A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: PD on 22 Feb 2010 09:54 On Feb 21, 4:23 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 21 Feb, 21:40, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Feb 20, 9:36 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > On 20 Feb, 05:27, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> > > > wrote: > > > > > If you're suggesting that it's improbable that a theory could work not > > > > because its premises were correct, but because it simply promoted > > > > correct behaviours, then wonders why religion has fared so well. In > > > > any event, I'm willing to accept Feynman's argument, basically that QM > > > > amounts to a workable mathematical model, and makes no claim to any > > > > truth more fundamental than that. > > > > > ________________________________ > > > > The whole of physics is like that, not just QM. Physics just gives us the > > > > eqns by which the universe functions. It does not make claim to any more > > > > truths fundamental than the eqns; the rest is just philosophy. > > > > > Your problem of course is that you don't understand the eqns, so you don't > > > > understand physics. > > > > On the contrary, my problem is that physics seems to have dispensed > > > with the physical. Yet it is the physical, as opposed to the > > > mathematical, that I am interested in. That is, the qualitative > > > physical concepts - what I've referred to as an explanation at the > > > the "practical-mechanical" level - that would seem to me to > > > distinguish physics from maths are largely absent, and indeed seem to > > > be systematically deprecated and devalued. > > > > And on top of this, there is an ideological arrogance on the part of > > > many in physics that is distasteful in light of their claims to > > > "objectivity" and "adherence to scientific principles". > > > > Indeed, your argument that "physics does not make claim to any truths > > > more fundamental than the eqns" is, itself, a philosophical position > > > and a statement of ideology - even though you refer disparagingly to > > > "the rest" as "just philosophy". > > > > This ideological position becomes even more detectable in the context > > > of grandiose claims that "physics gives us the eqns by which the > > > universe functions". > > > > Not only is that a total falsehood when interpreted literally and in > > > the context of history, but moreover I know from the context that you > > > do not mean "regrettably, physics has only given us the eqns..." or > > > even "physics has given us the eqns, and I'm unable to say if there is > > > a more complete description", what you really mean is "these eqns > > > provide a complete and final description of the physical world, and I > > > hold that nothing else is relevant to physics and nor am I concerned > > > with it". > > > > And what I object to is not the content of these staments, but the > > > constant concealment of your ideological beliefs beneath allusions to > > > objectivity and ideological and philosophical independence. > > > I note with interest that you at one point appeared to be interested > > in engaging in learning how it is that the speed of light could be the > > same, regardless of the motion of the source, or how it is that > > simultaneity could be frame-dependent. But your interest in the > > physics here quickly waned and you fell back to fussing about the > > sociology of scientists. What accounts for your short attention span > > for the physics? Note that in the discussions I was giving you, there > > was practically no math in favor of presentation of basic physical > > principles and their conceptual implications. > > Actually I was still interested in discussing the invariance of 'c', > and I do still have questions. Unfortunately, both threads appear to > have been partly taken over by other posters arguing completely > different points, and much of my own time and attention has once again > returned to addressing the quips, implicit insults, and general > "sociological" points raised. So let's get back to the physics. You had an array of sources and detectors. I suggested that the sources can be something real, like a flashbulb or a firecracker, which emits a very brief pulse of light in all directions. The detectors will be something that triggers when a pulse of light arrives at the detector. We can use a photodiode or a photomultiplier tube with hemispherical photocathode if you like. With this kind of arrangement, it is certainly possible to ask which detectors will trigger before, at the same time as, or after other detectors, though that answer may vary from reference frame to reference frame. Do you want to ask that question regarding a particular set-up of detectors and sources?
