|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
On Sat, 23 Dec 2006 11:09:15 -0700, Lester Zick
wrote: Intersitial Bodies and Reference Frames in SR ~v~~ Jeff Root: I get what you are arguing: The amount of contraction seen in an object at a given point in space is different for observers moving at different speeds relative to the thing being observed. And that seems self-contradictory. Not quite, Jeff. Let me show you an example: We have two interstitial bodies traveling at different velocities with overlapping geometric SR frames of reference, AF and CD which align in the following way: A--------------(C---v2------D)------v1-----------F And different MM type experiments are conducted across CD and across AF by observers in each frame of reference at the same time. But since the velocity of AF is different from the velocity of CD different contraction factors would have to apply to each. However because AF and CD overlap one another in space this cannot be. Hence both frames of reference cannot both be contracted in exactly the way needed to explain the null results of MM conducted seperately across each frame of reference at the same time on any uniform basis. Thus uniform material or geometric contraction of the type needed to explain the null results of such experiments is not possible. ~v~~ |
#2
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
On Sat, 23 Dec 2006 12:07:33 -0700, Lester Zick
wrote: On Sat, 23 Dec 2006 11:09:15 -0700, Lester Zick wrote: Intersitial Bodies and Reference Frames in SR ~v~~ Jeff Root: I get what you are arguing: The amount of contraction seen in an object at a given point in space is different for observers moving at different speeds relative to the thing being observed. And that seems self-contradictory. Not quite, Jeff. Let me show you an example: We have two interstitial bodies traveling at different velocities with overlapping geometric SR frames of reference, AF and CD which align in the following way: A--------------(C---v2------D)------v1-----------F And different MM type experiments are conducted across CD and across AF by observers in each frame of reference at the same time. But since the velocity of AF is different from the velocity of CD different contraction factors would have to apply to each. However because AF and CD overlap one another in space this cannot be. Hence both frames of reference cannot both be contracted in exactly the way needed to explain the null results of MM conducted seperately across each frame of reference at the same time on any uniform basis. Thus uniform material or geometric contraction of the type needed to explain the null results of such experiments is not possible. On 24 Dec 2006 20:57:30 -0800, "GSS" wrote: Lester Zick wrote: On 23 Dec 2006 08:50:09 -0800, "GSS" wrote: George Dishman wrote: [. . .] Not quite. What the MMX actually measures in the time difference between the arrival of the same beam-split wave front after traversing the two paths. Not quite. What the MMX actually measures is the *phase* difference between the waves after traversing the two paths. Phase difference is just 2*pi*f*t where f is the frequency and t is the time difference so they are essentially the same thing. That is on the assumption that frequency f is not influenced by the motion of the emitter or reflector of light. But we know that the thermal motion of atoms and molecules does affect the frequency of emitted light. So it is not unreasonable to expect that the frequency f could be influenced by the motion (speed) of the emitter or reflector. The alternative explanation of MMX referred below is based precisely on this dependence of f on the speed of motion of the emitter or the reflector. Gurcharn, I don't know if you're familiar with all my previous posts on this subject but this is precisely what is required to produce the anticipated positive results for MM. No, I don't know to which particular post you are refering to. AFAIK the MMX type experiments have been repeated many times and in many forms. But in each and every case the result depends on the interference phenomenon controlled by the phase difference of reflected beams of light in two perpendicular arms of the setup. Well it's controlled by the phase difference as manifested of the combination of relative velocity of light and beam frequency. Appended here is the recent message I was referring to: (On Thu, 2 Nov 2006 00:17:07 -0000, "George Dishman" wrote: "Lester Zick" wrote in message .. . On Mon, 30 Oct 2006 22:32:19 -0000, "George Dishman" wrote: "Lester Zick" wrote in message ... Yeah, look, George, maybe this was a bad idea after all. At least on this particular subject I know considerably more than you seem to think you do since I researched the subject in detail for five years both in the journal, scientific, and popular literature and understand the mechanics involved thoroughly. I can only surmise you were being somewhat economical in your descriptions because your reply mixed together parts of three quite different theories. My comments were mainly just making sure it was clear which of your comments applied to which of the theories. Most of your comments are valid but only for certain theories. The parsimony was only directed at determining the degree of interest and what direction it might lie in. That's OK, it just reminded me of the other conversation where you talked about an "inverse square velocity curve". You meant "a velocity curve derived from an inverse square gravitational force" while I took it to mean "a velocity which depends on the inverse square of the radius" so we ended up at cross purposes. Yeah, reductionist expressionism I suppose. I've always tended towards a maximum economy of expression where possible. Sometimes it costs me. My point regarding one monochromatic light source only having one frequency should be self-evident so I don't understand why you are objecting to that. But you know that's exactly the problem. Michelson went to great lengths to ensure the light was monochromatic. So we're looking for an exotic unobvious explanation.The difficulty is that if we can discount Einstein's geometric and Lorentz's physical contraction hypotheses we're only left with a couple of experimental variables, one of which could be frequency if we understood all the mechanics involved. The problem is that a change of the frequency of the source would cause a change of fringe spacing but not a shift of the zero point since both beams are taken from the single source and remain in phase at the point of splitting. Even if one beam changed frequency but the other didn't (e.g. we use two separate sources), what you get is a fringe pattern that drifts at a rate determined by the beat frequency. Granted given the single source. However Michelson-Morley used unpolarized light whereas Kennedy-Thorndike (KT) used plane polarized light. My idea is that Einstein's frequency dilation comes into play any time a light source is moving according to the relative bidirectional velocity of light normal to the direction of the beam. And the degree of dilation is governed by the bidirectional relative velocity of light along the E vector. Now the splitting mirror remains fixed with respect to the light source but does come into play because the mirror's 45 degree axis of split lies normal to the platform and in MM would have preferentially reflected and excluded sodium light from the source with polarization angles perpendicular to the axis of platform rotation. Thus MM would have effectively used predominantly plane polarized and interference fringes would have predominantly resulted from the interaction of plane polarized light just as in KT. (By the way if memory serves KT used unequal arm lengths just to demonstrate that had no effect.) Now this effect I call frequency conjugation where plane polarized light is dilated in frequency according to the bidirectional relative velocity of light along the E axis of polarization. And