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From: Inertial on 21 Oct 2009 05:03 "Jonah Thomas" <jethomas5(a)gmail.com> wrote in message news:20091020091828.45318101.jethomas5(a)gmail.com... > I'm tired of talking to you because you consistently repeat the same > biases, but once more dear friends into the breach.... > > "Inertial" <relatively(a)rest.com> wrote: >> "Jonah Thomas" <jethomas5(a)gmail.com> wrote > >> [snip] >> > I want to take this opportunity to review my understanding of >> > emission theory. >> > >> > The fundamental tenet of emission theory is that light in vacuum >> > travels at speed c relative to its source. >> >> Yes .. just like a bullet out of a gun >> >> > The reason this is important is that >> > it could possibly provide a simpler and more intuitive approach to >> > derive relativity. >> >> Relativity says the same thing. Light always travels at c relative to >> its source. >> >> However, the nature of spacetime and how velocities combine when you >> change frames of reference means that c (+) v = c (where (+) is the >> velocity composition operator). So when you 'add' the velocity of the >> source to the speed of light, you still get c. > > Yes. > >> > Light sources often appear to produce concentric waves. >> > http://i847.photobucket.com/albums/ab31/jehomas/concentric.gif >> > >> > But when they move they are thought to compress those waves. >> > http://i847.photobucket.com/albums/ab31/jehomas/eccentric.gif >> >> Thats right. >> >> Its because the emission point of each successive wavefront is not the >> same point as the previous wave front > > Yes, that's what your theory says must happen. > >> > If you could tell whether the waves were compressed then you could >> > get a handle on absolute motion. But instead special relativity (SR) >> > says that time and space are distorted so that everybody sees what >> > they ought to see. >> >> What you show in that diagram is what SR says you would see. >> >> > But if the light moved at c+v and c-v etc, >> >> If the + and - are velocity composition, then that is what SR says it >> does. >> >> > then everybody would see it >> > moving the same way without requiring time dilation and length >> > contraction. >> >> Why should everyone see the same thing? > > If the way people calculate light moving is the way the light actually > moves, then you don't need to calculate length compression and time > dilation to get them to see it that way. > >> > You might still get some time dilation etc, but some of the >> > weirdness might vanish. This is why it is an issue on >> > sci.physics.relativity. If it was only a question of precisely how >> > light works, then it would be more a question for >> > sci.physics.electromag. But since it could affect relativity, some >> > of the people who are biased against SR want emission theory to be >> > true, while the people who are biased in favor of SR categorically >> > deny any possibility that any form of emission theory could possibly >> > be true. >> >> Its not a matter of bias. > > How would you know? You're biased. > >> > The problem I run into is that it appears nobody understands >> > emission theory well enough to give a convincing argument what it >> > should do. >> >> Its not the emmission itself, what it is is that emmision theory >> assumes reality is simple euclidean goemetry, newtonian physics and >> galilean transfroms. Experiment shows reality isn't like that. > > So the next question is what is the minimum alteration to euclidean > geometry, newtonin physics and galilean transforms that would get an > emission theory to work. > >> > People often use ideas that work well when lightspeed is a constant, >> > which do not apply when lightspeed varies. >> >> The net speed light travels through a medium can be less than c, of >> course. And then the speed is observer dependant. > > Bear with me on this. > >> > For example, Androcles says that (mostly?) you cannot measure >> > wavelength. You can only measure frequency. Well, of course you can >> > measure wavelength with an interferometer. Intererence patterns >> > depend only on wavelength, not on frequency or speed. >> >> Yeup >> >> > That is, they depend only >> > on wavelength when the speed is constant. When you have light that >> > comes into the interferometer at different speeds, >> >> Why would you do that? > > If the light happens to have different speeds, that will affect the way > it interferes. Say you get light from a single source that has two > different speeds How? Emission theory says they travels always at c from the source. > going into the interferometer, each of them > self-interferes identically but the two different parts of the light > will not interfere the same way they would if they were traveling at the > same speed. > > This is your cue to say that we know light always travels at the same > speed because we have measured it with interferometers and we don't get > the interference we would expect if it was not always the same. ;) > >> > then frequency and speed do >> > matter and you cannot predict interference patterns