From: mpc755 on 22 Feb 2010 11:18 On Feb 21, 8:15 pm, mpc755 <mpc...(a)gmail.com> wrote: > On Feb 21, 2:01 pm, JT <jonas.thornv...(a)hotmail.com> wrote: > > > > > On 21 Feb, 18:51, mpc755 <mpc...(a)gmail.com> wrote: > > > > On Feb 21, 12:43 pm, Bruce Richmond <bsr3...(a)my-deja.com> wrote: > > > > > On Feb 21, 11:44 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > On Feb 21, 11:28 am, Bruce Richmond <bsr3...(a)my-deja.com> wrote: > > > > > > > On Feb 20, 11:21 pm, "Peter Webb" > > > > > > > <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > > > > > > > And if conducted in a laboratory in low earth orbit, with a relative speed > > > > > > > > of 25,000 kph relative to the ether - what will be the measured speed of > > > > > > > > light then? > > > > > > > > The light will be 'measured' to be 'c'. If the Observers in the > > > > > > > laboratory in low Earth orbit know how they are moving with respect to > > > > > > > the aether they will be able to determine the speed of light to be 'c' > > > > > > > with respect to the aether. > > > > > > > > ______________________________________ > > > > > > > So, according to you, in every inertial reference frame, the measured speed > > > > > > > of light is "c", completely independent of how the observer is moving > > > > > > > relative to the ether? > > > > > > > He is with good company on this point. Read the 1904 paper by > > > > > > Lorentz. > > > > > > >http://en.wikisource.org/wiki/Electromagnetic_phenomena > > > > > > > "It is to be remarked that the formulae for a system without > > > > > > translation are implied in what precedes. For such a system the > > > > > > quantities with accents become identical to the corresponding ones > > > > > > without accents; also k=1 and l=1. The components of (27) are at the > > > > > > same time those of the electric force which is exerted by one > > > > > > polarized particle on another." > > > > > > > Lorentz showed that the moving observer would measure the speed of > > > > > > light to be c in his own frame. Because of this there is no way to > > > > > > tell if you are at rest WRT the ether. But that doesn't prevent you > > > > > > from translating to the coordinates of another frame. If you just > > > > > > consider yourself to be at rest WRT the ether and work it out you get > > > > > > the same answer as you get by doing a two step translation from your > > > > > > frame to the ether to the other frame. Assuming you are at rest WRT > > > > > > the ether gives the same math as SR. > > > > > > > Bruce > > > > > > I think where I differ from Lorentz is in the 'ticking' rate of atomic > > > > > clocks. Two frames are moving relative to one another. I think Lorentz > > > > > is saying each Observer in a reference frame 'sees' the other > > > > > Observer's clock as 'ticking' slower than their own. This I disagree > > > > > with. The more at rest with respect to the aether an atomic clock is > > > > > the faster it 'ticks'. If the embankment is at rest with respect to > > > > > the aether and the train is moving with respect to the aether then the > > > > > clock on the embankment 'ticks' faster than the clock on the train. > > > > > But you don't *know* that the embankment is at rest WRT the ether. > > > > All you really know is how their clock syncs relate to each other due > > > > to their relative motion. > > > > Correct. But what about length contraction at speeds near 'c'. Won't > > > the train moving near 'c' with its shorter measuring rod measure the > > > train at rest with respect to the embankment to be longer and vice > > > verse? Where the train at rest with respect to the embankment and its > > > longer measuring rod to measure the train moving near 'c' with respect > > > to the aether to be shorter? > > > Good point since they claim mutual time dilation and their is no > > prefered rest frame, how can they even claim that one object should be > > the contracted one.... > > > Well i asked them so many times, but their theory lack consistency > > most paradoxes and answers is just AdHoc speculation and lack total > > connection with reality. So i do not expect you to get an answer at > > that question. > > > JT > > That's where Aether Displacement is different. In Aether Displacement > everything is with respect to the aether. I discuss the frames of > reference as being more, or less, at rest with respect to the aether. > > I also like Einstein's description of the aether as, "the state of the > [ether] is at every place determined by its connections to the matter > and the state of the ether in neighboring places". > > Since the aether exists through out the Earth surrounding each nuclei > which is the matter which is the Earth, the aether at the surface of > the Earth is at rest, or almost at rest, with respect to the surface > of the Earth. > > If the embankment is at rest