this is where Einstein's so called time dilation actually comes from.If you remember he never actually showed any physical mechanism for time dilation, he just posits it as a mechanically ambiguous dilation in "time". Please excuse the length and complexity of explanation but the effect is rather complex in mechanical terms but almost certainly does exist. At least I can demonstrate the effect as a composite conjugation of frequency and relative path length.I've actually done all the compound trig calculations in three dimensions and they clearly show that unless the experimental platform is traveling through space exactly normal to the path of travel, Michelson's original expectations should be and I'm certain can be realized. All that's really necessary is to use and keep the light polarized normal to the plane of the platform and along the axis of platform rotation. Then frequencies along both mutually perpendicular paths will remain constant. The experiment is just too simple not to work. I can do the former on quite solid theoretical grounds .. I don't believe you can for SR, though you might manage for Lorentz Aether, but that's another discussion. Well this theoretical explantion is really quite brief and applies equally to any form of supposedly uniform platform contraction such as would be required to cause the null effects posited either by Einstein or Lorentz. It's what I call the problem of interstitial bodies. All nominally solid bodies are composed of myriads of particles traveling at myriad different velocities and directions. In principle we could have performed MM or KT between the earth and moon and some other body at right angles to them. Then we might have simultaneously conducted an identical experiment within the spatial boundaries of the first experiment. Consequently we'd have different contraction factors applicable to common regions of space and if contraction could be true the experiment would have to succeed to some extent in one or the other and consequently as a matter of mechanical principle would have to succeed to some degree in both. No way around it. Nor would it do any good to suggest that the underlying effects of velocity can average out because any average would represent a first order effect but the supposed contraction, frequency dilation, and changes in relative path length are all second order effects. I think you can see why the conjugate frequency dilation effect I describe above becomes essential to any conceivable mechanical explanation for the null results of MM. It's just that any uniform path length contraction of the type required to explain the null results of relative motion studies like MM is physically impossible. .. so either Michelson's expectations should be realized or we're looking for an exotic explanation (by which I mean exotic effect in the physical sense). Even Michelson himself once remarked that perhaps we don't know quite enough about the physics involved to do these experiments. Well he would, wouldn't he ;-) Sure. I would have too. It's just that he was operating under the umbrella of classical rationalism. His experiment ought to work; it was just too simple not to work. And yet it didn't. And he could conceive of no reasonable explanation. And it's taken more than a full century now to explain why it didn't work and how it can work. You remember the "less than 10% of anticipated experimental results" Michelson did manage to obtain? I think they came from the part of light polarized normal to the axis of rotation not preferentially excluded by the splitting mirror. Fine by me except I don't really know what you mean by "galilean" except I assume from what you say you mean an inert aether. The term is used quite often to indicate an aether in which Galilean relativity applies: http://en.wikipedia.org/wiki/Princip...ean_relativity I'm sure you know of the principle so perhaps you haven't come across the term being applied to distinguish between aether theories. True. I've heard of Lorentzian aether and Lorentzian aether drift. Interesting, I haven't heard of the latter since the Lorentz transforms mean any drift speed becomes undetectable. Well "Lorentzian aether" is really only my term. Since I don't really care about the aether I haven't bothered to classify these kinds of things rigorously. The aether is there and presumably is has some kind of properties in what terms I really couldn't say. The fact that light travels through it as a medium is all that's really necessary to conduct relative motion experiments of the Michelson-Morley type. Apart from that I've only heard of the aether in purely inert terms. "Inert"? That may be "Galilean" by another name. Probably. By "inert" I just mean the aether doesn't participate in and isn't an experimental variable in relative motion studies of the Michelson-Morley variety. If you want to pick up the other conversation, by all means do so. There shouldn't be a problem discussing the table and confirming Kepler's Law since we can check all my figures with a calculator if you like and your welcome to trim the rest if you feel it would become argumentative. You know, George, I really don't doubt your numbers or Kepler's Law. What puzzles me though are that we have the inverse square law of gravitational attraction where f~1/rr and I'm just trying to reconcile that in my own mind as producing some kind of specific different orbital velocities at different r's for circular orbits.The web source I went to confirmed Kepler's Third Law but used it to justify inverse square gravitational force instead of vice versa. I don't mind revisiting the issue but it's difficult to sit down and put all the conceptual blocks in order to do the calculations to get tt~rrr. Same reason I haven't revisited my explanation for the Pioneer anomaly yet. I just don't want to crunch the numbers. In fact I never wanted to and if I hadn't run into that serendipitous coincidence I would never have raised the issue at all except in purely speculative terms. You don't need to do the numbers, try working through the equations in small steps. Start with the gravitational force as inverse square. Turn the equation for centrifugal force in terms of speed and radius around and find the speed to balance the gravitational force. Find the circumference from the radius and divide the circumference by the speed to get the period. (E&OE) Yeah, George, I know. Fact is everything you see me talking about here and in previous posts is all the product of twenty years ago. Then I knew I'd have to calculate the compound effect of relative path length and conjugate frequency dilation to prove it actually consistently worked in mechanical terms in three dimensional trigonometric terms. So I got some trig books out of the library and started crunching numbers. Eventually the numbers ran to several typed pages and the last equation was at least a couple of pages in length. And I knew I'd have to make an effort to calculate the anomalous perihelion advance of Mercury to have any kind of credibility whatsoever. So I went to the library and researched some numbers on the distribution of mass and velocities of rotation within the sun to calculate the effect of what I call "gravitational doppler". (Fortunately the library lay at the foot of my street.) But that was twenty years ago and now I'm really not so sure I care all that much anymore. Now I'm really more just talking concepts and willing to leave the calculations to others. ~v~~) [. . .] With the type of constraints proposed by you for conducting a physical measurement, I also feel that the verification of the notion of 'length contraction' through physical measurements may not really be possible. Under the circumstances, I agree that we should explore the possibility of using some indirect methods like improved MMX. By improved MMX, I mean a MMX type experiment where instead of comparing the phase difference in two beams of light on perpendicular arms, we