Speed of Light: A universal Constant?
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From: Henri Wilson on 28 Mar 2005 18:38 On Mon, 28 Mar 2005 11:52:28 +0100, "George Dishman" <george(a)briar.demon.co.uk> wrote: > >"Henri Wilson" <H@..> wrote in message >news:hlie41lsobbs9jnn3l8ai3g08pi2e0se0o(a)4ax.com... >> On Sat, 26 Mar 2005 00:10:05 -0000, "George Dishman" >> <george(a)briar.demon.co.uk> >> wrote: >> >>> >>>"Henri Wilson" <H@..> wrote in message >> >>> >>>>>As we have discussed before, ballistic theory is >>>>>disproved by the Sagnac Experiment. >>>> >>>> Bull. The reason for the fringe shift has nothing to do with light >>>> speed. >>>> It is due to the fact that the mirrors rotate slightly during the time >>>> light >>>> travels between them. The two opposite beams are deflected in opposite >>>> directions. >>> >>>We went over that last time. You got the >>>geometry wrong, the beams are deflected >>>such that they maintain the angle between >>>them at the interferometer. >> >> No they don't. >> Just draw a simple diagram. > >Here's the one I drew a year ago: > >http://www.briar.demon.co.uk/Henri/lab.gif > >I have added a small indicator showing where >the rotation maintains the 90 degree angle >at the detector in the four-mirror case. > >Note also any change of angle would alter the >gap between the fringes and not produce a >lateral shift. Look, the reason fringes are observed at all is pretty complicated. If the apparatus is properly set up and not rotating, a series of circular fringes will be observed through the eyepiece. They appear as a result of viewing angle differences. If the two interferometer beams are deflected sideways in opposite directions and end up with a small angular difference because of apparatus rotation, then then I believe the fringes will be seen to move. > >> The angular deflection of the beam at each miror is double the angular >> change >> of the mirror during the travel time. > >Correct for each beam, but it is in the same >direction for the two beams so cancels. NO!!!! It is in the opposite direction for each beam. > >> For three mirrors, the total angular difference is 16 x rotation during >> total >> light travel time. >> >> Like I said, whether c or c+v is used is of little consequence. > >On the contrary, since the detector is sensitive >to the time difference and not the angle between >the beams, speed is the critical factor. I agree the detector WOULD BE sensitive to time differences but it is rotatiopn that we are interested in. I say the fringe movement effect would be the same if light speed was 0.5c. > >> Don't use the rotating frame. There is too much room for >> misinterpretation. > >True, we need to be careful, but here is the >same drawing as above in the rotating frame. > >http://www.briar.demon.co.uk/Henri/paths.gif > >It produces the same conclusion. But you are basing this on the incorrect conclusion that the deflections are in the same direction and cancel. That is wrong. The beams never meet again at any of the mirrors. > ><snip> >>>... show your >>>calculations if you think you can explain >>>how the first order output arises. >> >> Let the light travel time around the four mirror system be 10 ns. >> >> An apparatus rotation of (2pi/3600) radians/hour (0.1 deg/hr) should >> result in >> a deflection difference between the two beams of 12 x 3 (m) x 10/3600/10^8 >> metres/sec. >> >> That is 10^-9 m/sec. >> >> or 0.001 um. >> >> ~ 500 x wavelength? >> >> How wide is a fringe? > >You seem to be calculating the lateral shift of >the beam but that is parallel to the wavefront >so has no effect on the fringe pattern or the >brightness at the centre. I don't agree.. for the reasons I gave above. If what you say is correct, there would be no fringes, just black or white. It is the angle subtended by the light entering the eyepiece that matters. > >The relative brightness at any point is a measure >of the phase difference between the beams so you >need to find the difference in propagation time >as a fraction of the period (1/frequency of >course). ..and like I said, if that were true, you would get no fringes but a uniform light intensity across the whole viewing area. > >Referring to this: >http://www.briar.demon.co.uk/Henri/lab.gif > >It should be obvious that the red path for the >co-rotating beam is longer than the green path >for the counter-rotating beam. If the speed is >c in the lab frame, that length difference >produces exactly the output observed while if >it is c+v for the red beam and c-v for the green >beam, the speed difference exactly cancels the >path length difference so the propagation time >for the two beams is identical meaning no output >for the Ritzian model. > >Let me turn that around - if you measure the >difference in propagation time and you know the >speed of the table, you can calculate the speed >of the beams. That answer is c in the lab frame >regardless of the speed of the table even though >the source, the detector and the mirrors (or the >fibre in the case of an iFOG) are all moving. >The experiment measures the speed of light from >a moving source and the observed result is c, >not c+v. But your diagram is wrong. The beams never meet again at any mirror. > >George > HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong.
