Speed of Light: A universal Constant?
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From: Sue... on 9 Apr 2005 16:00 bz <<No single photons, a lot of married ones. 2.517E+26 per second, if my transmitter has 5 watts output. >> s Shhhhhh... ya don't want the PET scanner folks to find out you are marrying gammas and anhililating antimatter at that rate with an amateur radio transmitter. They will want you to squeeze it inside a cell phone with downloadable version of "play doctor" ;-) Sue..
From: bz on 9 Apr 2005 15:55 "N:dlzc D:aol T:com \(dlzc\)" <N: dlzc1 D:cox T:net(a)nospam.com> wrote in news:KRV5e.6445$EX4.4126(a)fed1read01: > Dear bz: > > "bz" <bz+sp(a)ch100-5.chem.lsu.edu> wrote in message > news:Xns9633824B59BF5WQAHBGMXSZHVspammote(a)130.39.198.139... >> "N:dlzc D:aol T:com \(dlzc\)" <N: dlzc1 D:cox T:net(a)nospam.com> >> wrote in >> news:p2S5e.6044$EX4.5168(a)fed1read01: > ... >>>> And that is for plane polarized. For circular >>>> polarized, you would see one twist. >>> >>> You see a *signal* twist. You see *nothing* >>> for a single photon. >> >> The OAM Orbital Angular Momentum people >> seem to think that photons have finite length >> and they think all photons have OAM. I am >> not sure about all of their ideas, yet. >> >>>> A coherent STREAM of photons would look >>>> as you describe 'signal'. >>> >>> Including exhibiting a variable E and/or >>> B, and providing the characteristic >>> self-interference pattern. >> >> Single photons exhibit interference in >> dual slit experiments. > > Single photons arrive at locations indistinguishable from > "random". Only when you have a population, is a pattern > revealed. And this all says as much about the geometry through > which the photon stream passed, as it does the photon stream. > http://www.teachspin.com/products/two_slit/experiments.html A dual beam experiment, working with single photon events, shows that single photons carry polarization information. http://web.phys.ksu.edu/vqmorig/tutorials/online/wave_part/ >>>>> You will note that the photons pass you also at c. >>>> >>>> yes. >>>> >>>>> So the photon has no length (from left to right). >>>> >>>> length of each photon is c/f >>> >>> Experimentally determined to be zero length. >>> There is no experiment than can get >>> wavelength information from a single photon... >>> only its energy. >> >> what about scattering of single photons from >> a diffraction grating? > > Individual photons express "random". Populations express > "pattern". See previous references. Single photons are NOT random. > >>>>> Only the >>>>> number of photons varies along the path >>>>> (think intensity), not some geometry of a >>>>> single photon. >>>> >>>> not sure exactly what you mean by this. I >>>> understand intensity. If the source is >>>> incoherent, size (wavelenght), orientation, >>>> and position will vary as well as direction >>>> of travel. >>> >>> Imagine that the peak E of a coherent >>> laser beam is populted with a lot of >>> "photons per transverse slice", and a >>> quarter wavelength away, very few >>> photons are located. >> >> So, you have a pulsed laser beam? > > Such exist. Down to femtosecond pulses, and terawatts. Yes. I have only worked with 500 W cw CO2 lasers and with lower average power YAG, CO2, diode and dye lasers. > ... >>>>> You can run a long wavelength signal through >>>>> a spinning drum with two slits, and the signal >>>>> doesn't get "spun around" as if the photons >>>>> were caught in the slits... and diverted from >>>>> their course. >>>> >>>> Can you? >>> >>> Yes. Several methods of determining c used such. Some >>> included >>> rotating mirrors, which provides even more difficulties for >>> your >>> imagined photon structure, since each photon would now be >>> tortured into a much longer wavelength and mixed momentum. If >>> photons were such long creatures as you imagine, these >>> constructs >>> would not work. But they did, and did it without affecting >>> the >>> wavelength. >> >> an 850 nm signal has a period of 2.8e-3 pico seconds. > > And on a rotating mirror, over tens of kilometers between > source/detector and