could compare the actual pulse propagation times over the perpendicular arms. If you agree, I may propose a more detailed feasibility for physically conducting such an improved MMX type experiment. I disagree here, Gurcharn, with the particulars you suggest. I consider phase comparison perfectly adequate for an improved Michelson-Morley experiment. Sorry Lester, here I too cannot agree with you. Phase comparison in MMX leads to misleading interpretation of the result precisely due to the assumption of invariant nature of frequency f with the motion of emitters and reflectors. Well I can agree with your observation, Gurcharn, in general terms. But the difficulty can be resolved as outlined above in my message to George. Nor do I understand exactly how you would go about comparing actual pulse propagation times if not by means of phase comparisons. Kindly refer to my previous discussions with George in this thread at Sl. No. 13 onwards. http://groups.google.com/groups?as_u...oglegroups.com GSS In any event the only requirement for a successful version of MM would be to conduct the experiment using only light with its E vector polarized normal to the plane of platform rotation. As I remember I mentioned this to George early on before we began quibbling over various unrelated issues. I've done the 3D trig analysis for what I call frequency conjugation together with Lorentz transforms for the anisotropic dilation in the relative speed of light and it shows the anticipated results for MM should be realizeable. ~v~~ |
#3
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
Lester Zick wrote: Jeff Root: I get what you are arguing: The amount of contraction seen in an object at a given point in space is different for observers moving at different speeds relative to the thing being observed. And that seems self-contradictory. Not quite, Jeff. Let me show you an example: We have two interstitial bodies traveling at different velocities with overlapping geometric SR frames of reference, AF and CD which align in the following way: A--------------(C---v2------D)------v1-----------F In the above diagram: 1) which parts represent the "two interstitial bodies"? 2) "interstitial" means in the gap between something, what are the bodies between and what represents those items in the diagram? 3) What are the "different velocities" of the two bodies? 4) You say "AF" and "CD" are names of your frames but have shown the letters "A", "F", "C" and "D" as separated. What does that signify? 5) You show lines of "-" with "" and "" which seem to imply vectors with associated values "v1" and "v2". Are the start points "A" and "D" then to be taken as the origins of the frames "AF" and "CD" respectively? 6) Are the vectors from A to F and from D to C: a) displacement vectors of two objects moving from location A to F and from D to C in the respective frames? b) velocity vectors of the frames themselves and if so i) are "v1" and "v2" the velocities of the frames ii) in what third frame do AF and CD have those velocities? c) indications of the sense of one of the axes of the frames since you say they "align in the following way" (e.g. do you mean the X axis coordinates in frame AF increase to the right while those in CD increase to the left)? If so, shouldn't the second frame be named "DC" for consistency? And different MM type experiments are conducted across CD and across AF by observers in each frame of reference at the same time. These do not appear to be shown in the diagram. Please add them and label the arms so we can discuss them more easily, or at least add the arms that lie in the direction shown in the diagram (I hope we can assume there is no need to represent the transverse arms for this discussion). But since the velocity of AF is different from the velocity of CD different contraction factors would have to apply to each. However because AF and CD overlap one another in space this cannot be. Untrue, the factor depends on the speed of the object relative to the observer so there is no problem. However, this will be easier to explore when you clarify the ambiguities in your diagram. George |
#4
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
On Fri, 22 Dec 2006 10:23:17 -0000, "George Dishman"
wrote: "Lester Zick" wrote in message .. . On Thu, 21 Dec 2006 10:02:52 -0000, "George Dishman" wrote: "Lester Zick" wrote in message ... On Mon, 18 Dec 2006 23:38:36 -0000, "George Dishman" wrote: snip pointless 'who wrote what' argument The we need to clear something up. A frame is a coordinate system like a transparent sheet with a grid scribed on it. Which is velocity dependent and contracts and expands to explain the null results of MM class experiments at different velocities No, the overlapping grids have spacings that are dependent on the velocity of one grid with respect to the other Which is just another way of saying the same thing. The next word after where you snipped was "but". I almost agree with the first half of your sentence though there is a subtle differenc in the way I would word it, but I disagree with the part that says coordinate effects alone are taken to explain the MMX. I don't know what you mean by "snipped". I rarely "snip" material. I intersplice my comments to show exactly what I'm referring to. When material is snipped I almost invariably insert "[. . .]" to indicate where material has been deleted. You claim spatial coordinate geometry is a dependent variable of velocity through space but don't show the mechanics of that dependency and how it changes in accordance with velocity. You say it does but don't show how it can. Well I have shown it but you said you didn't see how rotation of the axes could be connected. I can illustrate that graphically but from past experince you won't look at that. Because illustrations are not explanations. There are two problems here, showing how changes in the coordinate geometry of space can vary with respect to velocity through space .. Not "with respect to velocity through space", it varies with the velocity of the frame with respect to the other frame. And that relative velocity is through space. .. when velocity through one and the same space is itself a dependent variable of that same space and its coordinate geometry and second showing what mechanics are involved in changes to the dependent coordinate geometry of space as a function of velocity. In other words if you claim as you appear to that spatial coordinate geometry is a function of velocity through space you're making spatial coordinate geometry a function of itself. but that is not the explanation of the MMX. The MMX is explained by the fact that the speed of light is isotropic in the rest frame of the equipment or, from the point of view of another frame, that there is a change of measured length of the arms of the equipment due to the velocity of the arm in that frame. Well sure except that's the same as saying there is contraction of some kind whether material or geometric and that that's the explanation for the null results of MM. Yes, there is a contraction but the key is what you are ignoring, the difference between the geometric and a 'material' or 'physical' contracton. Only because I don't understand what you mean by a difference between the two. Material geometry is part of geometry. If you have geometric contraction you have material contraction. And if you don't have material contraction you don't have geometric contraction. And if you don't have either you don't have an explanation for the results of MM. The isotropy of a constant speed of light was just Einstein's postulate which he extrapolated and applied through hypothetical contraction to explain the impossibility of positive results for relative motion studies such as MM. The contraction is a consequence of the postulates, not a separate effect as your words seem to imply. I'm not sure if you meant it that way. The mechanics of contraction is what I'm after and not the mechanics of postulates. The