with respect to the surface of the Earth > and the train is moving with respect to the embankment, the embankment > is more at rest with respect to the aether than the train is. > > If the train is moving relative to the embankment then the frames of > reference are not equal because they both do not exist in the same > state with respect to the aether. > In the above, the train and the embankment both occupy the same three dimensional space. Think of the train as consisting of flat bed cars which ride under the light from the lightning strikes at A/A' and B/ B'. This qualification is important. At this time, I am not interested in applying the idea of motion to the aether in terms of the embankment having 'its own' aether and the train having 'its own' aether. If you look at the following animation and consider water to be at rest with respect to the embankment and water to be at rest with respect to the train you can see what I am trying to avoid (for now at least). Look at the light waves as the propagating through the water at rest with respect to the embankment from A and B towards M and the light waves propagating through the water at rest with respect to the train from A' and B' towards M'. Ignore the waves which move from the train to the embankment and vice verse, they are not accurate: http://www.youtube.com/watch?v=jyWTaXMElUk If the train was encased in lead and the embankment was encased in lead would the aether be 'at rest' inside the lead encasing? At this point, I don't know, but my guess is know. Constant momentum means constant momentum with respect to the aether for each and every nuclei which is the matter which is the train. What I have not yet been able to figure out in terms of the terminology is how to describe constant momentum and the increase in the aether pressure associated with increased momentum at the same time allowing for there to be momentum. In other words, the faster the lead train is moving with respect to the aether the more aether pressure there is exerted on each and every nuclei which is the matter which is the train. But the train still has momentum. The faster the momentum the more aether is displaced but the more aether there is 'displacing back'. Each and every nuclei in the lead train is not at rest with respect to the aether but the aether does not effect the nuclei, and the trains, momentum. The aether does not cause momentum to cease because whatever energy each and every nuclei requires to displace the aether the aether returns to the nuclei as it 'displaces back'. > > > I still prefer Einstein's concept of "the state of the [ether] is at > > > every place determined by its connections with the matter and the > > > state of the ether in neighboring places" versus an 'absolutely > > > stationary space'. > > > > The state of the aether's displacement is at every place determined by > > > its connections with the matter and the state of the aether in > > > neighboring places. > > > > Since matter and aether are different states of the same material, the > > > aether is displaced by the matter. A moving C-60 molecule has an > > > associated aether displacement wave. > > > > > > The Observer on the embankment and the Observer on the train will > > > > > arrive at the same conclusion which is the clock on the embankment > > > > > 'ticks' faster than the clock on the train.- Hide quoted text - > > > > > > - Show quoted text -- Dölj citerad text - > > > > - Visa citerad text -- Dölj citerad text - > > > > - Visa citerad text - > >
From: mpc755 on 22 Feb 2010 11:26 On Feb 22, 11:18 am, mpc755 <mpc...(a)gmail.com> wrote: > On Feb 21, 8:15 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > > On Feb 21, 2:01 pm, JT <jonas.thornv...(a)hotmail.com> wrote: > > > > On 21 Feb, 18:51, mpc755 <mpc...(a)gmail.com> wrote: > > > > > On Feb 21, 12:43 pm, Bruce Richmond <bsr3...(a)my-deja.com> wrote: > > > > > > On Feb 21, 11:44 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > > On Feb 21, 11:28 am, Bruce Richmond <bsr3...(a)my-deja.com> wrote: > > > > > > > > On Feb 20, 11:21 pm, "Peter Webb" > > > > > > > > <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > > > > > > > > And if conducted in a laboratory in low earth orbit, with a relative speed > > > > > > > > > of 25,000 kph relative to the ether - what will be the measured speed of > > > > > > > > > light then? > > > > > > > > > The light will be 'measured' to be 'c'. If the Observers in the > > > > > > > > laboratory in low Earth orbit know how they are moving with respect to > > > > > > > > the aether they will be able to determine the speed of light to be 'c' > > > > > > > > with respect to the aether. > > > > > > > > > ______________________________________ > > > > > > > > So, according to you, in every inertial reference frame, the measured speed > > > > > > > > of light is "c", completely