Speed of Light: A universal Constant?
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From: Henri Wilson on 6 Apr 2005 01:07 On Tue, 05 Apr 2005 07:00:09 GMT, The Ghost In The Machine <ewill(a)sirius.athghost7038suus.net> wrote: >In sci.physics.relativity, H@..(Henri Wilson) ><H@> > wrote >on Tue, 05 Apr 2005 05:41:38 GMT ><2n74519tmld8ti3em4sijpbluhbbiuktcv(a)4ax.com>: >> On Tue, 05 Apr 2005 03:00:10 GMT, The Ghost In The Machine >> <ewill(a)sirius.athghost7038suus.net> wrote: >> >>>In sci.physics, H@..(Henri Wilson) >>><H@> >>> wrote >>>on Mon, 04 Apr 2005 22:14:46 GMT >>><4pe3515eoun2ldfbplkjrutemt7aca6bld(a)4ax.com>: >>>> On Sun, 03 Apr 2005 23:00:05 GMT, The Ghost In The Machine >>>> <ewill(a)sirius.athghost7038suus.net> wrote: >>>> >>>>>In sci.physics, bz >>>>><bz+sp(a)ch100-5.chem.lsu.edu> >>>>> wrote >>>> >>>> >>>>>> >>>>>> All I need to establish is that the travel time of the photon does not >>>>>> change as the speed of the source is changed. >>>>>> >>>>>> I just want to establish that the doppler effect is NOT due to a change in >>>>>> the velocity of the photon. >>>>>> >>>>> >>>>>Hmmm...well, here's a thought. >>>>> >>>>>I'll assume that we have a set of mirrors mounted on the >>>>>edge of a rapidly rotating disc, and that the stationary >>>>>light source is firing *away* from the destination into the >>>>>disc, and that the destination will pick up the reflected >>>>>signal. What would be the predicted frequency of the >>>>>received lightsignal, assuming a certain edge velocity v >>>>>towards the destination and a laser source of 500 nm >>>>>(pea-green), or 600 THz or 1.67 fs? >>>>> >>>>>Emissive: From the mirror's perspective, the light hits at >>>>>c + v and reflects at c + v. Since the mirror is moving >>>>>towards the light the incident and reflected frequency will >>>>>be 600 THz * (c+v) / c. Since the receiver is also moving >>>>>towards the mirror the receiver will see a frequency of >>>>>600 THz * (c+v)^2 / c^2. Delta frequency would be >>>>>600 THz * (2*v/c+v^2/c^2). >>>> >>>> Bull. >>>> >>>>> >>>>>Emissive Alternate 1: The receiver will instead see a >>>>>frequency of 600 THz * (c+2*v)/c. Delta is therefore >>>>>600 THz * 2*v/c. >>>> >>>> Correct. >>> >>>Either way, you're screwed. >> >> Never! >> >>> >>>> >>>>> >>>>>SR: From the mirror's perspective the second light wave >>>>>(we assume the first is at (0,0)) will transform as follows, >>>>>assuming t = 1.67 fs: >>>>> >>>>>(0, t) => (-g*v*t, g*t) >>>> >>>> there is no foundation for these transforms. they don't >>>> happen...so why bother Ghost? >>> >>>And what foundation precisely are you seeking? >>> >>>All *I* have is theory. I lack precision to even properly >>>measure lightspeed. (I suppose I could observe Jupiter's moons, >>>and try to work out its orbital parameters relative to ours >>>or something. That's arguably the best I can do and would >>>probably take several months -- and would lack sufficient >>>precision to show c constant for all observers.) >>> >>>> >>>>> >>>>>or an observed delta time of g*t-g*v*t/c = g*t*(1 - v/c), >>>>>where g = 1/sqrt(1-v^2/c^2). >>>>> >>>>>The mirror faithfully reflects this pulse and since the >>>>>receiver is also moving in the exact same fashion to the >>>>>mirror as the mirror was to the source, the receiver >>>>>will see a time interval of g^2*(1-v/c)^2, and >>>>>therefore a frequency shift of (1 - v^2/c^2) / (1-v/c)^2. >>>>>Delta frequency is therefore >>>>>(1 - v^2/c^2 - 1 + 2*v/c - v^2/c^2) / (1-v/c)^2 >>>>>= (2*v/c - 2*v^2/c^2) / (1-v/c)^2 = (2*v/c)/(1-v/c). >>>>> >>>>>If one assumes a carefully knurled disc where the "knurls" >>>>>are reflective, and it is of size 5" = 12.7 cm in diameter >>>>>with a rate of 10,000 RPM (perfectly possible in light of >>>>>modern disk drives), one gets an edge velocity of 10000 >>>>>revs/minute * 1/60 min/sec * Pi*0.127 m/rev = 66.5 m/s. >>>>>66.5 m/s = 2.2 * 10^-7 c. >>>>> >>>>>Emissive Delta: 265988207.48 >>>>>SR Delta: 265988236.96 >>>>>Delta of Deltas: -29.48 >>>>> >>>>>Alt 1 Delta: 265988178.00 >>>>>Delta of Deltas: -58.96 >>>>> >>>>>This looks doable but the faster the mirrors, the better, >>>>>and one would have to establish the precise velocity >>>>>thereof. Of course one other possibility is to do the >>>>>experiment both ways, with the knurls splitting the beam. >>>>>One subbeam would go towards the detector and the other to >>>>>either another detector or to a mirror arrangement which >>>>>would eventually interfere with the first beam. There's >>>>>the issue of vibration, as well. >>>> >>>> >>>> I have investigated the spinning wheel/mirror idea before. >>>> >>>> Even at around 50000 rpm and 30kms separation, the difference >>>> between c and c+v is almost certainly too small to be measured. >>> >>>Define "too small to be measured". I'll admit I don't see >>>major problems, though I'm not