Wang / Sagnac Devices
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From: Dono. on 22 Oct 2009 12:21 On Oct 22, 8:15 am, tominlag...(a)yahoo.com wrote: > > Almost correct. For example, in the situation where a mirror is > moving normally toward a source at velocity v, the mirror will > experience the light as arriving at c + v. Upon reflection, the light > will be traveling at c + 2v with respect to the source; and, as you > state, at c + v with respect to the mirror. > According to the Thompson Theorem of Velocity Composition c(theta)=c*sqrt(1-((v/c)sin(theta)^2)+v*cos(theta) where theta is the angle between v and c (viewed as vectors). So: c(theta=0)=c+v c(theta=pi)=c-v For a general angle, you have formula (1) Reference: O.M.Stewart The Second Postulate of Relativity and the Electromagnetic Emission Theory of Light, Phys Rev 32.418-428 (1911) Plug the above in the Sagnac ot in the Ives experiments and see that the predictions of ET contradict the experimental data.
From: Jonah Thomas on 22 Oct 2009 12:35 "Inertial" <relatively(a)rest.com> wrote: > "Jonah Thomas" <jethomas5(a)gmail.com> wrote > > "Inertial" <relatively(a)rest.com> wrote: > >> > Jonah Thomas <jethomas5(a)gmail.com> wrote: > > > >> >>Doppler shift is a change in observed frequency. > >> > >> Or wavelength .. Or both > > > > Doppler shift is a change in observed frequency. Not wavelength. I'm > > not always precise in my wording but still I want to ask you to be. > > Doppler is an effect on measured wavelength or frequency or both. You > can have Doppler shifted frequency or Doppler shifted wavelength. > > You can find some definitions talk about Doppler shift as a frequency > change http://wordnetweb.princeton.edu/perl/webwn?s=doppler%20shift > http://en.wikipedia.org/wiki/Doppler_shift > http://www.nps.gov/gis/gps/glossary.htm > > some talk about a wavelength change eg > http://www.encyclopedia.com/doc/1O80-Dopplershift.html > http://starchild.gsfc.nasa.gov/docs/StarChild/glossary_level2/glossary_text.html > http://www.nps.gov/history/history/online_books/butowsky5/astro7.htm > http://www.nrao.edu/imagegallery/glossary.shtml) > http://www.flowmeterdirectory.com/sensor_terminology_a.html > > and some about both eg > http://www.astro.bas.bg/~petrov/glossary.html > http://earthguide.ucsd.edu/virtualmuseum/Glossary_Astro/gloss_a-f.shtml > http://science.nasa.gov/newhome/help/glossary.htm > > So i think I was quite valid in saying it is an observed change in > frequency or wavelength or both. For light we find that it is both. The formula for the classical doppler effect is f = f0 * (v+vr) / (v+vs) The doppler effect is defined in terms of frequency and velocity. The formula for the relativistic doppler effect is f = f0*sqrt( (c+v)/(c-v) ) It makes sense to me that once you know the invariant lightspeed you could convert these to work for wavelength. But the definitions you quote do not give any formula at all. They are mostly worthless. Still, it does make sense that you could calculate the change in wavelength given the change in frequency, once you assume that the speed cannot change.
From: Jonah Thomas on 22 Oct 2009 12:45 "Inertial" <relatively(a)rest.com> wrote: > <tominlaguna(a)yahoo.com> wrote in message > news:0qc0e5dhbaf4vu8qhib1s6omos1cv3e8m6(a)4ax.com... > > As I understand, ballistic theory means light behaves light a > ballistic particle .. so it's velocity in some frame is the sum of the > velocity of source and that of the light wrt the source. Similarly > light would reflect from a mirror at the same speed as it hits the > mirror .. so if it hits a mirror at c+v, it will leave the mirror at > the same speed. > > So it looks like there are three possibilities for reflection. If > light hits a mirror at v+c (ie the mirror is moving toward the source > at v) then the light could be reflected with a speed of either > > 1) c+v .. if it behaves like a particle hitting a surface (eg a pool > ball bouncing off a cuschion .. the faster it hits, the faster it > bounces off) 2) c .. if it is absorbed and reemitted > 3) c-v .. no idea how this could happen, but someone the mirror knows > how to make light faster or slower as appropriate. So like rolling a > pool ball slowly at a cushion and it bounces off fast and vice versa > > To me, 1) sounds like light behaving in a 'ballistic' way. 2) does > sound like "re-emission" .. don't know WHAT one should call 3) that > isn't derogatory though :) There's a 4th possibility. 4) c + V0.Dn where V0 is the velocity of the source, and Dn is a unit vector pointing in the new direction. Some people want to say that it doesn't make sense for light to remember the velocity of its source. But various things do work kind of analogously to that. For example, an electromagnetic field created by an electric charge has one component that would be the same even if the charge was not moving, and a second component that depends on the charge's velocity. It isn't that different to have another attribute of light have two components, one that would be the same even if the source was not moving and a second component that depends on the source's velocity.