knowing only >> > wavelength and the phase shift at the entrance. >> >> You use an interferometer on light from a known source. > > Yes, you start with light from a known laser or a known star and then > you do something to it, and then you look at the interference pattern. > That's what we're talking about. Why would you do something to it? >> > For emission theory to have a good effect on relativity, it's >> > necessary that the wavelength be the same independent of the >> > lightspeed, >> >> Which experiment shows is not the case > > Experiment shows that it's not the case provided that we understand all > about how light interferes. When you imterpret the experiments your bias > influences your thinking. So for example, you assumed you knew how > emission-theory light would interfere even when all the theory you've > ever heard about interference assumes constant lightspeed. You won't > know what emission theory predicts about interference patterns until you > actually work it out or until somebody tells you. But you assume you > already know and that it predicts the wrong thing. (And it very well > might predict the wrong thing. But you don't know, you only assume > without ever noticing the assumption.) > >> > so that >> > the light will look like >> > http://i847.photobucket.com/albums/ab31/jehomas/concentric.gif >> > instead of >> > http://i847.photobucket.com/albums/ab31/jehomas/eccentric.gif >> > If the wavelength is constant, then frequency must vary with speed. >> > So OK, your lightbeam has been split into two parts that travel at >> > different speeds. (Exactly why emission-theory light should travel >> > at different speeds in a Sagnac or Wang apparatus is one of the >> > things we don't have clear. Some people say it might not, for one >> > reason or another.) The two arrive at the detector at the same time, >> > with different speeds >> >> As measure by whom? Speed is relative to the observer. > > If two beams of light arrive at the same place and the same time at > different speeds, it isn't an issue which observer thinks they arrive at > different speeds. Yes it is. As some observers will say the speeds are the same, and some different. Unless they are travelling in the same direction. Maybe you need to draw a diagram of what you're saying? How do you split a beam so they travel at different speeds .. if they beam is split, how does it re-unite? > If you have a way to measure lightspeed and you are at > that place and time, then measure them and tell us what you get. But > don't measure them with interference until you have a solid theory how > interference patterns change with speed. the interference depends only on wavelength. You can measure the wavelength and frequency or each beam independently before they meet. > When light speeds up does the > wavelength change or the frequency or both? When the light source and detector are relatively moving, then both change as described by the SR doppler. This has been done experimentally. You seem to have a bias against experimental evidence >> In sagnac, both the beams arrive at the detector at c relative to the >> detector. According to emission theory, relative to the detector, >> they take the same time to get there, they have the same wavelength >> and the same frequency. > > How did you decide that they have the same wavelength and the same > frequency relative to the detector? From doing the math as per emmision theory > I agree that some emission theories > say that they will arrive at the same time, presumably relative to > everybody since emission theorists tend to discard relativistic > simulataneity arguments and also this is an event at one time and one > place. if you use one of these wonky emission theories where mirrors can do strange things to light speed, you can fudge a sagnac results.. but those theories are refuted by other experiments. Really .. you're wasting time on a dead theory for no reason.. SR is very simple, and supported by all the experimental evidence that has tried to refute it. >> [snip more of the same] >> >> > To construct an emission theory you must specify what light does on >> > reflection, what it does on refraction, and how interference works >> > for light that travels at different speeds. >> >> Except, of course, there are experiments that show that light from a >> moving source does not travel at c+v. Which rules out all emission >> theories. > > What assumptions were made while interpreting those experiments? Are you > sure they did nothing to assume constant lightspeed when they made their > interpretations? Look them up
