", just by thinking about how it must be. You are sure of yourself...but don't bother to lift the globe up and look, or look at it from the plane of the elipse. From the plane, it doesn't even rotate, it goes from side to side (left to right) or if you turn it upside down, right to left. If we put "all the views together" we can have an "idea" of how it "really" is spinning. But you can not go the other way round, and figure you already know and derive anything "real" from your "idea". Scientists already know this. Owls are so wise, they know what reality is, without looking. So you have an "idea" of what must be the case. So do scientists, otherwise they couldn't do science. If you know what one direction, the Earth alway has, and continues to rotate in, please explain what that is, and how you know it to be the case. So it can be real to us, and not just a thought in your head. Regards, TAR2 1
md65536 Posted December 27, 2011 Posted December 27, 2011 Applying reason, we find the frame closest to at rest with objects observed, which will reduce unknown variables (like whizzing by at near 'c') to a minimum. If things have an intrinsic shape, do they also have an intrinsic speed? We can ignore actual speeds by measuring only from the "best" speed. Ideally, everything should be measured at rest, to reduce unknown variables. Is "at rest" the ideal speed for everything in owl-realism? It would certainly make measuring the speed of a car simplest and most accurate if it was done while the car is at rest. I'll give you that much, it would certainly simplify a lot of physics straight out of existence with this reasoning. 1
owl Posted December 27, 2011 Author Posted December 27, 2011 I do not think the Earth has an intrinsic three-dimensional shape independent of frame of reference, no. Well, there we have it, finally acknowledged! There is no 'real Earth' independent of observation according to the Cap 'n of this science forum. It all depends on how we look at it. This, for everyone's information, is a form of idealism: It's all subjective, with the caveat that subject = frame of reference here, however abstract. If "three dimensional" was an important qualifier, please explain how other "dimensions" (besides time... yada yada) are verified as accurate descriptions of 'the world', not just mental models for math without referents.... like M-theory's eleven dimensions... to which you do not, apparently subscribe. Just give me one more axis describing space, if you can, besides the well known three dimensions. If this question is confusing, please study the Kelley Ross paper on the Ontology and Cosmology of Non--Euclidean Geometry if you haven't already. (Frequently cited in support of my Euclidean based argument.) The irony of ontology is that it tries to sort out the differences between merely metaphysical concepts and what the hell they might refer to in the "real world" that science/physics/cosmology is here to describe and clarify as true knowledge about it (the 'real world.) But you continue to deny a 'real world' as if it is all in our brilliant homosapient heads! If i have this wrong about you, please explain how. 1
md65536 Posted December 28, 2011 Posted December 28, 2011 (edited) Well, there we have it, finally acknowledged! There is no 'real Earth' independent of observation according to the Cap 'n of this science forum. It all depends on how we look at it. This, for everyone's information, is a form of idealism: It's all subjective, with the caveat that subject = frame of reference here, however abstract. Yes!!!! Well done owl! You've finally done it! I think we are finally all in agreement! I can agree totally with your post so far. (I don't want to ruin it by continuing reading.) Does anyone still disagree? For everyone's information, this form of idealism is not what other philosophers would typically refer to when using the word 'idealism'. I've been a fool, doubting that these discussions would ever be resolved. But you continue to deny a 'real world' as if it is all in our brilliant homosapient heads! If i have this wrong about you, please explain how. Well I think you've mostly got it, but it doesn't matter if it's a "homosapient head" that observes the world with its eyes etc, or a photon that measures the world by hitting it, or a particle that measures the world by moving through it, etc. That is... If you accept that reality is, by definition*, as it is measured to be, then the "real world referent" is whatever is being measured, and so the behavior of everything is consistent with measurements of reality as measured by anything that interacts in reality. Then you have a philosophical understanding of the universe that is compatible with how it behaves, and is thus compatible with science. It is not idealism, because measurements can be made independent of thought or understanding. * not the only possible definition mind you. Edited December 28, 2011 by md65536
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