From: Henri Wilson on 28 Mar 2005 18:42 On Mon, 28 Mar 2005 14:11:23 GMT, Sam Wormley <swormley1(a)mchsi.com> wrote: >Henri Wilson wrote: > >> However nobody has ever measured the OW light speed from a moving source. >> > >Henri Wilson forgets that the speed of light is a *defined* constant > http://scienceworld.wolfram.com/physics/SpeedofLight.html > >And that that the constancy of the speed of light (even one way) is constantly being >verified by the global positioning system (GPS) 24/7--Moving sources, Henri! > >And historically there is a body of OWLS experiments >Ref: http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html#one-way%20tests > >3.2 One-Way Tests of Light-Speed Isotropy > Note that while these experiments clearly use a one-way light path > and find isotropy, they are inherently unable to rule out a large > class of theories in which the one-way speed of light is > anisotropic.These theories share the property that the round-trip > speed of light is isotropic in any inertial frame, but the one-way > speed is isotropic only in an ether frame. In all of these theories > the effects of slow clock transport exactly offset the effects of the > anisotropic one-way speed of light (in any inertial frame), and all > are experimentally indistinguishable from SR. All of these theories > predict null results for these experiments. See Test Theories above, > especially Zhang (in which these theories are called "Edwards > frames"). > >Cialdea, Lett. Nuovo Cimento 4 (1972), p821. > Uses two multi-mode lasers mounted on a rotating table to look for > variations in their interference pattern as the table is rotated. > Places an upper limit on any one-way anisotropy of 0.9 m/s. > >Krisher et al., Phys. Rev. D, 42, No. 2, pp. 731-734, (1990). > Uses two hydrogen masers fixed to the earth and separated by a 21 km > fiber-optic link to look for variations in the phase between them. > They put an upper limit on the one-way linear anisotropy of 100 m/s. > >Champeny et al, Phys. Lett. 7 (1963), p241. > >Champeney, Isaak and Khan, Proc. Physical Soc. 85, p583 (1965). > >Isaak et al, Phys. Bull. 21 (1970), p255. > Uses a rotating Moessbauer absorber and fixed detector to place an > upper limit on any one-way anisotropy of 3 m/s. [one part in 10^8] Sam, it is true that OWLS is 100% isotropic when all parts of the measuring apparatus are mutually at rest. That is what the ballistic theory expects. HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong.
From: Henri Wilson on 28 Mar 2005 18:43 On 28 Mar 2005 02:21:33 -0800, "Jerry" <Cephalobus_alienus(a)comcast.net> wrote: >Henri Wilson wrote: > >> Wormley, it is true according to the ballistic theory that TWLS >> experiments DO reveal the true value of OW light speed between >> objects mutually at rest. It is indeed 'c'. >> >> I gather you are agreeing with this. >> >> However nobody has ever measured the OW light speed from a >> moving source. > >False. > >One-way light speed from moving sources has been measured many >times. The results are quite unambiguous. The speed is always c. > >Alvaeger, Farley, Kjellman and Wallin, > Physics Letters 12, 260 (1964) > >Babcock and Bergmann, > Journal Opt. Soc. Amer. Vol. 54, p. 147 (1964) > >Beckmann and Mandies, > Radio. Sci. 69D (1965), p623. > >Brecher, > Phys. Rev. Lett. 39 1051-1054, 1236(E) (1977) > >Filipas and Fox, > Phys. Rev. 135, 1071 B (1964) > >Sadeh, > Phys. Rev. Lett. 10 no. 7 (1963) > >Google search shows that the above references have been provided >to you, or on threads known to be read by you, multiple times. You >have never bothered to look them up, and have always discounted >their unambigous message without having read them. None of them is a direct measurement of OWLS from a moving source. > >Jerry's big brother > >P.S. Jerry is a gender-neutral name. About 20% of all Jerrys are >female. (For example, supermodel/actress Jerry Hall) >My sister's real name is also gender neutral. HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong.
From: Jerry on 28 Mar 2005 18:56 Henri Wilson wrote: > On 28 Mar 2005 02:21:33 -0800, "Jerry" <Cephalobus_alienus(a)comcast.net> wrote: > > >Henri Wilson wrote: > > > >> Wormley, it is true according to the ballistic theory that TWLS > >> experiments DO reveal the true value of OW light speed between > >> objects mutually at rest. It is indeed 'c'. > >> > >> I gather you are agreeing with this. > >> > >> However nobody has ever measured the OW light speed from a > >> moving source. > > > >False. > > > >One-way light speed from moving sources has been measured many > >times. The results are quite unambiguous. The speed is always c. > > > >Alvaeger, Farley, Kjellman and Wallin, > > Physics Letters 12, 260 (1964) > > > >Babcock and Bergmann, > > Journal Opt. Soc. Amer. Vol. 54, p. 147 (1964) > > > >Beckmann and Mandies, > > Radio. Sci. 69D (1965), p623. > > > >Brecher, > > Phys. Rev. Lett. 39 1051-1054, 1236(E) (1977) > > > >Filipas and Fox, > > Phys. Rev. 135, 1071 B (1964) > > > >Sadeh, > > Phys. Rev. Lett. 10 no. 7 (1963) > > > >Google search shows that the above references have been provided > >to you, or on threads known to be read by you, multiple times. You > >have never bothered to look them up, and have always discounted > >their unambigous message without having read them. > > None of them is a direct measurement of OWLS from a moving source. False. Obviously you've not read a single one of them. Jerry's older brother