mirror, the effect on a finite length photon > would be nothing? I don't know. I suspect that some photons might be lost. Some might show a doppler shift. Do you know of any experiment that looked for photons OFF the expected path? > > Consider reflection of your finite length photon. At one point > during reflection, the E and B field exactly cancel each other > out. A zero length particle, a quantum of an established E and B > field, doesn't have this problem. A zero length particle has other problems. Interaction with slits, for one thing. > >>>> Have you tried it? I don't know of anyone that >>>> has spun a slit anywhere near the frequency >>>> of the EM radiation. >>> >>> 60Hz can be EM radiation. >> >> No one has ever detected a single photon at >> 60 Hz. The wavelength is 6,000 km. The energy >> is 4e-32 Joules. Much too weak to be detected >> as a single photon except very close to >> absolute zero because of thermal noise. > > So you could not reflect a 60 Hz signal from a spinning mirror, > right? Not unless you have ONE huge mirror, that is for sure. :) > Don't get distracted about the photon issue... > concentrate on what it would mean for a photon to have a physical > length that is some function of its "wavelength". I am. But when you cite 60 Hz EM radiation we must look at the implications. > >>> 1m corresponds to a wavelength. >> >> 1 meter has a frequency of 300 MHz >> and an energy 2e-25 Joules. I doubt >> that one meter single photons have >> been detected. > > So I approach this 1m wave source with a gamma of 1000. > Will I > be able to detect individual photons then? Sie Sie. Almost certainly. > Don't distract > yourself with our current detection abilities. I won't, if you don't distract by citing long wavelength photons. > >>> Don't be silly. >> >> I try not to be. > > Well, then try to be. I just be me. >>>> When you run a polarized beam through a >>>> layer of mylar film that is under stress, the >>>> plane of polarization gets rotated. When >>>> the source is white light and the polarizers >>>> are crossed, you see bright, colorful areas >>>> showing the stress in the plastic. >>> >>> Which says something about: >>> - the signal passed through the mylar, and >>> - the variable speed of light in mylar >>> *nothing* about a single photon is revealed. >>> Because you can do the same test with >>> gamma or even x-rays and polarization is >>> unaffected. >> >> I fail to follow your logic. >> >> Why would we expect Gamma or x-rays to >> be effected by polarizers that work for visible >> light? Why would we expect mylar film to >> effect either? > > If the "mechanism" of mylar affects light based on a finite > photon length, why should it not have the same effect on shorter > wavelengths? Because mylar[and everything else] has different effects on different frequencies of EM radiation. > Since transmission is a complex phenomenon > involving resonance, it makes sense that on *that* basis, > re-emission of an *absorbed* photon will affect the detected > polarization. It says nothing about a finite length photon. Nor does it exclude such. > >> I suspect that single photons from a white >> light source, run through the polarizer mylar >> polarizer would show that certain energy >> photons were selectively absorbed and >> others passed just as with the bulk stream >> of white light. >> >> When I go in my ham shack and turn my >> transmitter on 29.96 MHz, I generate a LOT >> of 10 meter photons. By your theory, some >> of these 2e-26 Joule photons start popping >> out of my 5 meter long, half wave antenna, >> at the very beginning of the 33 ns period of >> the wave? Somehow I don't think so. > > Is your antenna at something other than 0K? If so, you can > believe that you are radiating all sorts of photons from it. > Consider what a photomultiplier tube can do with single photons > from distant stars. My antenna is certainly emitting at many frequencies since it is above absolute zero. However there is no significant coherent radiation until I key my transmitter. Just when, in the first cycle, does the antenna finally emit is first burst of 29.96 MHz photons. How does it know to emit 29.96 MHz photons, at that moment, rather than 29.959 MHz? -- bz please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. bz+sp(a)ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap
From: Henri Wilson on 9 Apr 2005 18:48 On Sat, 9 Apr 2005 08:53:31 +0100, "George Dishman" <george(a)briar.demon.co.uk> wrote: > >"Henri Wilson" <H@..> wrote in message >news:nl0a51tnupghqese7t86l3g4p18o6338sg(a)4ax.com... >> On Wed, 6 Apr 2005 23:36:36 +0100, "George Dishman" >> <george(a)briar.demon.co.uk> >> wrote: >>>"Henri Wilson" <H@..> wrote in message >>>news:65g851dn7asmetb67jjv5cnue56cbsjlai(a)4ax.com... > ><much discussion trimmed, line lengths reduced> > >>>> Put it another way, when the >>>> apparatus is rotating, the sections of the two >>>> beams that arrive simultaneously at any point >>>> did not leave the source at the same instant. >>> >>>I agree, that is what my other simulation >>>will try to illustrate. >> >> I still cannot see why fringe pattern should >> change at all while the apparatus is rotating at >> constant speed. > >OK Henri, I got it working. I have used a >circular path appropriate for the iFOG >technology I mention on the site. The are >some important engineering aspects in real >devices but the principle of operation >remains the same and is also applicable to >the original experiment with mirrors and >straight paths. > >http://www.briar.demon.co.uk/Henri/iFOG.html Yes that works nicely. It shows the standard explanation of ring gyros. It appears on the surface to be perfectly sound. I accept that rotation CAN be detected absolutely but I don't agree with that explanation because it ignores the fact that light is actually being internally reflected an infinite number of times by and infinitesimal amount. I only want to analyse the four mirror system. Your demo would have to consider a few other factors then. > >I haven't found out how to stop the slider >being reset when you reset the simulation so >after each run, press reset before adjusting >the table speed. Remove the default slider setting. Declare an initial value that operates only on the program load. After that, the setting should retain its current value. > >You should think of the fast-moving dots as >being a single wavefront that has been split >to go in both directions. I might change >them to short line segments later. > >The bottom line is that the speed of the >light cannot be c+v in the lab frame or >there would be no output, and it exactly >matches the result of the experiment if it >is precisely c regardless of the speed of >the source. No, I will not give an opinion until I see the four mirror analysis. > >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 9 Apr 2005 19:01 On Sat, 09 Apr 2005 05:00:03 GMT, The Ghost In The Machine <ewill(a)sirius.athghost7038suus.net> wrote: >In sci.physics, H@..(Henri Wilson) ><H@> > wrote >on Fri, 08 Apr 2005 21:57:34 GMT ><toud51910nit3uai1tc9i9al49l36778jn(a)4ax.com>: >> On Fri, 08 Apr 2005 04:00:03 GMT, The Ghost In The Machine >> <ewill(a)sirius.athghost7038suus.net> wrote: >> >>>In sci.physics, H@..(Henri Wilson) >>><H@> >>> wrote >> >>>>>> Empirical fact of life, Jim. >>>>>> >>>>> >>>>>Confirmable, as well. The SR and the BaT predict different results >>>>>for such things as spectroscopic binaries, even if one can't >>>>>measure the speed directly. >>>> >>>> You are very confused now Ghost. Getting desperate I would say. >>> >>>Am I? >>> >>>Here's a hint for you. Assume two stars traveling around a common >>>center at 30 km/s = 10^-4 c, although we can't tell the speed directly. >>>What would be the wavelengths observed as these stars orbit each other, >>>assuming a spectral line initially at 500 nm [*] and an approximate >>>distance of 10 lightyears? >>> >>>BaT: >>> >>>The star is spewing out particles at lightspeed, relative to itself. >>>These particles are of course 500 nm apart. However, since the >>>star is moving toward us, the particles in realspace will be a >>>tad longer apart -- namely, 500.05 nm apart. The other star >>>moving away from us will generate light of wavelength 499.95 nm, >>>as