Wang / Sagnac Devices
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From: Androcles on 23 Oct 2009 11:27 <tominlaguna(a)yahoo.com> wrote in message news:01f3e5lnslv9h9svdacptkvi2vsr00b067(a)4ax.com... > On Fri, 23 Oct 2009 12:20:32 +0000 (UTC), bz > <bz+spr(a)ch100-5.chem.lsu.edu> wrote: > >>tominlaguna(a)yahoo.com wrote in >>news:8qm2e594ha17fniorfc2fjktli1n1f03b3(a)4ax.com: >> >>> On Fri, 23 Oct 2009 02:32:10 +0000 (UTC), bz >>> <bz+mspep(a)ch100-5.chem.lsu.edu> wrote: >>> >>>>tominlaguna(a)yahoo.com wrote in news:bqs0e5lqmuqtjqft1lvurh8ui21i974qp0@ >>>>4ax.com: >>>> >>>>> Almost correct. For example, in the situation where a mirror is >>>>> moving normally toward a source at velocity v, the mirror will >>>>> experience the light as arriving at c + v. Upon reflection, the light >>>>> will be traveling at c + 2v with respect to the source; and, as you >>>>> state, at c + v with respect to the mirror. >>>> >>>>Easily tested by experiment: >>>>a) Two parallel mirrors, moving toward and away from each other (one >>>>attached to the voice coil of a loud speaker, or plated onto a surface >>>>of a quartz crystal). >>>>b) laser beam bouncing back and forth between the mirrors many times. >>>>If the bounce is n times, then the final velocity of the light exiting >>>>from the pair of mirrors should >>>>be c+n*v and c-n*v >>> >>> That is a very interesting concept. I will try to model it and see if >>> it can be done easily. I am thinking the result might be c+/-2n*v. >> >>Correct, if both mirrors are moving, toward or away from each other. >>Then they would have a peak 'closing speed' of +/- 2v. >>I was only thinking of moving one of them but my wording was ambiguous. > > What type of detection system would you suggest? Androcles put up a > .gif of a Crooks radiometer which might work. Though, it would be > nice to have a more accurate radiometer like the Nichols design. I > don't know if anything like that exists commercially. I was thinking > of using a prism as the detector to display changes in the refraction > angle. By having the prism near the mirrors and the viewing screen at > some distance, one might be able to register minute angular > differences. Your thoughts are welcome. The radiometer was to provide a vacuum, nothing more. The light accelerator is here, http://www.androcles01.pwp.blueyonder.co.uk/Wave/lightaccel.gif Each wing or paddle is a suitably balanced vane on a rotating shaft and if you look carefully you'll see the light climbs with each reflection, so it can be repeated. The mirrors are parallel as required, although they can be very narrow and close together. Engineering of DVD quality would be needed, so it's not a shed or garage project.
From: Tom Roberts on 23 Oct 2009 13:25 tominlaguna(a)yahoo.com wrote: > [...] You forgot to say in which frame you are discussing this. I'll discuss both the "rotating frame" and the inertial frame of the lab, in which the center of the interferometer is at rest. I put "rotating frame" in quotes, because it simply is not possible to construct the usual coordinate frame in a rotating system. It can be done only approximately, and the approximation is not accurate enough for the analysis of a Sagnac interferometer. Note that no theory of interest, ballistic, aether, or SR, is expressed in a rotating system -- ALL of them inherently use inertial coordinates. So if you were using a "rotating frame", you cannot make any statements about any of those theories, without referring to some inertial frame (and you don't). I also assume you are ignoring the air. > 1. Light is emitted from source O at c with respect to that source. Wrong. Lab: the platform is ROTATING (and O is not at the center). Rotating: the light INITIALLY moves at speed c relative to O, but that is no longer true when the light changes radius, as it clearly does in the figure. Nor does it move at speed c relative to the rotating coordinates. This is one of the problems with trying to use a "rotating frame" -- light does NOT propagate with constant speed relative to rotating coordinates. This is easy to verify as long as you remember that in vacuum the light moves at c relative to the source WHEN MEASURED IN THE INERTIAL FRAME OF THE LAB. 1a. You omitted a description of the light passing through N, whatever that is. > 2. The light arrives at and is reflected off mirror m at speed c since > there is no "line-of-sight" relative motion between m and O. Wrong. The mirror has nonzero velocity relative to O -- their velocity vectors are not parallel (due to the rotation of the platform). Any two objects on the platform have different velocity vectors, except for the case where they