Lorentz transformations are anisotropic. Einstein's postulates are isotropic. It's the mechanics of one in relation to the other that I'm talking about. It's the mechanism which renders anisotropic characteristics isotropic that contraction is supposed to explain whether the mechanism is material or geometric. SR explains that change of length not as a physical contraction (like thermal changes) but as a rotation in the x-t plane due to the relative motion. I don't know what the latter means .. That is the one area that is at the root of all our disagreements. Okay but it's your claim not mine. If you want to use it to justfiy the conversion of Lorentzian anisotropy in the context of MM to Einstein's isotropy it's your responsibility to explain how the transformation occurs and not mine. .. but if it doesn't explain length changes as an actual effect .. It does. the Lorentz transformations would still apply nonetheless and should still produce positive experimental results in MM. Other way round, if it didn't produce an actual effect then the Lorentz transformations would *not* apply and there should still positive experimental results in MM. The problem here is that we have the null results of MM and we have the Lorentz transformations which are anisotropic and describe the mechanics involved in MM accurately to the best of our understanding. So if there is no material contraction those transformations should still apply and produce positive results. But either way the Lorentz transformations still apply and Einstein's isotropy would still have to explain why and how they're vitiated to produce the null results. The Lorentz transformations are only concerned with the relative longitudinal and transverse speed of light with respect to an experimental platform and not with any rotations in space. Not rotation in space, rotation in spacetime. Then I still don't have any idea what that means. The Lorentz transformations are what they are in space and the relative longitudinal and transverse speeds of light with respect to an experimental plaform don't change in space just because you or anyone else claims some rotation doesn't occur in space unless you can explain how some rotation in non space is supposed to affect their velocity in space. We're talking about actual relative velocities through space here and not just how they're measured. and has trouble explaining those results when overlapping grids are supposed to apply to the same area of space together. It has no problem at all, you can overlay as many mathematical grids on the universe as you like, as I have said many times before. The arm of an MMX can have as many lengths as there as frames in which it is measured. Not if the arms overlap each other in different frames of reference. I was talking of a single arm. A single arm can have as many lengths as there as frames in which it is measured. And a single experimental arm can have as many interstitial arms within it as there are frames of reference among which the experiments are conducted. That's what I was talking about. And different contraction factors would apply to each such that no uniform contraction factor can apply to all regardless of how any are measured to produce the null results of MM. What cannot happen of course is to have two different lengths for the same body measured in the same frame, but that never arises so there is no contradiction, you have yet to identify any problem. There is a problem if two different arms are supposed to have two different lengths in two different frames of reference together. Two arms, A and B measured in two frames K0 and K1 can give four different lengths: A in K0, A in K1, B in K0 and B in K1. I don't see any contradiction in that. If arms overlap one another it doesn't matter how they're measured. They can't uniformly contract in such a way as to produce the null results of MM conducted along both arms in different reference frames together. Your reference "for the same body measured in the same frame" is possible as well but not definitive because the same contraction factor would apply to both. Yes, that's the trivial case. However when the same bodies are interstitial and overlap one another in different frames of reference different contraction factors apply to each and that's where the contradiction occurs. Why, they have different values because they are measured in different frames so there is no contradiction. If they were supposed to have different values _without_ some other change then I could see your point but not when there is an obvious cause for the difference. It really doesn't matter how they're measured. It can't happen. Let's supposed for the sake of argument there is some other operative factor we'll call X whether it's your rotation in spacetime or anything else. The problem is that X has to transform Lorentz's transformations which are anisotropic into Einstein's or anyone elses isotropic results. You have at least two different contraction factors M and N which are applicable to a common overlapping area of space occupied by the overlapping interstitial experimental arms. So application of any one contraction factor to that common space either averages out with the other contraction factor or can't apply uniformly. So a uniformly null result is not possible for both experiments.Even if X is your rotation in spacetime two different rotations for one area of space cannot occur to make Lorentz's transformations uniformly isotropic in both. ~v~~ |
#5
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
Repeating my previous reply of the 24th in reply to your
copy in the original thread: "George Dishman" wrote in message ... "Lester Zick" wrote in message ... On Fri, 22 Dec 2006 10:23:17 -0000, "George Dishman" wrote: "Lester Zick" wrote in message ... On Thu, 21 Dec 2006 10:02:52 -0000, "George Dishman" wrote: "Lester Zick" wrote in message om... On Mon, 18 Dec 2006 23:38:36 -0000, "George Dishman" wrote: snip pointless 'who wrote what' argument The we need to clear something up. A frame is a coordinate system like a transparent sheet with a grid scribed on it. Which is velocity dependent and contracts and expands to explain the null results of MM class experiments at different velocities No, the overlapping grids have spacings that are dependent on the velocity of one grid with respect to the other Which is just another way of saying the same thing. The next word after where you snipped was "but". I almost agree with the first half of your sentence though there is a subtle differenc in the way I would word it, but I disagree with the part that says coordinate effects alone are taken to explain the MMX. I don't know what you mean by "snipped". A better word would have been "broke", I meant the point at which you interposed your comment, not that you had removed anything. I have no objection to what you did at all, I was merely clarifying that I had been mostly agreeing up to there as your reply seemed to treat it as a disagreement. I rarely "snip" material. I intersplice my comments to show exactly what I'm referring to. When material is snipped I almost invariably insert "[. . .]" to indicate where material has been deleted. You claim spatial coordinate geometry is a dependent variable of velocity through space but don't show the mechanics of that dependency and how it changes in accordance with velocity. You say it does but don't show how it can. Well I have shown it but you said you didn't see how rotation of the axes could be connected. I can illustrate that graphically but from past experince you won't look at that. Because illustrations are not explanations. Explanations are tansfers of understanding and the method by which that is communicated makes no difference. Whether I explain in maths or words or as a diagram or even if I present it as a Broadway musical, as long as you grasp my meaning the medium is irrelevant. There are two problems here, showing how changes in the