From: Inertial on 21 Oct 2009 05:04 "Henry Wilson DSc." <HW@..> wrote in message news:ppdsd552vuarc6css0h91l7a9q1gusj5r7(a)4ax.com... > On Tue, 20 Oct 2009 11:32:20 +1100, "Inertial" <relatively(a)rest.com> > wrote: > >> >>"Henry Wilson DSc." <HW@..> wrote in message >>news:84spd5djv65v2hjldsqhd44nq2g72gvmi6(a)4ax.com... >>> On Tue, 20 Oct 2009 09:18:05 +1100, "Inertial" <relatively(a)rest.com> >>> wrote: >>> >>>> >>>><tominlaguna(a)yahoo.com> wrote in message >>>>news:snuod5h68j0apkqo99c4vcn4f5lhjtd456(a)4ax.com... >>>>> On Mon, 19 Oct 2009 23:03:57 +1100, "Inertial" <relatively(a)rest.com> >>>>> wrote: >>> >>>> >>>>You mean if the whole experiment does not rotate? Then in the >>>>non-rotating >>>>frame the source is at rest so the 'v' of the source is 0. c+v=c and >>>>c-v=c. >>>> >>>>When the entire device rotates, as viewed from the non-rotating frame, >>>>at >>>>the point the light is emitted the source has a velocity v. So, >>>>according >>>>to emission theory, the light travels at c+v and c-v according to a >>>>non-rotating observer. >>>> >>>>There's no magic here .. nothing special about it being light .. you'd >>>>get >>>>the same if you're talking about a gun shooting bullets in opposite >>>>directions. >>>> >>>>> the light is c relative to the source and during rotation it >>>>> is still c relative to the source. >>>> >>>>In the rotating frame .. yes .. and hence when the light arrives back at >>>>the >>>>source the two beams arrive at the same time and so with no phase >>>>difference >>>>and so no sagnac effect .. hence refuting emission theory >>> >>> hahahahhahaha! >>> >>> This gigantic blunder has become known as the 'great relativist rotating >>> frame >>> misinterpretation'. >> >>Only in your deluded little mind >> >>> You are ignoring the 'imaginary effects' that occur in rotating frames. >> >>Nope >> >>> You are >>> assuming a rotating apparatus when viewed in the rotating frame is >>> identical to >>> a nonrotating apparatus viewed in the nonrotating frame. >> >>Nope >> >>> This is hilarious....but the type of logical error one has come to >>> expect >>> from >>> relativity supporters. >> >>Nope >> >>> All you have done is demonstrate that there is no fringe displacement >>> when >>> the >>> apparatus does not rotate. >> >>And according to emission theories, none when it DOES rotate, because the >>beams arrive at the detector with the same speed relative to the detector, >>and the same frequency as measured at the detector, and so therefore with >>no >>phase difference. > > You simply cannot get into your head the fact that light does not involve > conventional oscillators and waves. You have no mind.
From: Inertial on 21 Oct 2009 05:04 "doug" <xx(a)xx.com> wrote in message news:M4ednTDYWNeYp0PXnZ2dnUVZ_t-dnZ2d(a)posted.docknet... > > > Henry Wilson DSc wrote: >> On Tue, 20 Oct 2009 11:32:20 +1100, "Inertial" <relatively(a)rest.com> >> wrote: >> >> >>>"Henry Wilson DSc." <HW@..> wrote in message >>>news:84spd5djv65v2hjldsqhd44nq2g72gvmi6(a)4ax.com... >>> >>>>On Tue, 20 Oct 2009 09:18:05 +1100, "Inertial" <relatively(a)rest.com> >>>>wrote: >>>> >>>> >>>>><tominlaguna(a)yahoo.com> wrote in message >>>>>news:snuod5h68j0apkqo99c4vcn4f5lhjtd456(a)4ax.com... >>>>> >>>>>>On Mon, 19 Oct 2009 23:03:57 +1100, "Inertial" <relatively(a)rest.com> >>>>>>wrote: >>>> >>>>>You mean if the whole experiment does not rotate? Then in the >>>>>non-rotating >>>>>frame the source is at rest so the 'v' of the source is 0. c+v=c and >>>>>c-v=c. >>>>> >>>>>When the entire device rotates, as viewed from the non-rotating frame, >>>>>at >>>>>the point the light is emitted the source has a velocity v. So, >>>>>according >>>>>to emission theory, the light travels at c+v and c-v according to a >>>>>non-rotating observer. >>>>> >>>>>There's no magic here .. nothing special about it being light .. you'd >>>>>get >>>>>the same if you're talking about a gun shooting bullets in opposite >>>>>directions. >>>>> >>>>> >>>>>>the light is c relative to the source and during rotation it >>>>>>is still c relative to the source. >>>>> >>>>>In the rotating frame .. yes .. and hence when the light arrives back >>>>>at the >>>>>source the two beams arrive at the same time and so with no phase >>>>>difference >>>>>and so no sagnac effect .. hence refuting emission theory >>>> >>>>hahahahhahaha! >>>> >>>>This gigantic blunder has become known as the 'great relativist rotating >>>>frame >>>>misinterpretation'. >>> >>>Only in your deluded little mind >>> >>> >>>>You are ignoring the 'imaginary effects' that occur in rotating frames. >>> >>>Nope >>> >>> >>>>You are >>>>assuming a rotating apparatus when viewed in the rotating frame is >>>>identical to >>>>a nonrotating apparatus viewed in the nonrotating frame. >>> >>>Nope >>> >>> >>>>This is hilarious....but the type of logical error one has come to >>>>expect from >>>>relativity supporters. >>> >>>Nope >>> >>> >>>>All you have done is demonstrate that there is no fringe displacement >>>>when the >>>>apparatus does not rotate. >>> >>>And according to emission theories, none when it DOES rotate, because the >>>beams arrive at the detector with the same speed relative to the >>>detector, and the same frequency as measured at the detector, and so >>>therefore with no phase difference. >> >> >> You simply cannot get into your head the fact that light does not involve >> conventional oscillators and waves. > > Well, ralph, you are wrong again. This has been known for over a > century. You should look up some more recent science and then > you will not look so stupid. Do you really think that would help him?