measured by us. The delta is 120.0000012 GHz between the two signals. >> >> Question, Ghost: >> What is this 'realspace'? >> Is it another name for the aether? > >Realspace is space as Earth perceives it. Perhaps I should have used >a slightly different term. > >> >> You are definitely very confused Ghost. >> The wavelength is the same no matter how you look at it. > >It cannot be the same if the velocity changes. > >> >> Proof: let the star fire a identical rods between each particle....... >> >> S_._._._._._._._._._._._. >> >> You can see that the distance between particles is constant. > >Hmm...an interesting issue, that. Not sure quite how to attack it. You cannot attack plain fact. > >But OK, an alternate explanation is that Earth will see >*no* shift *at all* in the wavelength, but will see an >energy difference. The receding star has lightvelocity >.9999 c, which will yield an energy .99980001 of nominal >(recall that E = 1/2 m v^2 in Newtonian mechanics). >The advancing star has lightvelocity 1.0001 c, with an >energy 1.00020001 of nominal. Since detectors are not >designed with E versus lambda issues in mind this will >screw up a lot of things if not done strictly according >to Henri. > >For example, I could see a rather simple detector >monitoring whether current flows from a sensitized surface >to an anode, depending on a voltage drop between the >surface and the anode, and whether light of a certain >frequency is falling thereon. This detector keys on >energy, not on wavelength, according to current QM >theory (or my understanding thereof), and therefore BaT >predicts that it will be affected. However, a classical >interferometer which keys on *wavelength* (e.g., MMX) >will see no change. In the MMX, all components are mutually at rest. There is constant wavelength throughout. > >> >>> >>>The signals will be timeshifted relative to each other as the signal >>>from the star approaching us will reach us slightly more quickly. >>>The time delta here will be approximately 2 * 10^-4 * 10 = 31557 >>>seconds, or 8 hours, 45 minutes, 57 seconds. Depending on the star's >>>orbital period this should be easily measurable. >>> >>>SR [+]: >>> >>>The gamma is (1 - 5.0000000375 * 10^-9). If we assume the star >>>is moving directly towards us then t_O = (t_A - v * x_A / c^2) * g. >>>Also t_O' = (t_A' - v * x_A / c^2) * g. The difference is >>>(t_A' - t_A) * g. Since x_O = (x_A - v * t_A) * g and >>>x_O' = (x_A - v * t_A') * g, there is a corrective factor, >>>even though x_A = 0, and the final difference will be >>> >>>T_1 = g * ( (t_A' - t_A) - (v/c) * (t_A' - t_A)) >>> >>>for star #1, and >>> >>>T_2 = g * ( (t_A' - t_A) + (v/c) * (t_A' - t_A)) >>> >>>for star #2. Since v = 10^-4 c and t_A = 1.667 * 10^-15 s, >>>we get T_1 = 1.666500008332 * 10^-15 or f_1 = 600060003000300, >>>and T_2 = 1.6668333416675 * 10^-15 or f_2 = 599940002999700. >>>Frequency difference: 120.0000006 GHz. >>> >>>The signals will approach Earth and reach here at exactly the same time. >> >> Why bother with all that circular maths, Ghost. >> It was all derived from the postulate that the light from both stars >> WILL take the same time to reach the observer. Naturally that will >> be your conclusion. >> >> ...but why don't you simply state the (unproven) postulate. > >I already have. All light travels at exactly the same speed, >regardless of observer [*]. This postulate can never be proven. >It is not only an unproven postulate, but an *unprovable* one. It can now be proven wrong with my 'moon relay' experiment. >(There's a difference.) The best we can do is either adopt the >postulate, or accept that we can at best prove it within experimental >error (e.g., an experiment in the late 1970's or early 1980's proved >to be too much for the old KR-86 definition of the meter). > >However, the postulate c' = c+v has been proven -- to be false. >Several experiments involving decaying muons and or pi mesons >have shown strong evidence that the lightspeed from a high-speed >particle is still c relative to the lab. Sufficiently precise >radar waves from Venus (which moves at about 35 km/s, or >5 km/s