sure how badly vibration >>>will affect the spinning disc, or how to properly >>>heterodyne two lightbeams. >>> >>>The deltas, however, are very clear. >> >> work it out. > >I did. See above. > >> >> Let's use a spinning wheel of radius 2/pi metres, rotating >> at 250 rps. Its circumference is 4m. It should not fly apart. > >I wouldn't know offhand. It presumably depends on the >strength of the materials. > >> >> Using a powerful laser beam, it might just be possible >> to detect each individual pulse of light reflected from >> the mirror at 30000 metres distance if the experiment is >> carried out on the tops of high mountains. If the detector >> has a width of say 10 cms, the pulse intensity as it flashes >> past will be only about 1/(2000000) that of the laser . >> >> So the maximum mirror speed is 1000 m/s, or 3.3x10^-6c. The >> reflected light will return to the source at c plus double >> this speed. (c(1+(6.7x10^-6)) > >Depends on which way the wheel is rotating. > >> >> Light takes 10^-4 secs to travel 30kms. >> >> So the return travel time difference between pulses moving at c and c+v is >> about 6.7 x 10^-10 secs. > >670 picoseconds. I don't see an intrinsic difficulty in detecting >such -- though one won't detect much of such as SR predicts >exactly 0. > >A heterodyning solution involves a smaller, slower wheel, as you >may already have noticed. It's more sensitive. There are problems though. I'm not exactly sure what you mean but if the beam is not perfectly uniform (in time) the reflected spot will magnify any irregularities. It will be whizzing past at 5*10^9 m/sec in my configuration. > >> >> Best of luck Ghost. >> >> (Please check my figures). > >They look OK, given your theory. I don't expect it to work, though. If it were done on the moon it probably would. > >[.sigsnip] 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 6 Apr 2005 01:12 On Tue, 05 Apr 2005 12:51:28 -0700, David Cross <spamdenied(a)nospam.net> wrote: >On Mon, 04 Apr 2005 21:31:29 GMT, H@..(Henri Wilson) wrote: > >>>The velocity of light is always c with respect to the observer. >> >>Proof please! > >Several different measurements done different ways haven't convinced you of >this? There is doubt of empirical observation due, perhaps, to inherent error >in the measurements, and then there is just plain die-hard refusal to face >facts. > >>>The wavelength, on the other hand, will not be a constant if the observer >>>is in motion with respect to the source. >> >>what causes the phenomenon we call 'wavelength' in single photons? > >You can get it from the de Broglie relationship and the fact that a photon's >momentum and energy are interrelated. > >>>As far as I know, over 100 years of observations confirm this. >>>Do you have any data that invalidates this? >> >>Doppler shift is caused by varying relative light speed >> >>Do you know of anyone who has observed a doppler shift in a gamma particle? > >Doppler shifting is how the Mossbauer Effect works. That's an oversimplification...and a bit of circular logic. The Mossbauer Effect works on energy change. > >--- >David Cross >dcross1 AT shaw DOT ca 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 6 Apr 2005 01:19 On 5 Apr 2005 12:57:04 -0700, "PD" <pdraper(a)yahoo.com> wrote: > >Jim Greenfield wrote: >> The Ghost In The Machine <ewill(a)sirius.athghost7038suus.net> wrote in >message news:<l9a9i2-f6i.ln1(a)sirius.athghost7038suus.net>... >> > In sci.physics, H@..(Henri Wilson) >> > <H@> >> >> Primary assumption that has mired physics / astronomy for decades >> being that >> Doppler is falsely attributed to a magical wavelength alteration, >thus >> skewing >> many measurements as to distance, velocity and composition (spectra) > >And this shows you know nothing about how light's wavelength is >measured. One approach that's been around for years is the diffraction >grating. With a diffraction grating, light of a particular wavelength >is scattered and shows constructive interference at an angle that is a >function of the ratio of the light's wavelength and the spacing of the >etching in the grating. Nothing else -- no c's, no frequencies, no >other buried physics -- just the ratio of the light's wavelength to the >spacing of the etching the grating, a ratio of two distances. This is a question that I have raised recently. I reckon the diffraction angle is somehow dependent on the rate at which fronts of equal phase pass the lines. So light speed DOES come into it. > >If what you say were true, that the wavelength stayed the same but the >speed and frequency changed, then a blue line shifted to green by the >Doppler effect would emerge from the grating at exactly the same angle >as the unshifted blue line. Why? Because, if what you say were true, >the wavelength would be the same and the spacing of the etching would >be the