independent of how the observer is moving > > > > > > > > relative to the ether? > > > > > > > > He is with good company on this point. Read the 1904 paper by > > > > > > > Lorentz. > > > > > > > >http://en.wikisource.org/wiki/Electromagnetic_phenomena > > > > > > > > "It is to be remarked that the formulae for a system without > > > > > > > translation are implied in what precedes. For such a system the > > > > > > > quantities with accents become identical to the corresponding ones > > > > > > > without accents; also k=1 and l=1. The components of (27) are at the > > > > > > > same time those of the electric force which is exerted by one > > > > > > > polarized particle on another." > > > > > > > > Lorentz showed that the moving observer would measure the speed of > > > > > > > light to be c in his own frame. Because of this there is no way to > > > > > > > tell if you are at rest WRT the ether. But that doesn't prevent you > > > > > > > from translating to the coordinates of another frame. If you just > > > > > > > consider yourself to be at rest WRT the ether and work it out you get > > > > > > > the same answer as you get by doing a two step translation from your > > > > > > > frame to the ether to the other frame. Assuming you are at rest WRT > > > > > > > the ether gives the same math as SR. > > > > > > > > Bruce > > > > > > > I think where I differ from Lorentz is in the 'ticking' rate of atomic > > > > > > clocks. Two frames are moving relative to one another. I think Lorentz > > > > > > is saying each Observer in a reference frame 'sees' the other > > > > > > Observer's clock as 'ticking' slower than their own. This I disagree > > > > > > with. The more at rest with respect to the aether an atomic clock is > > > > > > the faster it 'ticks'. If the embankment is at rest with respect to > > > > > > the aether and the train is moving with respect to the aether then the > > > > > > clock on the embankment 'ticks' faster than the clock on the train. > > > > > > But you don't *know* that the embankment is at rest WRT the ether.. > > > > > All you really know is how their clock syncs relate to each other due > > > > > to their relative motion. > > > > > Correct. But what about length contraction at speeds near 'c'. Won't > > > > the train moving near 'c' with its shorter measuring rod measure the > > > > train at rest with respect to the embankment to be longer and vice > > > > verse? Where the train at rest with respect to the embankment and its > > > > longer measuring rod to measure the train moving near 'c' with respect > > > > to the aether to be shorter? > > > > Good point since they claim mutual time dilation and their is no > > > prefered rest frame, how can they even claim that one object should be > > > the contracted one.... > > > > Well i asked them so many times, but their theory lack consistency > > > most paradoxes and answers is just AdHoc speculation and lack total > > > connection with reality. So i do not expect you to get an answer at > > > that question. > > > > JT > > > That's where Aether Displacement is different. In Aether Displacement > > everything is with respect to the aether. I discuss the frames of > > reference as being more, or less, at rest with respect to the aether. > > > I also like Einstein's description of the aether as, "the state of the > > [ether] is at every place determined by its connections to the matter > > and the state of the ether in neighboring places". > > > Since the aether exists through out the Earth surrounding each nuclei > > which is the matter which is the Earth, the aether at the surface of > > the Earth is at rest, or almost at rest, with respect to the surface > > of the Earth. > > > If the embankment is at rest with respect to the surface of the Earth > > and the train is moving with respect to the embankment, the embankment > > is more at rest with respect to the aether than the train is. > > > If the train is moving relative to the embankment then the frames of > > reference are not equal because they both do not exist in the same > > state with respect to the aether. > > In the above, the train and the embankment both occupy the same three > dimensional space. Think of the train as consisting of flat bed cars > which ride under the light from the lightning strikes at A/A' and B/ > B'. > > This qualification is important. At this time, I am not interested in > applying the idea of motion to the aether in terms of the embankment > having 'its own' aether and the train having 'its own' aether. If you > look at the following animation and consider water to be at rest with > respect to the embankment and water to be at rest with respect to the > train you can see what I am trying to avoid (for now at least). Look > at the light waves as the propagating through the water at rest with > respect to the embankment from A and