coordinate geometry of space can vary with respect to velocity through space .. Not "with respect to velocity through space", it varies with the velocity of the frame with respect to the other frame. And that relative velocity is through space. You cannot measure or define speed relative to the vacuum, what I said is correct, the velocity used in the Lorentz transforms and derived length contraction formula relate to frames and objects, not space itself. Well sure except that's the same as saying there is contraction of some kind whether material or geometric and that that's the explanation for the null results of MM. Yes, there is a contraction but the key is what you are ignoring, the difference between the geometric and a 'material' or 'physical' contracton. Only because I don't understand what you mean by a difference between the two. I can see that so I have to find a better way to communicate what I mean. Once you grasp that, then you can argue about it if you want to. I'll try to do something after Christmas. ... The mechanics of contraction is what I'm after and not the mechanics of postulates. The Lorentz transformations are anisotropic. Einstein's postulates are isotropic. It's the mechanics of one in relation to the other that I'm talking about. It's the mechanism which renders anisotropic characteristics isotropic that contraction is supposed to explain whether the mechanism is material or geometric. Fine but so far when I have explained in words, you haven't followed and said you saw "no connection". I need to find a better way to communicate. SR explains that change of length not as a physical contraction (like thermal changes) but as a rotation in the x-t plane due to the relative motion. I don't know what the latter means .. That is the one area that is at the root of all our disagreements. Okay but it's your claim not mine. If you want to use it to justfiy the conversion of Lorentzian anisotropy in the context of MM to Einstein's isotropy it's your responsibility to explain how the transformation occurs and not mine. It's not my responsibility to teach anything, if you want to learn SR it is your responsibility to study it. Taylor and Wheeler would probably be the best book to use. However, I will try to explain sometime in the holidays. Words don't work for you so I'll have to try something else. .. but if it doesn't explain length changes as an actual effect .. It does. the Lorentz transformations would still apply nonetheless and should still produce positive experimental results in MM. Other way round, if it didn't produce an actual effect then the Lorentz transformations would *not* apply and there should still positive experimental results in MM. The problem here is that we have the null results of MM and we have the Lorentz transformations which are anisotropic and describe the mechanics involved in MM accurately to the best of our understanding. So if there is no material contraction those transformations should still apply and produce positive results. But either way the Lorentz transformations still apply and Einstein's isotropy would still have to explain why and how they're vitiated to produce the null results. That's something you can do for yourself. Consider a flash of light being split and travelling down the two arms, being reflected and returning to the splitter. Define events for each of those interactions and find their coordinates in the rest frame of the arms. Then apply the Lorentz transforms to the events to get them in some other frame. Then calculate the time difference for the events relating to the light returning to the splitter. You will see how it all works out. The Lorentz transformations are only concerned with the relative longitudinal and transverse speed of light with respect to an experimental platform and not with any rotations in space. Not rotation in space, rotation in spacetime. Then I still don't have any idea what that means. The Lorentz transformations are what they are in space ... No, remember the transforms work on all four coordinates. ... and the relative longitudinal and transverse speeds of light with respect to an experimental plaform don't change in space just because you or anyone else claims some rotation doesn't occur in space unless you can explain how some rotation in non space is supposed to affect their velocity in space. We're talking about actual relative velocities through space here and not just how they're measured. and has trouble explaining those results when overlapping grids are supposed to apply to the same area of space together. It has no problem at all, you can overlay as many mathematical grids on the universe as you like, as I have said many times before. The arm of an MMX can have as many lengths as there as frames in which it is measured. Not if the arms overlap each other in different frames of reference. I was talking of a single arm. A single arm can have as many lengths as there as frames in which it is measured. And a single experimental arm can have as many interstitial arms within it .. "between it", interstitial means between. .. as there are frames of reference among which the experiments are conducted. That's what I was talking about. And different contraction factors would apply to each such that no uniform contraction factor can apply to all regardless of how any are measured to produce the null results of MM. Each speed gives uniform contraction to object moving with uniform (meaning the same) speed. All the parts of any one MMX are moving with uniform speed so it works. Any other MMX moving at a different speed still has all its parts moving that the same "uniform" speed so you get "uniform contraction". Still no problem What cannot happen of course is to have two different lengths for the same body measured in the same frame, but that never arises so there is no contradiction, you have yet to identify any problem. There is a problem if two different arms are supposed to have two different lengths in two different frames of reference together. Two arms, A and B measured in two frames K0 and K1 can give four different lengths: A in K0, A in K1, B in K0 and B in K1. I don't see any contradiction in that. If arms overlap one another it doesn't matter how they're measured. They can't uniformly contract in such a way as to produce the null results of MM conducted along both arms in different reference frames together. Since each is moving at uniform speed, there isn't a problem. If they aren't separated in the direction perpendicular to the motion of course the bodies will impact, but that's hardly a concern for the Lorentz Transforms, only those standing nearby :-) Your reference "for the same body measured in the same frame" is possible as well but not definitive because the same contraction factor would apply to both. Yes, that's the trivial case. However when the same bodies are interstitial and overlap one another in different frames of reference different contraction factors apply to each and that's where the contradiction occurs. Why, they have different values because they are measured in different frames so there is no contradiction. If they were supposed to have different values _without_ some other change then I could see your point but not when there is an obvious cause for the difference. It really doesn't matter how they're measured. It can't happen. Let's supposed for the sake of argument there is some other operative factor we'll call X whether it's your rotation in spacetime or anything else. The problem is that X has to transform Lorentz's transformations which are anisotropic into Einstein's or anyone elses isotropic results. Try working the example I suggested above and you will see that works OK. You have at least two different contraction factors M and N which are applicable to a common overlapping area of space occupied by the overlapping interstitial experimental arms. No, M is uniformly applicable to all of one MMX while N is uniformly