same, so the ratio of those two distances would be the same. > >This is demonstrably NOT the case. In spectrometers, we have >verification that the angle for a blue line shifted to green (and seen >to be green by taking a color film plate) falls exactly where an >unshifted *green* line should fall, not where the unshifted blue line >should fall. Thus, we have measurement of both frequency and >wavelength, showing that both are shifted. The product of the >wavelength and frequency, even for the shifted lines, is (miraculously) >c. > >There are no holes, no hidden assumptions, Jim. What you propose is >flat-out ruled out experimentally. It does not hold water. No it isn't. The theory is wrong. Everyone knows light cannot be treated like a pure wave in a medium. It is also corpuscular. If you throw away all your Einsteiniana, you might start thinking constructively. > >PD > >[snip] 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 6 Apr 2005 01:29 On 5 Apr 2005 00:20:46 -0700, "Sue..." <suzysewnshow(a)yahoo.com.au> wrote: >Henri: ><< So when light leaves a remote star somewhere out in space, that >light is >automatically moving at c wrt every other body in the universe, is it >Ghost? >> > >When potential emitters perform light production ceremonies, it is not >clear >at all that anything will actually be radiated. (sort of like hiring an >amateur >rain-maker) ;-) > >For example, if the coupling structure has a effective E plane aperture >of >zero ( a Faraday shielded loop ) then the only component produced will >be magnetic. Without the help of some neighboring matter to increase >the E plane aperture, the field will diminish by the cube of the >distance. > >This is hardly the robust performance we expect from what we generally >term as "light". > >The point is: you can't say how fast *light* is moving wrt the emitting >structure, if you can't even discern that it is light. > >When you consider, the *position* of adjacent structures which might >magnify the E plane aperture, you have added an uncertainty to the >position. > >If you want to say the emitting structure is a single atom, then you >must apply HUP to your speed determinations. > >The bottom line Henri, is that light can't go very far, or perhaps >even exist without considerable interaction with nearby matter. Are you claiming that a pulse of light doesn't take a certain time to traverse a length of completely empty space? > >Do you think the manufacturers of dielectric antenna would be >in business if light behaved the according to your model ? There is a vast difference between a single 'photon' and a generated EM radio wave (Maybe many photons in some kind of phase relationship) > > >Sue... 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 6 Apr 2005 01:33
On Tue, 05 Apr 2005 08:00:03 GMT, The Ghost In The Machine <ewill(a)sirius.athghost7038suus.net> wrote: >In sci.physics.relativity, H@..(Henri Wilson) ><H@> > wrote >on Tue, 05 Apr 2005 05:52:39 GMT ><9o9451lcsp6cckqqqtve3iolli1j05kele(a)4ax.com>: >> On Tue, 05 Apr 2005 03:00:08 GMT, The Ghost In The Machine >> <ewill(a)sirius.athghost7038suus.net> wrote: >> >> So when light leaves a remote star somewhere out >> in space, that light is automatically moving at c >> wrt every other body in the universe, is it Ghost? >> >> You really make the most outrageous claims, Ghost. > >If you think that's outrageous, try this one. > >A light quanta can be everywhere within the subarea of >the 4-dimensional Universe defined by the equation > >(x - x_0)^2 + (y - y_0)^2 + (z - z_0)^2 - c^2 * (t - t_0)^2 = 0 > >which can be construed as an expanding sphere, if one >conventionally takes t as time. If one observes this >wavefront from another vantage point (e.g., a moving >spacecraft) it will *still be an expanding sphere*. >It won't be squished, distorted, or otherwise mangled. >It might move its center, but that's about it. > >In any event, SR is quite clear: all observers will see that >pulse of light traveling at the same velocity. It won't >be the same frequency, however. That's just aether theory in which the one absolute frame is replaced by an arbitrary one. It is completely unproven. > >> >>> >>>> >>>> Can you put two and two together Ghost? >>> >>>I already did. >>> >>>Depending on the units of "two", one gets rather odd results, >>>but they can be expressed as >>> >>>2 * two / (1 + (two)^2/c^2) >> >> You are obsessed.! > >No, just being slightly silly. Don't you recognize the SR >velocity addition formula? :-) Of course I did. > >[rest snipped] Ghost, why did you snip my question? Was it too hard to answer. Here it is again: Do you claim that light emitted from a remote star is initially traveling at c relative to every object in the universe? Does that require an infinite number of discreet speeds? 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. |