From: Inertial on 21 Oct 2009 07:38 "Henry Wilson DSc." <HW@..> wrote in message news:39ntd5trtocg8mk3p4fhsntn8hmvm0v6g9(a)4ax.com... > On Wed, 21 Oct 2009 20:04:14 +1100, "Inertial" <relatively(a)rest.com> > wrote: > >> >>"Henry Wilson DSc." <HW@..> wrote in message >>news:ppdsd552vuarc6css0h91l7a9q1gusj5r7(a)4ax.com... >>> On Tue, 20 Oct 2009 11:32:20 +1100, "Inertial" <relatively(a)rest.com> >>> wrote: >>> >>>> >>>>"Henry Wilson DSc." <HW@..> wrote in message >>>>news:84spd5djv65v2hjldsqhd44nq2g72gvmi6(a)4ax.com... >>>>> On Tue, 20 Oct 2009 09:18:05 +1100, "Inertial" <relatively(a)rest.com> >>>>> wrote: >>>>> >>>>>> >>>>>><tominlaguna(a)yahoo.com> wrote in message >>>>>>news:snuod5h68j0apkqo99c4vcn4f5lhjtd456(a)4ax.com... >>>>>>> On Mon, 19 Oct 2009 23:03:57 +1100, "Inertial" <relatively(a)rest.com> >>>>>>> wrote: >>>>> >>>>>> >>>>>>You mean if the whole experiment does not rotate? Then in the >>>>>>non-rotating >>>>>>frame the source is at rest so the 'v' of the source is 0. c+v=c and >>>>>>c-v=c. >>>>>> >>>>>>When the entire device rotates, as viewed from the non-rotating frame, >>>>>>at >>>>>>the point the light is emitted the source has a velocity v. So, >>>>>>according >>>>>>to emission theory, the light travels at c+v and c-v according to a >>>>>>non-rotating observer. >>>>>> >>>>>>There's no magic here .. nothing special about it being light .. you'd >>>>>>get >>>>>>the same if you're talking about a gun shooting bullets in opposite >>>>>>directions. >>>>>> >>>>>>> the light is c relative to the source and during rotation it >>>>>>> is still c relative to the source. >>>>>> >>>>>>In the rotating frame .. yes .. and hence when the light arrives back >>>>>>at >>>>>>the >>>>>>source the two beams arrive at the same time and so with no phase >>>>>>difference >>>>>>and so no sagnac effect .. hence refuting emission theory >>>>> >>>>> hahahahhahaha! >>>>> >>>>> This gigantic blunder has become known as the 'great relativist >>>>> rotating >>>>> frame >>>>> misinterpretation'. >>>> >>>>Only in your deluded little mind >>>> >>>>> You are ignoring the 'imaginary effects' that occur in rotating >>>>> frames. >>>> >>>>Nope >>>> >>>>> You are >>>>> assuming a rotating apparatus when viewed in the rotating frame is >>>>> identical to >>>>> a nonrotating apparatus viewed in the nonrotating frame. >>>> >>>>Nope >>>> >>>>> This is hilarious....but the type of logical error one has come to >>>>> expect >>>>> from >>>>> relativity supporters. >>>> >>>>Nope >>>> >>>>> All you have done is demonstrate that there is no fringe displacement >>>>> when >>>>> the >>>>> apparatus does not rotate. >>>> >>>>And according to emission theories, none when it DOES rotate, because >>>>the >>>>beams arrive at the detector with the same speed relative to the >>>>detector, >>>>and the same frequency as measured at the detector, and so therefore >>>>with >>>>no >>>>phase difference. >>> >>> You simply cannot get into your head the fact that light does not >>> involve >>> conventional oscillators and waves. >> >>You have no mind. > > You have a typical logic impaired female mind. You don't recognise logic when you see it, nor the flaws in what you think is your own. Interesting that you use 'female' as an insult.