applicable to all of the other. Each applies to bodies moving at a one particular speed. So application of any one contraction factor to that common space either averages out with the other contraction factor or can't apply uniformly. That makes no sense at all. One and only one factor applies to each observer since the factor is dependent on the speed of the observer relative to the body. So a uniformly null result is not possible for both experiments.Even if X is your rotation in spacetime two different rotations for one area of space cannot occur to make Lorentz's transformations uniformly isotropic in both. Put two stakes in the ground a metre apart. Stand 10m from the midpoint where your line of sight to the midpoint makes an angle of 30 degrees to the line between the stakes. Have a friend stand 10m from the midpoint but at 45 degrees. The angle subtended for each of you is 'contracted' compared to what you would see if your line of sight was perpendicular to the line between the stakes. You see different 'contraction factors' because you are standing in different places. Now add two more stakes but set the line between them at 10 degrees to that between the original pair. To ensure they "overlap in space", make sure the midpoints coincide. Again you and your friend see different factors but they are not the same as the first pair. For the Lorentz Transforms, the values depend on speed instead of location but other than that there is no difference in the _logic_. Your argument doesn't show any contradiction. George |
#6
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
Lester, this is a copy of another of my replies posted in
the original thread since you are moving everything here. "George Dishman" wrote in message ... "Lester Zick" wrote in message ... On 20 Dec 2006 05:37:23 -0800, "George Dishman" wrote: Lester Zick wrote: On 19 Dec 2006 00:41:10 -0800, "George Dishman" wrote: Lester Zick wrote: On 18 Dec 2006 00:40:59 -0800, "George Dishman" wrote: Lester Zick wrote: ... you seem to be making a consistent error of assuming SR frames of reference are not velocity dependent and are somehow static. George, this is incorrect. The fourth dimension in SR is time whatever that means. The first three spatial dimensions don't have any velocity and don't move through space as a function of time or anything else. They're simply static ... ... You're confusing frames of reference with objects in them, George. Both your comments were regarding frames, not objects. First you say I'm making an error in thinking they are "somehow static", then you say "They're simply static". Objects have velocity and move through space. Frames of reference are determined in accordance with the common velocity of objects in them. So if the objects are in relative motion, so are the spatial coordinate systems defined by them. Sorry Lester, SR explains velocity as a rotation. It also deals perfectly well with both accelerated objects in inertial frames and even accelerated frames but that is a different topic. Perfectly fascinating, George. Next you'll be claiming SR explains the grinch who stole Christmas too. Just filling you in on some basic facts. Thinking that SR only applies to inertial frames is a common misconception. No Lester, the difference between on frame and another is that the origin of one is in motion in the other. That speed is what goes into the Lorentz Transforms to convert coordinates in one into equivalent coordinates in the other. The velocity associated with a frame of reference goes into the Lorentz transforms, George. Yes Lester, that's what I just said. That doesn't mean a frame of reference moves with respect to others. Yes it does. The velocity that goes into the transforms to convert coordinates in one system into coordinates in the other is that of the origin of the second system in the first. You've obviously never tried to use the theory in practice. Whatever, George. Maybe Gurcharn has the patience to deal with all your various and sundry misconceptions regarding SR but I don't. No misconceptions Lester, just the basic introductory groundwork for SR that it seems you have never before encountered. Well, George, SR has nothing to do with rotation for the reason noted above. Sorry Lester, that is wrong. You really need to read some textbooks. And you really need some accurate information, George, .. It is accurate, and it is just the basics of the theory. Most modern textbooks explain it that way as it is an essential precursor to GR, though some older texts tried to use the old 'relativistic mass' style of approach. Noting that a change of velocity of an object is a rotation of its worldline is the basis of SR. Yadayada whatever. More buzzwords. Velocity? Rotation? Maybe you are puzzled by "worldline". It is the standard jargon of the subject Lester, everyone who studies the subject it at any level knows what a worldline is. I'm not interested in a song and dance where you can't even explain what you're talking about in so many words that are supposed to connect up with one another. So open a book on the subject and find out what they mean. So far it looks as though you've tried to figure it out for yourself and all you've done is re-invent Lorentz's aether. George |
#7
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
On 29 Dec 2006 03:54:29 -0800, "George Dishman"
wrote: Repeating my previous reply of the 24th in reply to your copy in the original thread: Once more unto the google breach I fear, George. No idea why your previous reply never showed up on the original thread. Didn't press because of the holidays. Just out of curiosity is this post showing up on the new thread or am I still stuck on the old? "George Dishman" wrote in message ... "Lester Zick" wrote in message ... ~v~~ |
#8
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
"Lester Zick" wrote in message ... On 29 Dec 2006 03:54:29 -0800, "George Dishman" wrote: Repeating my previous reply of the 24th in reply to your copy in the original thread: Once more unto the google breach I fear, George. No idea why your previous reply never showed up on the original thread. What a pain. I'm going to have to raise a ticket with them, this is getting beyond a joke. Didn't press because of the holidays. Just out of curiosity is this post showing up on the new thread or am I still stuck on the old? This is in the new thread, only the content was copied from the old. You should be able to use this link to see your message to which I replied: "Lester Zick" wrote in message ... George |
#9
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
On 29 Dec 2006 03:54:29 -0800, "George Dishman"
wrote: Repeating my previous reply of the 24th in reply to your copy in the original thread: George, since your post is a reply to your original reply to me I may miss certain of your comments which appear as previously posted material. If I overlook something of importance please let me know. But I think this post-reply sequence has gotten long enough and I would like to trim it down to some kind of basics if you don't mind. "George Dishman" wrote in message ... "Lester Zick" wrote in message ... On Fri, 22 Dec 2006 10:23:17 -0000, "George Dishman" wrote: "Lester Zick" wrote in message m... On Thu, 21 Dec 2006 10:02:52 -0000, "George Dishman" wrote: "Lester Zick" wrote in message news:crfjo25d95k8gm2ie0cfitg51mtebvn0c6@4ax. com... On Mon, 18 Dec 2006 23:38:36 -0000, "George Dishman" wrote: *********************************** snip pointless 'who wrote what' argument The we need to clear something up. A frame is a coordinate system like a transparent sheet with a grid scribed on it. Which is velocity dependent and contracts and expands to explain the null results of MM class experiments at different velocities No, the overlapping grids have spacings that are dependent on the velocity of one grid with respect to the other Which is just another way of saying the same thing. The next word after where you snipped