occupy the same place (in which case they are not really two objects). Lab: The mirror has nonzero velocity relative to the lab, and neither the incident nor reflected beam is orthogonal to it. Rotating: O and m appear to be at the same radius so they have no relative motion in the "rotating frame", but you do not know how light reflects from a mirror in a "rotating frame" -- ballistic theory does not discuss it, and it's clear that Snell's law does not hold. > [... many similar mistakes] I repeat: to analyze how light reflects from a mirror, you really need to use the inertial frame in which the mirror is at rest when the light reflects from it -- you don't know what happens for any other case (and it is theory dependent). This means that for a mirror on a rotating platform one must analyze a short light pulse, not a continuous beam. Tom Roberts
From: Jonah Thomas on 23 Oct 2009 16:01 bz <bz+spr(a)ch100-5.chem.lsu.edu> wrote: > tominlaguna(a)yahoo.com wrote > > bz <bz+spr(a)ch100-5.chem.lsu.edu> wrote > >>tominlaguna(a)yahoo.com wrote > >>> tominlaguna(a)yahoo.com wrote: > > >>> [snip] > .... > >>> 18. Beam T arrives at telescope L at c since there is no > >>> "line-of-sight" relative motion between mirror j and telescope L. > >>> 19. Beam T proceeds down the telescope and arrives at the > >photographic>> plate PP' at speed c since there is no "line-of-sight" > >relative motion>> between telescope L and the film at PP'. > >>> 20. The diagram properly shows that counter-clockwise beam R > >arrives>> before the clockwise beam T since it has traversed a > >shorter optical>> path length; made shorter due to rotation. > >> > >>You just jumped from the rotating frame of reference "along the > >'line-of->sight'" to the fixed frame of reference, which is the frame > >in which the >distances traveled are different. > >>Naughty, naughty! Suppose we stay with one frame, the inertial frame. Is there any reason for a simple emission theory to claim that the light speed would be different in the two directions? Ritz says maybe, it depends on the direction that the original light source was pointing. If the original light pointed opposite to the direction of rotation (as in the original Sagnac design) then yes. If it pointed toward the center or outward, then no. In the fiber optic laser cavity, yes. Since the Sagnac result appears to be pretty much unchanged in all those cases, Ritz emission theory would need two different explanations to get the same result in the different cases. If light takes up the speed of the mirror on each reflection, then the speed will be different in the two directions, and a different explanation is needed. But Tominlaguna's Ballistic theory says that does not happen. But if all the light travels at c-v from the time of its emission, then all the examples with the mirrors will have light travel the same constant speed and the same explanation that works for other theories works for that emission theory. The exception is the laser cavity, in that case the light ought to travel at c+v and c-v and a different explanation is needed. > >>The path lengths do NOT change as measured along the 'line-of-sight' > > > >>distances traveled in the rotating frame of reference, so unless you > >have >some magic Wilsonian effect to insert, you seem to be out of > >luck. > > >>In the rotating frame of reference, in the ballistic theory, the > >_only_ >place that you can look for any difference between rotating > >and non >rotating saganac apparatus is the coriolis effect, and if I > >remember >correctly, that is insufficient in magnitude to account for > >the observed >saganac effects. Coriolis effect is the only possibility, and you know it is insufficient? You have light suffering angular acceleration. How do you know what that will do to light? Incidentally, you can get fiber optic cable that enforces a particular polarization, or slower fiber optic cable which does not. Could you lay down the polarizing cable so the light has to be polarized parallel or perpendicular to the plane of the Sagnac experiment? Could you polarize the light each way for the thicker cable? Would that make any difference? > >>> 21. The reader can reconstruct the path steps in a similar manner > >for>> the counter-clockwise beam. > >>> > >>> Summarizing: > >>> > >>> A. The Ballistic Theory of Light has 2 Postulates: (1) Light is > >>> emitted at c with respect to its source and (2) light is reflected > >a c>> with respect to the mirror image of the source. > >>> B. With the Ballistic Theory of Light, the beams of light > >traverse>> the optical circuit at speed c in each direction since > >there is no>> "line-of-sight" relative