From: Darwin123 on 21 Oct 2009 11:11
On Oct 19, 8:13 pm, Jonah Thomas <jethom...(a)gmail.com> wrote: > Darwin123 <drosen0...(a)yahoo.com> wrote: > > Charles Ives was a physicist who strongly disblieved in general > > relativity.... > > Charles Ives described a thought experiment to show why the > > Sagnac effect contradicted relativity. However, the symmetry that he hypothesized did not exist in > > the equivalent real-world systme. > > He proposed a Sagnac interferometer consisting of a highly > > reflective ring of material. There would not be separate mirror, but a > > continuous curve of reflective material. He proposed that the ring was > > completely circular, so that the optical system had complete radial > > symmetry. A rotation by any angle would not change the system, in his > > model, by any amount. Suppose two traveling waves are propagating in > > opposite directions in this circular cavity. > > His argument was that since the cavity is radially symmetric, > > there is no way the light waves can "know" that the cavity was > > rotating. The surface of this smooth cavity is smooth and featureless. > > Motion can not show itself on a featureless surface. Thus there could > > be no beats between the two waves, and thus no Sagnac effect. Since > > the Saganc effect is predicted by relativity, the fact there is no > > Sagnac effect for such a cavity means relativity is wrong. > > Note he didn't make the main error provided by members of the > > group. He did not claim the Saganc effect contradicts relativity. His > > arguement was that the Sagnac effect couldn't exist under certain > > conditions that were consistent with relativity. > > First, let me point out that such a system has been made.. > > Sagnac cavities have been constructed using fibers connected in a > > circle. There are no separate mirrors in such a cavity. The reflective > > surface is a continuous curve. The Sagnac effect has been observed > > with such continuously curved surfaces. So what went wrong with Ives' > > analysis? > > If the emitter and the detector move with the mirror, which they had > probably better do, then you get a Sagnac effect because they are > moving. I believe you could get a sagnac effect with the source and > detector moving even if they were bouncing light off mirrors that did > not move. But like Ives I have not done the experiment. > > > 1) The cavity, though "continuously curved," is made of atoms. Thus, > > it did break down. > > 2) The free electrons on the surface, that cause the reflection of > > light, are also discrete up to the limits of quantum mechanics. > > 3) The light itself consists of nodes and antinodes. Thus, the > > illuminated surface is not flat and featureless. There are regions > > with oscillating electrons, and these are forced to rotate by the > > elastic forces in the cavity. > > I doubt all that matters. Get your detector and emitter moving along the > mirror cylinder and you'll get a Sagnac effect with the mirror not > moving at all. If it doesn't matter whether the mirror moves then it > does not matter abouut the astoms and the free electrons and the > antinodes. > It only matters when analyzing systems that seem "featureless" on a macroscopic level. Herbert Ives tried debunk relativity by hypothesizing a resonanat cavity whose surface was featureless because it was so smooth. His "thought experiment" analyzed a hypothetical system with complete rotational symmetry. Thus, he arguing against Lorentz invariance by claiming that it violated rotational symmetry. Complete rotational symmetry is not valid for any system on an atomic scale of distance. Lorentz invariance is valid on both atomic scales and macroscopic scales. Thus, the system Ives discussed is not physical even as a limiting case. Therefore, the thought experiment of Ives is invalid. Ives argument is like claiming that electric currents can't exist in a perfectly homogenous piece of metal. In order to have an electric current, the charge desnsity has to be a little "lumpy." There have to be either discrete electrical charges that are free to move, or waves with nodes and antinodes. The nodes and antinodes have to be free to move. There is an effect in Sagnac cavities where the nodes and the antinodes are locked in place by hysteresis in the metal reflectors. The Sagnac effect vanishes when this happens. I read an article describing what causes it and how to remediate it. This is a material property, and is considered a defect in the apparatus. If metals didn't have hysteresis type properties, it wouldn't happen. However, hysteresis is a macroscopic property not atomic. The closest approach to building such a system has been constructed using fiber optics. The fibers don't have hysteresis (as far as I know), and the surface is as smooth as technology can make it. However, the atoms in the optical fiber still make the surface "lumpy" on an atomic scale. Thus, it still isn't smooth enough to satisfy the requirements for Ives cavity. I hypothesize that there is not system that even approaches the smoothness required by Ives analysis. Thus, his argument against relativity is invalid. |