relative to us) should also establish lightspeed issues. There is an anomalous delay in radar to/from venus adn the moon. This is fully explained by the ballistic theory. Earth is heaver than both and so the average light speed during the trip is less than c. I have calculated the delay for the moon to be about 1.4E-7 secs. > >However, none of this is proof that c'=c -- just very good evidence. > >> >>> >>>I won't go into details regarding precession and period changing, >>>as I lack the mathematical expertise therein. However, it's >>>clear there *is* a difference, although not a discernable one in >>>this case (too much imprecision in the distance and velocity >>>measurements). >> >> Ghost, you have made an error in your original assumptions, therefore your >> whole theory is wrong. > >Well, take your pick then. Either the delta-wavelength is 0, or >it's as I've computed. Either way, it differs from SR's predicted >results. In that case it could be partly correct then. > >> >>> >>>Mercury's orbit is probably a better example. >> >> Yes, it is s long way from us, close to the sun, very hot and dry and in a >> fairly elliptical orbit. >> >> There are many possible explanations for its 'anomalous' precession. > >OK. Name one. Magnetic field interaction. (sun) The speed of gravity. 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 9 Apr 2005 19:08
On 9 Apr 2005 05:27:48 -0700, "PD" <pdraper(a)yahoo.com> wrote: > >Henri Wilson wrote: >> On Fri, 08 Apr 2005 04:00:03 GMT, The Ghost In The Machine >> <ewill(a)sirius.athghost7038suus.net> wrote: >> >> >In sci.physics, H@..(Henri Wilson) >> ><H@> >> > wrote >> >> >>>> Empirical fact of life, Jim. >> >>>> >> >>> >> >>>Confirmable, as well. The SR and the BaT predict different >results >> >>>for such things as spectroscopic binaries, even if one can't >> >>>measure the speed directly. >> >> >> >> You are very confused now Ghost. Getting desperate I would say. >> > >> >Am I? >> > >> >Here's a hint for you. Assume two stars traveling around a common >> >center at 30 km/s = 10^-4 c, although we can't tell the speed >directly. >> >What would be the wavelengths observed as these stars orbit each >other, >> >assuming a spectral line initially at 500 nm [*] and an approximate >> >distance of 10 lightyears? >> > >> >BaT: >> > >> >The star is spewing out particles at lightspeed, relative to itself. >> >These particles are of course 500 nm apart. However, since the >> >star is moving toward us, the particles in realspace will be a >> >tad longer apart -- namely, 500.05 nm apart. The other star >> >moving away from us will generate light of wavelength 499.95 nm, >> >as measured by us. The delta is 120.0000012 GHz between the two >signals. >> >> Question, Ghost: >> What is this 'realspace'? >> Is it another name for the aether? >> >> You are definitely very confused Ghost. >> The wavelength is the same no matter how you look at it. >> >> Proof: let the star fire a identical rods between each >particle....... >> >> S_._._._._._._._._._._._. >> >> You can see that the distance between particles is constant. >> > >[snip] > >This is precisely the problem. You imagine that a wavelength is emitted >from the source, fully formed, its length predestined. This is not the >case. Look at it this way: the source emits "blips" every so often. The >blips represent wavefronts (or whatever) that travel at a fixed speed >*relative to the observer* away from the source. But if the source is >moving away from the direction of transmission, the distance between >the blips/fronts (or whatever) will be larger than if the source were >stationary relative to the observer. That's plain wrong. You are confusing frequency with wavelength. Like I said, the source can hypothetically emit fixed rods between each blip. That permanently fixes the wavelength. >Likewise, if the source is moving >along the direction of transmission, the distance between the >blips/fronts (or whatever) will be smaller. Rubbish. The rate at which the blips reach the observer is what changes, not the distance between blips. > >PD 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. |