B towards M and the light waves > propagating through the water at rest with respect to the train from > A' and B' towards M'. Ignore the waves which move from the train to > the embankment and vice verse, they are not accurate: > > http://www.youtube.com/watch?v=jyWTaXMElUk > > If the train was encased in lead and the embankment was encased in > lead would the aether be 'at rest' inside the lead encasing? At this > point, I don't know, but my guess is know. Constant momentum means > constant momentum with respect to the aether for each and every nuclei > which is the matter which is the train. > > What I have not yet been able to figure out in terms of the > terminology is how to describe constant momentum and the increase in > the aether pressure associated with increased momentum at the same > time allowing for there to be momentum. > > In other words, the faster the lead train is moving with respect to > the aether the more aether pressure there is exerted on each and every > nuclei which is the matter which is the train. But the train still has > momentum. The faster the momentum the more aether is displaced but the > more aether there is 'displacing back'. Each and every nuclei in the > lead train is not at rest with respect to the aether but the aether > does not effect the nuclei, and the trains, momentum. The aether does > not cause momentum to cease because whatever energy each and every > nuclei requires to displace the aether the aether returns to the > nuclei as it 'displaces back'. > In AD, constant momentum is aether pressure applied equally to every part of the nuclei in the matter. Acceleration is aether pressure which is not equally applied to every part of the nuclei in the matter. For example, if an object is accelerating with respect to the aether the aether is continually having to 'catch up' in terms of 'displacing back'. > > > > I still prefer Einstein's concept of "the state of the [ether] is at > > > > every place determined by its connections with the matter and the > > > > state of the ether in neighboring places" versus an 'absolutely > > > > stationary space'. > > > > > The state of the aether's displacement is at every place determined by > > > > its connections with the matter and the state of the aether in > > > > neighboring places. > > > > > Since matter and aether are different states of the same material, the > > > > aether is displaced by the matter. A moving C-60 molecule has an > > > > associated aether displacement wave. > > > > > > > The Observer on the embankment and the Observer on the train will > > > > > > arrive at the same conclusion which is the clock on the embankment > > > > > > 'ticks' faster than the clock on the train.- Hide quoted text - > > > > > > > - Show quoted text -- Dölj citerad text - > > > > > - Visa citerad text -- Dölj citerad text - > > > > > - Visa citerad text - > >
From: Ste on 22 Feb 2010 13:35 On 22 Feb, 01:04, mpalenik <markpale...(a)gmail.com> wrote: > On Feb 21, 7:53 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > On 21 Feb, 22:37, mpalenik <markpale...(a)gmail.com> wrote: > > > > On Feb 21, 4:57 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > and the authority of this group is > > > > implicitly invoked on yet another occasion. > > > > This group has no "authority" on anything whatsoever. > > > The "group" to which I was referring, and you snipped the qualifying > > clause, was "physicists as a group of people", not "this newsgroup". > > Physicists have the authority to interpret their own equations because > 1) they came up with them, so they know the principles that the > equations are derived from (whereas you have repeatedly said that > relativity is a form of correction for propagation delays which was, > first of all, not how it was derived, and second of all gives very > different predictions from what you get when you actually account for > propagation delays. The two give different predictions, therefore > they cannot be the same thing). I should clarify I was talking about *special* relativity when I talked about propagation delays, and I've yet to understand what else SR is about. > 2) Have demonstrated that their models predict actual, measured > phenomena No one disputes the data. > 3) Have spend more than a month thinking about the issues that you are > asking about But as I've said before, theologians spend their whole lives thinking about scripture. It doesn't give them authority on factual accuracy. > > > I even > > > asked PD about this a while back. For me, it's kind of theraputic, > > > after grading dozens of papers where freshman students have written > > > "no polarization" and then drawn a picture of polarized atoms, or > > > listed "the force the boy exherts on the mother is smaller than the > > > force the mother exherts on the boy" as a reason for why a mother who > > > pushes a boy on ice-skates doesn't move, while the boy does. > > > I dare say the answer to that question (although I know you weren't > > asking the question) is that the movement of each depends > > predominantly on their relative mass and the friction with the ground. > > I certainly hope these students to which you refer were high-school > > students, not university students. > > Nope, first year college freshmen. Several students, on the last test > that I graded, said that the force the mother exerts on the boy is > much greater than the force that he exerts on her. Most of them > didn't, but several did. Dear me. > > > You can't call them stupid, although here, there is no such rule when > > > someone says something so mind-bogglingly sputid. On the other hand, > > > at least, freshman physics students are capable of learning, whereas > > > for some miraculous reason, 90% of the people here seem to be stuck in > > > perpetual, unwavering ignorance. > > > Perhaps part of the reason is that students in a formal setting are > > pre-weeded for susceptibility to your teaching? > > The people taking physics 172 are from physics, chemistry (sometimes), > and engineering classes. The people taking physics 220 (physics > without calculus) are from life science courses and other non-hard- > science fields. They even have a physics without "math" for > elementary education majors. All of these people seem to be able to > learn something to varying degrees. All of them become unconfused > about at least part of the course material faster than the people in > this group. > > Do most of the people here seem to you like a random selection of > sane, well adjusted, normal people? mpc755? BURT? Androcles? Frankly no. But as I say, I would avoid drawing too many conclusions from what happens in the classroom - it is simply a fallacious appeal to both majority and authority. After all, you'd surely object if I replaced the classroom with the church, and pointed out the unanimity of opinion on the existence of God amongst the congregation.
From: mpalenik on 22 Feb 2010 13:39
On Feb 22, 1:35 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 22 Feb, 01:04, mpalenik <markpale...(a)gmail.com> wrote: > > > > > > > On Feb 21, 7:53 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > On 21 Feb, 22:37, mpalenik <markpale...(a)gmail.com> wrote: > > > > > On Feb 21, 4:57 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > and the authority of this group is > > > > > implicitly invoked on yet another occasion. > > > > > This group has no "authority" on anything whatsoever. > > > > The "group" to which I was referring, and you snipped the qualifying > > > clause, was "physicists as a group of people", not "this newsgroup". > > > Physicists have the authority to interpret their own equations because > > 1) they came up with them, so they know the principles that the > > equations are derived from (whereas you have repeatedly said that > > relativity is a form of correction for propagation delays which was, > > first of all, not how it was derived, and second of all gives very > > different predictions from what you get when you actually account for > > propagation delays. The two give different predictions, therefore > > they cannot be the same thing). > > I should clarify I was talking about *special* relativity when I > talked about propagation delays, and I've yet to understand what else > SR is about. SR *is* special relativity. That's what SR stands for. Nobody has tried to talk to you about anything else. There's no possible way that we could even hope to describe general relativity to you. All discussion so far has been about special relativity. > > > 2) Have demonstrated that their models predict actual, measured > > phenomena > > No one disputes the data. > > > 3) Have spend more than a month thinking about the issues that you are > > asking about > > But as I've said before, theologians spend their whole lives thinking > about scripture. It doesn't give them authority on factual accuracy. > They don't do testable, repeatable, verifiable experiments to validate their theological theories. They also don't have a well defined mathematical formalism to test the logical consistancy of their theological theories. > > Frankly no. But as I say, I would avoid drawing too many conclusions > from what happens in the classroom - it is simply a fallacious appeal > to both majority and authority. After all, you'd surely object if I > replaced the classroom with the church, and pointed out the unanimity > of opinion on the existence of God amongst the congregation.- Hide quoted text - Again, in the classroom, students have to be able to make falsifiable, testable, predictions, whose value is borne out by the fact that in the lab, the calculations match experiment. That's why science classes also have labs. |