was "but". I almost agree with the first half of your sentence though there is a subtle differenc in the way I would word it, but I disagree with the part that says coordinate effects alone are taken to explain the MMX. I don't know what you mean by "snipped". A better word would have been "broke", I meant the point at which you interposed your comment, not that you had removed anything. I have no objection to what you did at all, I was merely clarifying that I had been mostly agreeing up to there as your reply seemed to treat it as a disagreement. Got it. When two or more thoughts are contained in a single paragraph I occasionally interpolate replies to show exactly what I'm commenting on. In any event if there is no serious disagreement then I'd like to omit this whole section. I'll post rows of asterisks to delimit what I think we might omit. I rarely "snip" material. I intersplice my comments to show exactly what I'm referring to. When material is snipped I almost invariably insert "[. . .]" to indicate where material has been deleted. ******************************* You claim spatial coordinate geometry is a dependent variable of velocity through space but don't show the mechanics of that dependency and how it changes in accordance with velocity. You say it does but don't show how it can. Well I have shown it but you said you didn't see how rotation of the axes could be connected. I can illustrate that graphically but from past experince you won't look at that. Because illustrations are not explanations. Explanations are tansfers of understanding and the method by which that is communicated makes no difference. Whether I explain in maths or words or as a diagram or even if I present it as a Broadway musical, as long as you grasp my meaning the medium is irrelevant. Well the problem is whether I grasp your meaning in the same way you do.It's the same problem I've always had with analogical and exemplary arguments. It's the socratic dialectical method cast in the form of pictures or anything else such as a stage play or whatever. Socrates used to reason expositionally by dialectical example and analogy instead of analytically. The problem is that there is no guarantee what his examples may actually have meant in universal terms. All we have is his word or claim that this or that analogy or example really conveyed this or that meaning and not some other meaning entirely. This is exactly where modern mathematikers go wrong with their models. By and large they're just not exhaustive. It isn't that their models aren't accurate models; it's what exactly their accurate models are models of. And until we understand that in exact mechanical and universal terms there is no point to asserting that this or that model is a correct model for the point we're trying to establish. If you reflect on the rather disputatious discussions we had regarding globular clusters I seem to recollect that you or Jeff or perhaps both of you thought some pictures were worth a thousand words whereas I was of the opinion that conservation of angular momentum is dependent on and a product of radius and kinetic energy is not. So a depiction of any pictorial or other model which does not model that fundamental circumstance cannot be an accurate depiction. There are two problems here, showing how changes in the coordinate geometry of space can vary with respect to velocity through space .. Not "with respect to velocity through space", it varies with the velocity of the frame with respect to the other frame. And that relative velocity is through space. You cannot measure or define speed relative to the vacuum, what I said is correct, the velocity used in the Lorentz transforms and derived length contraction formula relate to frames and objects, not space itself. Yes but what we're, or at least I, am trying to establish is whether space is a void or vacuum and whether light travels through space at some constant velocity independent of objects in space and whether that velocity through space can be measured by means of MM or kindred experiments. That's the whole point to SR and my analysis of it and interstitial bodies and frames of reference. So there's no point to simply saying it ain't so since that's what we're trying to determine. Well sure except that's the same as saying there is contraction of some kind whether material or geometric and that that's the explanation for the null results of MM. Yes, there is a contraction but the key is what you are ignoring, the difference between the geometric and a 'material' or 'physical' contracton. Only because I don't understand what you mean by a difference between the two. I can see that so I have to find a better way to communicate what I mean. Once you grasp that, then you can argue about it if you want to. I'll try to do something after Christmas. Okay. I don't see that there can be a geometric contraction which doesn't affect objects measured according to the geometric metric but I'm certainly willing to listen. George, let me break this off here and respond to the balance of your post in another reply. ~v~~ |
#10
|
|||
|
|||
Interstitial Bodies & Reference Frames in SR
On 29 Dec 2006 03:54:29 -0800, "George Dishman"
wrote: Repeating my previous reply of the 24th in reply to your copy in the original thread: "George Dishman" wrote in message ... "Lester Zick" wrote in message ... [. . .] The mechanics of contraction is what I'm after and not the mechanics of postulates. The Lorentz transformations are anisotropic. Einstein's postulates are isotropic. It's the mechanics of one in relation to the other that I'm talking about. It's the mechanism which renders anisotropic characteristics isotropic that contraction is supposed to explain whether the mechanism is material or geometric. Fine but so far when I have explained in words, you haven't followed and said you saw "no connection". I need to find a better way to communicate. SR explains that change of length not as a physical contraction (like thermal changes) but as a rotation in the x-t plane due to the relative motion. I don't know what the latter means .. That is the one area that is at the root of all our disagreements. Okay but it's your claim not mine. If you want to use it to justfiy the conversion of Lorentzian anisotropy in the context of MM to Einstein's isotropy it's your responsibility to explain how the transformation occurs and not mine. It's not my responsibility to teach anything, if you want to learn SR it is your responsibility to study it. Taylor and Wheeler would probably be the best book to use. However, I will try to explain sometime in the holidays. Words don't work for you so I'll have to try something else. Okay. But I'm not interested in SR. I'm interested in geometric contraction as an explanation for the transition between Lorentz anisotropic transforms and Einsteins's isotropic results. If you maintain SR explains the transition in the context of interstitial bodies it is certainly your responsibility to explain how that is possible. .. but if it doesn't explain length changes as an actual effect .. It does. the Lorentz transformations would still apply nonetheless and should still produce positive experimental results in MM. Other way round, if it didn't produce an actual effect then the Lorentz transformations would *not* apply and there should still positive experimental results in MM. The problem here is that we have the null results of MM and we have the Lorentz transformations which are anisotropic and describe the mechanics involved in MM accurately to the best of our understanding. So if there is no material contraction those transformations should still apply and produce positive results. But either way the Lorentz transformations still apply and Einstein's isotropy would still have to explain why and how they're vitiated to produce the null results. That's something you can do for yourself. Consider a flash of light being split and travelling down the two