Speed of Light: A universal Constant?
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From: The Ghost In The Machine on 4 Apr 2005 23:00 In sci.physics, H@..(Henri Wilson) <H@> wrote on Mon, 04 Apr 2005 10:09:41 GMT <gh4251dpkork18r2kknvn2gu6lt979b8m3(a)4ax.com>: > On Sun, 03 Apr 2005 23:00:04 GMT, The Ghost In The Machine > <ewill(a)sirius.athghost7038suus.net> wrote: > >>In sci.physics, H@..(Henri Wilson) >><H@> >> wrote >>on Sun, 03 Apr 2005 08:45:18 GMT >><16bv4112a99gjs54gmro5c0hrsb9rtfak2(a)4ax.com>: >>> On Sun, 03 Apr 2005 01:00:07 GMT, The Ghost In The Machine >>> <ewill(a)sirius.athghost7038suus.net> wrote: >>> >>>>In sci.physics.relativity, H@..(Henri Wilson) >>>><H@> >>>> wrote >>>>on Sat, 02 Apr 2005 23:21:50 GMT >>>><f5au41p1m4h5pjacaresa5e6082hcuro8q(a)4ax.com>: >> >>[crunch] >> >>>>Optical fibre would suffer the same signal-speed anisotropy >>>>as electrical cabling. That is not a solution. >>>> >>>>Of course, it turns out signal-speed anisotropy is not >>>>really a problem, either. :-) OLWS lightspeed is isotropic >>>>to a few parts per billion, if my memory is correct >>>>regarding certain experiments thereon. (My memory also >>>>tells me that the experiments did not measure OLWS directly.) >>> >>> Well Ghost, I was trying to keep that a secret >>> >>> It is true because light speed is source dependent. >> >>And what experiments show this source dependency? >> >>Color me curious. > > Ghost, is not velocity always specified relative to something? Yes. The velocity of light is c relative to any observer. > > Is not the speed of light always 'c' wrt its source? And the observer. > > 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) :-) [.sigsnip] -- #191, ewill3(a)earthlink.net It's still legal to go .sigless.
From: The Ghost In The Machine on 4 Apr 2005 23:00 In sci.physics, H@..(Henri Wilson) <H@> wrote on Mon, 04 Apr 2005 21:31:29 GMT <u6c351du1rm845dlvhj309smegtid0gnm9(a)4ax.com>: > On Mon, 4 Apr 2005 12:09:32 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> wrote: > >>H@..(Henri Wilson) wrote in news:gh4251dpkork18r2kknvn2gu6lt979b8m3@ >>4ax.com: >> >>> Ghost, is not velocity always specified relative to something? >>> >>> Is not the speed of light always 'c' wrt its source? >>> >>> >> >>The velocity of light is always c with respect to the observer. > > Proof please! No proof available. At best, there are several experiments that show evidence for this statement, a number of indirect experiments that show evidence for related concepts, and a number of observations of astrophysical phenomena that show evidence for other related concepts given certain assumptions. There is reasonably good evidence that c' != c+v, if you like. That's arguably the best we can do. Uncle Al is working on evidence that general relativity doesn't quite work in the corner cases. I'll have to let him explain parity/affine gravity to you; I don't have the knowledge. (I'm not sure he has the patience. :-) ) This doesn't mean that we can replace it with c' = c+v. > >>If the observer is in the source's frame of reference (and there could >>always be an observer in that frame) then they will measure the velocity as >>c > > That is what the ballistic theory predicts, yes. > >> >>If the observer is in some other frame of reference, they will ALSO measure >>the velocity as c, regardless of the relative motion of the observers. > > Proof please. See above. > >> >>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? What causes a diffraction pattern for single electrons? > >> >>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? http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/gratim.html#c2 gives a good layman's description of the Harvard Tower experiment. [.sigsnip] -- #191, ewill3(a)earthlink.net It's still legal to go .sigless.
From: The Ghost In The Machine on 4 Apr 2005 23:00 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. > >> >>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. [.sigsnip] -- #191, ewill3(a)earthlink.net It's still legal to go .sigless.
From: Henri Wilson on 5 Apr 2005 01:41 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. Let's use a spinning wheel of radius 2/pi metres, rotating at 250 rps. Its circumference is 4m. It should not fly apart. 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)) 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. Best of luck Ghost. (Please check my figures). > >[.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 5 Apr 2005 01:49
On Tue, 05 Apr 2005 03:00:09 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 21:31:29 GMT ><u6c351du1rm845dlvhj309smegtid0gnm9(a)4ax.com>: >> On Mon, 4 Apr 2005 12:09:32 +0000 (UTC), bz <bz+sp(a)ch100-5.chem.lsu.edu> wrote: >> >>>H@..(Henri Wilson) wrote in news:gh4251dpkork18r2kknvn2gu6lt979b8m3@ >>>4ax.com: >>> >>>> Ghost, is not velocity always specified relative to something? >>>> >>>> Is not the speed of light always 'c' wrt its source? >>>> >>>> >>> >>>The velocity of light is always c with respect to the observer. >> >> Proof please! > >No proof available. At best, there are several experiments >that show evidence for this statement, a number of indirect >experiments that show evidence for related concepts, and >a number of observations of astrophysical phenomena that >show evidence for other related concepts given certain >assumptions. Yes, yes Ghost, we know all about those, Haha! > >There is reasonably good evidence that c' != c+v, if >you like. That's arguably the best we can do. There is no evidence to that effect. > >Uncle Al is working on evidence that general relativity >doesn't quite work in the corner cases. I'll have to let >him explain parity/affine gravity to you; I don't have >the knowledge. (I'm not sure he has the patience. :-) ) > >This doesn't mean that we can replace it with c' = c+v. I wouldn't even read anything Al the cretin wrote anyway. > >> >>>If the observer is in the source's frame of reference (and there could >>>always be an observer in that frame) then they will measure the velocity as >>>c >> >> That is what the ballistic theory predicts, yes. >> >>> >>>If the observer is in some other frame of reference, they will ALSO measure >>>the velocity as c, regardless of the relative motion of the observers. >> >> Proof please. > >See above. none. > >> >>> >>>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? > >What causes a diffraction pattern for single electrons? .....an equally good question...and one that will never be answered while physics remains tied to the Einsteiniana bogey train. > >> >>> >>>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? > >http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/gratim.html#c2 > >gives a good layman's description of the Harvard Tower experiment. Yes Ghost. The Pound-Rebka experiment showed that the energy of gamma particles increased by exactly that expected under normal gravitational acceleration of light. This is one area where GR agrees with the ballistic theory. ..but for the wrong reasons. > >[.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. |