Speed of Light: A universal Constant?
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From: "N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox on 8 Apr 2005 23:36 Dear bz: "bz" <bz+sp(a)ch100-5.chem.lsu.edu> wrote in message news:Xns963252076623CWQAHBGMXSZHVspammote(a)130.39.198.139... > RP <no_mail_no_spam(a)yahoo.com> wrote in > news:s-udnaukW7_fksvfRVn- > ug(a)centurytel.net: .... > since the photons 'look like a point when seen > "end on"', but like waves when seen from the side. This is not correct. Imagine a signal passing left to right in front of you, in your God-like vision. You will note that the maximum E value passes you at c, and that it repeats itself each 1/f seconds. You will note that the photons pass you also at c. So the photon has no length (from left to right). Only the number of photons varies along the path (think intensity), not some geometry of a single photon. 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. David A. Smith
From: The Ghost In The Machine on 9 Apr 2005 01:00 In sci.physics, Jim Greenfield <jgreen(a)seol.net.au> wrote on 8 Apr 2005 15:58:50 -0700 <e7b5cc5d.0504081458.ba543f(a)posting.google.com>: > The Ghost In The Machine <ewill(a)sirius.athghost7038suus.net> wrote in message news:<evahi2-hq5.ln1(a)sirius.athghost7038suus.net>... >> In sci.physics, H@..(Henri Wilson) >> <H@> >> wrote >> on Fri, 08 Apr 2005 02:15:33 GMT >> <u9qb515cv860phceb8f9qjj5c313ju2ll2(a)4ax.com>: >> > On Thu, 07 Apr 2005 17:00:04 GMT, The Ghost In The Machine >> > <ewill(a)sirius.athghost7038suus.net> wrote: >> > >> >>In sci.physics, Sam Wormley >> >><swormley1(a)mchsi.com> >> >> wrote >> >>on Thu, 07 Apr 2005 12:41:29 GMT >> >><ZT95e.11438$g65.373(a)attbi_s52>: >> >>> Jim Greenfield wrote: >> >>> >> >>>> >> >>>> Absolutely I agree that speed=frequency x wavelength; what I >> >>>> absolutely disagree, is that the "speed" is always the same. >> >>>> >> >>> >> >>> 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. > > Not im my BaT! The particles (photons) will have the same separation, > but will arrive slightly sooner than simultaneously emitted photons > from the regressing star, and will appear to be bluer (higher > frequency). If they have the same seperation their color [*] will not change, although their energy will (they're moving faster). I agree that under BaT they'll arrive sooner. > As both stars emit a wide range of frequencies, and > differring "amounts" at each wavelength, the whole of the spectrums > would need to be analysed to see which star's light was more energetic > due to the motion of the source (KE of all the light). I am not > convinced that some of the redshifting might cause some photons to > become undetectable, so the results might still be questionable > (dammit) Stars consist of gas. This gas notches out certain frequencies, allowing for analysis of a star's composition. For example, http://www.webelements.com/webelements/elements/text/Fe/econ.html shows the spectrum for iron. http://www.webelements.com/webelements/elements/text/Na/key.html shows the pattern for sodium, which is rather simpler. > > Jim G > c'=c+v [*] wavelength, actually, though one might quibble here. Presumably, the eyes respond to packet energy somewhat a la the Compton Effect; a photon wiggles a molecule that eventually leads to a nerve impulse. However, a diffraction grating, which keys purely on wavelength, will not care, though the spread from a prism might. -- #191, ewill3(a)earthlink.net It's still legal to go .sigless.
From: bz on 9 Apr 2005 02:31 "N:dlzc D:aol T:com \(dlzc\)" <N: dlzc1 D:cox T:net(a)nospam.com> wrote in news:O4I5e.6012$EX4.3061(a)fed1read01: > Dear bz: > > "bz" <bz+sp(a)ch100-5.chem.lsu.edu> wrote in message > news:Xns963252076623CWQAHBGMXSZHVspammote(a)130.39.198.139... >> RP <no_mail_no_spam(a)yahoo.com> wrote in >> news:s-udnaukW7_fksvfRVn- >> ug(a)centurytel.net: > ... >> since the photons 'look like a point when seen >> "end on"', but like waves when seen from the side. > > This is not correct. Imagine a signal passing left to right in > front of you, in your God-like vision. You will note that the > maximum E value passes you at c, and that it repeats itself each > 1/f seconds. No. A photon is c/f long so the E max passes me only once in each polarity per photon. And that is for plane polarized. For circular polarized, you would see one twist. A coherent STREAM of photons would look as you describe 'signal'. > 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 > 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. > > 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? Have you tried it? I don't know of anyone that has spun a slit anywhere near the frequency of the EM radiation. 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. -- 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: Sue... on 9 Apr 2005 03:18 IMHO a charge in the emitter jiggles. That makes lots of other charges in the universe jiggle, Somebody names one of those many charges "detector" and watches it jiggle. All the rest is imaginary and probably half of the above too. ;-) Sue...
From: George Dishman on 9 Apr 2005 03:53
"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 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. 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. George |