arms, being reflected and returning to the splitter. Define events for each of those interactions and find their coordinates in the rest frame of the arms. Then apply the Lorentz transforms to the events to get them in some other frame. Then calculate the time difference for the events relating to the light returning to the splitter. You will see how it all works out. The Lorentz transformations are only concerned with the relative longitudinal and transverse speed of light with respect to an experimental platform and not with any rotations in space. Not rotation in space, rotation in spacetime. Then I still don't have any idea what that means. The Lorentz transformations are what they are in space ... No, remember the transforms work on all four coordinates. Which means what exactly with respect to interstitial bodies and coincident frames of reference? ... and the relative longitudinal and transverse speeds of light with respect to an experimental plaform don't change in space just because you or anyone else claims some rotation doesn't occur in space unless you can explain how some rotation in non space is supposed to affect their velocity in space. We're talking about actual relative velocities through space here and not just how they're measured. and has trouble explaining those results when overlapping grids are supposed to apply to the same area of space together. It has no problem at all, you can overlay as many mathematical grids on the universe as you like, as I have said many times before. The arm of an MMX can have as many lengths as there as frames in which it is measured. Not if the arms overlap each other in different frames of reference. I was talking of a single arm. A single arm can have as many lengths as there as frames in which it is measured. And a single experimental arm can have as many interstitial arms within it .. "between it", interstitial means between. So what? "Interstitial" meaning "between" can have as many frame of reference definitions as there are particles within arms moving at different velocities. .. as there are frames of reference among which the experiments are conducted. That's what I was talking about. And different contraction factors would apply to each such that no uniform contraction factor can apply to all regardless of how any are measured to produce the null results of MM. Each speed gives uniform contraction to object moving with uniform (meaning the same) speed. All the parts of any one MMX are moving with uniform speed so it works. Any other MMX moving at a different speed still has all its parts moving that the same "uniform" speed so you get "uniform contraction". Still no problem Uniform contraction is a speed dependent variable. The problem is that you can have different speeds within any MM experiment and different uniform contraction factors. What cannot happen of course is to have two different lengths for the same body measured in the same frame, but that never arises so there is no contradiction, you have yet to identify any problem. There is a problem if two different arms are supposed to have two different lengths in two different frames of reference together. Two arms, A and B measured in two frames K0 and K1 can give four different lengths: A in K0, A in K1, B in K0 and B in K1. I don't see any contradiction in that. If arms overlap one another it doesn't matter how they're measured. They can't uniformly contract in such a way as to produce the null results of MM conducted along both arms in different reference frames together. Since each is moving at uniform speed, there isn't a problem. If they aren't separated in the direction perpendicular to the motion of course the bodies will impact, but that's hardly a concern for the Lorentz Transforms, only those standing nearby :-) I don't understand what this means. Your reference "for the same body measured in the same frame" is possible as well but not definitive because the same contraction factor would apply to both. Yes, that's the trivial case. However when the same bodies are interstitial and overlap one another in different frames of reference different contraction factors apply to each and that's where the contradiction occurs. Why, they have different values because they are measured in different frames so there is no contradiction. If they were supposed to have different values _without_ some other change then I could see your point but not when there is an obvious cause for the difference. It really doesn't matter how they're measured. It can't happen. Let's supposed for the sake of argument there is some other operative factor we'll call X whether it's your rotation in spacetime or anything else. The problem is that X has to transform Lorentz's transformations which are anisotropic into Einstein's or anyone elses isotropic results. Try working the example I suggested above and you will see that works OK. I don't see anything of the kind. You've got at least two different contraction factors supposedly applicable to the same interstitial bodies and regions of space. You have at least two different contraction factors M and N which are applicable to a common overlapping area of space occupied by the overlapping interstitial experimental arms. No, M is uniformly applicable to all of one MMX while N is uniformly applicable to all of the other. Each applies to bodies moving at a one particular speed. The problem is that M and N overlap one another and light for each experiment has to pass through both. So application of any one contraction factor to that common space either averages out with the other contraction factor or can't apply uniformly. That makes no sense at all. One and only one factor applies to each observer since the factor is dependent on the speed of the observer relative to the body. I'm not talking about observers. I'm talking about the relative speed of light. That's what has to transit space to produce Einstein's isotropic effects. Lorentz transforms show the relative speed of light to be anisotropic. So a uniformly null result is not possible for both experiments.Even if X is your rotation in spacetime two different rotations for one area of space cannot occur to make Lorentz's transformations uniformly isotropic in both. Put two stakes in the ground a metre apart. Stand 10m from the midpoint where your line of sight to the midpoint makes an angle of 30 degrees to the line between the stakes. Have a friend stand 10m from the midpoint but at 45 degrees. The angle subtended for each of you is 'contracted' compared to what you would see if your line of sight was perpendicular to the line between the stakes. You see different 'contraction factors' because you are standing in different places. Now add two more stakes but set the line between them at 10 degrees to that between the original pair. To ensure they "overlap in space", make sure the midpoints coincide. Again you and your friend see different factors but they are not the same as the first pair. For the Lorentz Transforms, the values depend on speed instead of location but other than that there is no difference in the _logic_. Your argument doesn't show any contradiction. I don't see different contraction factors. The math of SR and Lorentz transforms show different contraction factors. And when different contraction factors overlap there is a contradiction between speed of light transiting one frame of reference and the other through common regions of space. ~v~~ |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Lester's overlapping bodies and frames in SR | George Dishman | Astronomy Misc | 0 | December 26th 06 01:57 PM |
Interstitial Bodies and Reference Frames in SR | Lester Zick | Astronomy Misc | 2 | December 25th 06 05:50 PM |
Dark frames | Thomas Womack | Amateur Astronomy | 7 | September 24th 04 10:54 PM |
Dark Frames | Stuart M | UK Astronomy | 5 | March 16th 04 04:18 PM |
ISS caught in a few frames | Robin Leadbeater | UK Astronomy | 4 | October 4th 03 11:44 PM |