From: Androcles on 22 Oct 2009 12:48 <tominlaguna(a)yahoo.com> wrote in message news:giv0e5hgbroqllrqcq1irh35la32uj42cr(a)4ax.com... > On Thu, 22 Oct 2009 16:17:46 +0100, "Androcles" > <Headmaster(a)Hogwarts.physics_p> wrote: > >> >><tominlaguna(a)yahoo.com> wrote in message >>news:s5q0e5drrps6bngu5u314mv0mbq82srik3(a)4ax.com... >>> On Wed, 21 Oct 2009 15:33:24 +0100, "Androcles" >>> <Headmaster(a)Hogwarts.physics_p> wrote: >>> >>>> >>> [snip] >>>> >>>>Show me where. >>>> >>> [snip] >>> >>> http://www.wbabin.net/historical/silberstein1.pdf >>> http://www.wbabin.net/historical/lunn.pdf >>> http://www.wbabin.net/historical/silberstein.pdf >> >>That's better, now I have something to read. >> >>"The purpose of the present paper is to investigate some questions >>concerning light propagation in a uniformly rotating rigid system, >>such as the Earth, on both the aether theory and the relativity >>theory." -- >>Silberstein >> >>Hence we can safely conclude that emission fact is not considered >>by Silberstein. >> Seems to me that comparing two incorrect theories is waste of time, >>we are back to debating how many angels can dance on the head of >>a pin. >>I'll be more than happy to answer any questions you may have >>with respect to emission theory, or even with respect to Einstein's >>crackpottery, but I'm not about to agree with Einstein's second >>postulate which both Silberstein and Lund are doing. >> >>What was your point in raising these ancient and irrelevant documents? > > The Coriolis effect. > > I agree that both aether and SRT theories are incorrect. Ok, I did that one a long time ago. http://www.androcles01.pwp.blueyonder.co.uk/Sagnac/CoriSag.gif The neat thing about Google Sketchup is one can accurately rotate the objects and then stick the new object to it, so what you are seeing is the mathematical true path in the rotating frame, albeit highly exaggerated. The light leaves at 6 o'clock, reflects at 3 o'clock and 9 o'clock, ends at 12 o'clock. Although in phase, the wavelengths differ, so when the light continues past the beamsplitter to the detector it shows a shift which is a function of the rate of rotation. http://www.androcles01.pwp.blueyonder.co.uk/Sagnac/SagnacRing.JPG The bigot Tom Roberts stops looking at the beamsplitter and says emission fact can't work because there is no phase shift at the beamsplitter, but Sagnac doesn't have a detector at the beamsplitter, the camera is actually off the turntable. http://commons.wikimedia.org/wiki/File:Sagnac-Interferometer.png. So even if you and Jonah Thomas are taken in by his prejudice in favour of SR, he's really just another incompetent babbling fool and isn't knowledgeable at all. He's never read Einstein's paper, he advocates "Spacetime Physics", a crappy publication that skips over Einstein's faulty math.
From: paparios on 22 Oct 2009 13:04
On 22 oct, 13:35, Jonah Thomas <jethom...(a)gmail.com> wrote: > "Inertial" <relativ...(a)rest.com> wrote: > > "Jonah Thomas" <jethom...(a)gmail.com> wrote > > > "Inertial" <relativ...(a)rest.com> wrote: > > >> > Jonah Thomas <jethom...(a)gmail.com> wrote: > > > >> >>Doppler shift is a change in observed frequency. > > > >> Or wavelength .. Or both > > > > Doppler shift is a change in observed frequency. Not wavelength. I'm > > > not always precise in my wording but still I want to ask you to be. > > > The formula for the classical doppler effect is > > f = f0 * (v+vr) / (v+vs) > > The doppler effect is defined in terms of frequency and velocity. > > The formula for the relativistic doppler effect is > > f = f0*sqrt( (c+v)/(c-v) ) > > It makes sense to me that once you know the invariant lightspeed you > could convert these to work for wavelength. > > But the definitions you quote do not give any formula at all. They are > mostly worthless. Still, it does make sense that you could calculate the > change in wavelength given the change in frequency, once you assume that > the speed cannot change. At least when I was at the high school, we were told that the wavelength (\lambda) and the frequency (f) were related with the speed (v) with the formula: \lambda=v/f, which, for the case of light, reads as \lambda=c/f Miguel Rios |