From: Henri Wilson on 28 Mar 2005 18:57
On Mon, 28 Mar 2005 10:59:57 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >H@..(Henri Wilson) wrote in >news:4hgf4152vbnmi93d0aqd2adk72u1qevbab(a)4ax.com: > >> On Mon, 28 Mar 2005 02:54:28 +0000 (UTC), bz >> <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >> >>>H@..(Henri Wilson) wrote in >>>news:i9ke41pi6c62gfr6mkb14efoeher4odrg4(a)4ax.com: >>> >>>> On Sat, 26 Mar 2005 01:36:41 +0000 (UTC), bz >>>> <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >>>> >> >>>>>because photons always travel at the speed of light, which is >>>>>constant. >>>> >>>> There is no such animal as 'speed of light' or 'speed of anything' for >>>> that matter. Speed must be specified relative to something else. >>> >>>Light travels at c relative to any observer. >> >> Who said? > >The data. > >http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html#one-wa >y%20tests [quote] >as of this writing there are no reproducible and generally-accepted >experiments that are inconsistent with SR, within its domain of >applicability. [unquote] >The author has reviewed many experiments. > >> >>> >>>>>>>Why, when we measure the speed of those photons, do the photons seem >>>>>>>to move at the same speed? >>>>>> >>>>>> Silly boy. Nobody has measured the OW speed of light under any >>>>>> circumstance. >>>>> >>>>>Define 'one way speed of light'. >>> >>>You still haven't defined the 'one way speed of light'. >> >> listen bz, read up on this before you make an even bigger fool of >> yourself. > >I am not the one that said: >>>>>> Silly boy. Nobody has measured the OW speed of light under any >>>>>> circumstance. > >How do YOU define 'one way speed of light'? It must be different from the >way others do because MANY experiments have measured something called 'one >way speed of light' but it must be different from your definition. I >wanted yours. The OW speed of ligght has been inferred from TW light speed experiments, which produce the answer 'c'. In actual fact, it this correct when all parts of the measuring apparatus are at rest. In such cases, according top the ballistic theory, TWLS=OWLS. > >> >>> >>>>>I fire a laser pulse at two detectors, 1 at 1 meter and 1 at 10 meters >>>>>from the laser. I have a timer located mid way between the two >>>>>detectors. >>>>> >>>>>When the pulse hits the first detector, it starts the timer >>>>>When the pulse hits the second detector, it stops the timer. >>>>> >>>>>Taking into account all the propagation delays, I calculate the time >>>>>that it took the light pulse to travel between detector 1 and detector >>>>>2. >>>>> >>>>>Why is this not the 'one way speed of light'??? >>>> >>>> Ask any of your SRian colleagues. >>> >>>I ask you because you made the claim that the doppler effect was due to >>>changes in speed of light rather than changes in wavelength. >> >> It can be. 'Frequency' of an EM signal is the number of wavecrests >> passing per second. Naturally, that is dependent on observer speed >> relative to the source. >> > >Frequency is not velocity. I can measure the frequency AND the velocity. >When I do, I find the frequency has shifted, but not the velocity. Sorry, you cannot measure the velocity of an EM wave relative to yourself. There is no known way. > >> >> ..but please recall that I have raised the question about how a >> diffraction grating can measure doppler shifted light. > >Do you understand how a diffraction grating works on non doppler shifted >light? It works the same on doppler shifted light. That's what I said. It is a function of wavelength only. So what might 'wavelength' refer to in the case of an individual photon? > >> >>> >>>> >>>> Clue: How do you synchronize the separated clocks? >>> >>>In my experiment there is no need for separated clocks. >> >> You have two separated clocks but haven't realized it. > >show me. Why don't you ask your relativity expert, Tom Roberts. >>> >>>The claim that the effect will only work in a pure vacuum is similar. It >>>means the effect will never be observed. >> >> I say there is a critical density of matter, below which all kinds of >> strange things happen. > >Does that critical density occur anywhere? If not, then strange things are >never observed. It occurs in deep space. One 'strange thing' that IS observed is that light speed is source dependent. Thus we see many variable star brightness curves that agree with the BaT. >>>> >>>> Well, ain't that longer that 5 feet? >>> >>>Yes, but what did it have to do with my question as to what you >>>considered to be 'distant'. >> >> 5 feet is NOT distant compared with say, the wavelength of 100 hz EM. > >Lets get back to light again, is 5 feet 'distant' with respect to 500 nm >EM radiation? [visible light, in case you are wondering]. So what? > >> >>> >>>If you say NO, I will ask why not. If you say YES, then we can go into >>>the lab and test your theory. >>> >>>So how far is 'distant'? >> >> Sorry, I don't have the slightest idea what you are talking about. > >If 5 feet is 'distant' where 500 nm light is concerned (and I think it >should be because it is millions of wavelenghts) then we can test your >statements in the lab with a 5 ft optical bench and some other equipment. You will need two separated clocks that can only be synched with light. HW. www.users.bigpond.com/hewn/index.htm Sometimes I feel like a complete failure. The most useful thing I have ever done is prove Einstein wrong. |