motion element-to-element. > >> > >>AND no change in distance traveled along that line of sight. I am concerned that emission theories have two cases, one with a single light source and one with a laser cavity that emits light in two opposite directions. Most emission theories should treat those two cases differently, and some special explanation is needed for the second case. Other theories need only one explanation. But it's early to say there can be no second explanation. > >>> C. The angle of incidence equals the angle of reflection at all > >>> points of reflection. > >>> D. The counter-clockwise beam arrives sooner than the opposing > >beam>> because it has a shorter optical path length to traverse. > >> > >>bzzzt. wrong! When you start with a single light source, there is no reason for Tominlaguna's Ballistic theory to have different lightspeeds. So it's just like the classical or relativistic cases. When you start with a laser cavity it looks like you're giving up emission theory if you make the light speeds the same in the inertial frame. That case needs a new explanation. > >>> E. The Ballistic Theory of Light is compatible with the Sagnac > >>> experiment. > >> > >>Sorry but you seem to be wrong. > > > > Rather than replying to each criticism at this time, what if I > > adopted the Mathpages version and said my "closing speed" in one > > direction is c+v and it is c-v in the opposite direction? Would > > that make it more palatable? I doubt it. Your debating partner has probably decided ahead of time that Sagnac proves all emission theories wrong, and so he will continue to believe that regardless. > In that case, you are measuring everything from the fixed frame of > reference and the path lengths DO change. > It so happens that when you work out the math and calculate the TIME > of flight over those different length paths at those 'closing speeds', > you will come up with identical time of flight for both the clockwise > and counterclockwise propagation, for the ballistic theory. I think you are right for the case of a laser cavity, and wrong in all other cases. > Thus predicting no saganac effect, which is falsified by experimental > data. Thus requiring one complication, one step down the slippery slope of patched theories.
From: Jonah Thomas on 23 Oct 2009 16:10 doug <xx(a)xx.com> wrote: > Jonah Thomas wrote: > > doug <xx(a)xx.com> wrote: > >>Jonah Thomas wrote: > > > >>>When I started to pay attention to problems in Einstein's original > >>>paper various people pointed me to a later Einstein paper which > >they>>said was better written and which cleared things up. If we've > >had a>>hundred years to learn better how to derive SR and how to > >teach it,>>and we are no better than Einstein in 1920, then something > >is very>>wrong. > >>> > >>>In the last hundred years explanations have been found for the > >>>various self-contradictions and failures of SR, so the problems > >have>>either been fixed or covered over. > >> > >>There are no contradictions or failures of SR in its domain of > >>applicability. There was nothing to fix. > >> > >> There's no need to pretent there were never any > >> problems if the problems have been resolved. > >> > >>Point out a problem is you think there was one? > > > > To you? Whatever for? You would deny it and argue that it never > > existed, you would misunderstand and confuse the issue. I have > > better things to do than argue with fanatics. > > > So you have no problems to point out. I just wanted you to be clear > on that. Believe whatever you want. You will anyway. You are a fanatic who has chosen what to believe and is not open to new information. It would be silly for me to argue with you.
From: Jonah Thomas on 23 Oct 2009 16:31
Tom Roberts <tjrob137(a)sbcglobal.net> wrote: > tominlaguna(a)yahoo.com wrote: > I repeat: to analyze how light reflects from a mirror, you really need > to use the inertial frame in which the mirror is at rest when the > light reflects from it -- you don't know what happens for any other > case (and it is theory dependent). This means that for a mirror on a > rotating platform one must analyze a short light pulse, not a > continuous beam. Interesting thought! Light travels through a fiber optic cable at about 200,000 km/sec. So if you could do the Sagnac or Wang experiment with 2000 km of cable, you could get a time delay of about 0.01 second. Spin your spool of cable fast enough and you could see whether a short laser pulse arrives at the same time. It's no problem to get a spool with 1 km of cable. That gives you 5*10^-6 seconds. How fast can you spin it? How short a laser pulse can you put through it? |