Ballistic theory of light demolished
in [Relativity]
|
From: blackhead on 31 Jul 2010 19:34 On 31 July, 23:31, ..@..(Henry Wilson DSc) wrote: > On Fri, 30 Jul 2010 19:13:28 -0700 (PDT), blackhead <larryhar...(a)softhome..net> > wrote: > > > > > > >On 30 July, 23:38, ..@..(Henry Wilson DSc) wrote: > >> On Fri, 30 Jul 2010 08:59:58 -0500, Tom Roberts <tjroberts...(a)sbcglobal.net> > >> wrote: > > >> >Henry Wilson DSc wrote: > >> >> On Thu, 29 Jul 2010 16:23:48 -0700 (PDT), Uncle Ben <b...(a)greenba.com> wrote: > > >> >>> On Jul 29, 6:19 pm, ..@..(Henry Wilson DSc) wrote: > >> >>>> On Wed, 28 Jul 2010 21:46:41 -0700 (PDT), Uncle Ben <b...(a)greenba..com> wrote: > >> >>>>> There are those saying that the speed of light depends on the speed of > >> >>>>> the source. This explains the MMX experiment neatly, but the theory > >> >>>>> has now been refuted experimentally. > >> >>>>> Let the speed of light emitted by a source moving at speed v be c + > >> >>>>> kv, where k is to be determined experimentally. The theory propounded > >> >>>>> by Androcles, NoEinstein and others in this newsgroup implies that > >> >>>>> k=1. Einstein proposed that k=0. > >> >>>>> The following account is copied from the collection of experimental > >> >>>>> papers on SR at > >> >>>>>http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html#... > >> >>>>> --------------------------------------------------------------------------------------------- > >> >>>>> Operation of FLASH, a free-electron laser,http://vuv-fel.desy.de/. > >> >>>>> A free-electron laser generates highly collimated X-rays parallel to > >> >>>>> the relativistic electron beam that is their source. If the region > >> >>>>> that generates the X-rays is L meters long, and the speed of light > >> >>>>> emitted from the moving electrons is c+kv (here v is essentially c), > >> >>>>> then at the downstream end of that region the minimum pulse width is > >> >>>>> k(L/c)/(1+k), because light emitted at the beginning arrives before > >> >>>>> light emitted at the downstream end. For FLASH, L=30 meters, > >> >>>>> v=0.9999997 c (700 MeV), and the observed X-ray pulse width is as > >> >>>>> short as 25 fs. This puts an upper limit on k of 2.5×10-7. Optical > >> >>>>> extinction is not present, as the entire process occurs in very high > >> >>>>> vacuum. > >> >>>>> ---------------------------------------------------------------------------------------- > >> >>>>> k <= 0.00000025 > >> >>>>> Einstein wins decisively. > >> >>>>> Uncle Ben > >> >>>> Pathetic....as usual. > > >> >>>> The X-rays are emitted when the electrons interact with occasional gas > >> >>>> molecules.....whose v>>0 wrt the apparatus frame. > > >> >>>> Henry Wilson... > > >> >>> Nope. It is a very high vacuum. No extinction. > > >> >> Pathetic, as usual. > > >> >> The vacuum might be high enough to avoid extinction but it is not high enough > >> >> to prevent the occasional interaction. > > >> >Such "occasional interactions" do indeed occur, but do not account for this: the > >> >rest of the accelerator has SIMILAR (VERY LOW) DENSITIES OF GAS, but the > >> >coherent x-rays are emitted ONLY when the beam is in the magnetic wiggler. > > >> I can't see any reference in the experiment to your claims. > > >> How and why are the x-rays formed and who measured their speeds? > > >Accelerated charge generates EM radiation. The wiggler "wiggles" and > >so changes the direction of the electrons, causing them to radiate. > >The speed of the electrons is what matters in this experiment. Here's > >a link to a wiggler: > > >http://en.wikipedia.org/wiki/Wiggler_(synchrotron) > > >> There is no reason why the x-ray pulse width should depend on the (constant) > >> electron speed. X-rays are emitted over a certain electron travel time > >> interval, around (L/c). They will arrive at a detector over the same time > >> interval even if they move at 100c. > > >Suppose you had just one electron entering the wiggler. The front end > >of the pulse is generated when the electron enters the wiggler, the > >back end when it leaves. If the front end of the pulse travels at the > >same velocity as the electron, then the back end will be generated > >where the electron and the front end of the pulse is, giving a pulse > >width of zero. > > >A wiggler has a length of the order of meters, with electrons > >travelling around 1 meter per 3ns, yet the pulse width is of the order > >fs. This would imply the X-rays travel close to the speed of the > >electrons, don't you think? > > Pathetic > > You seem to be suggesting that the x-rays have a preferred direction. EM radiation does have a preferred direction, if you look at the acceleration term in the Lienard-Wiechert fields for a charge. > Henry Wilson... > > .......Einstein's Relativity...The religion that worships negative space.- Hide quoted text - > > - Show quoted text -
From: Jerry on 1 Aug 2010 02:47 On Jul 30, 5:38 pm, ..@..(Henry Wilson DSc) wrote: > On Fri, 30 Jul 2010 08:59:58 -0500, Tom Roberts <tjroberts...(a)sbcglobal.net> > wrote: > >Such "occasional interactions" do indeed occur, but do not account for this: the > >rest of the accelerator has SIMILAR (VERY LOW) DENSITIES OF GAS, but the > >coherent x-rays are emitted ONLY when the beam is in the magnetic wiggler. > > I can't see any reference in the experiment to your claims. That is because you haven't searched. > How and why are the x-rays formed and who measured their speeds? Most of my knowledge about free electron lasers comes from having visited a library and actually read books, but a few online resources are available: http://cas.web.cern.ch/cas/Pruhonice/PDF/Renieri.pdf http://en.wikipedia.org/wiki/Free_electron_laser The key to understanding how FELS lasing occurs comes from understanding the special undulator design, first proposed by Hans Motz and realized in practice by John Madey. In this form of undulator, random shot noise initially causes the electrons to bunch up into vaguely defined groups spaced by the predominant wavelength of the emitted light. Light whose wavelength equals that of the electron spacing will add up coherently, and the coherently emitted light causes the electron bunches to be more tightly defined, a self-reinforcing process that results in an intense beam of coherent light in the transverse direction. FELS lasing requires that the electrons be moving at relativistic speeds. The lasing mechanism could not -possibly- occur if light were ballistic. > There is no reason why the x-ray pulse width should depend on the (constant) > electron speed. X-rays are emitted over a certain electron travel time > interval, around (L/c). They will arrive at a detector over the same time > interval even if they move at 100c. > > As usual, the relativist logic is wrong. You need a repeat of my earlier post? Consider a 10 fs pulse of electrons * traveling through the undulator at v=0.9999997 c, with X-rays |||| being continually emitted by the electrons as they wiggle through the undulator. Let k=1, i.e. photons are being emitted at 2c E----------------------------F *| electrons have traveled 1m, front of X-ray beam 2m *|| electrons have traveled 2m, front of X-ray beam 4m *||| electrons have traveled 3m, front of X-ray beam 6m *|||| electrons have traveled 4m, front of X-ray beam 8m etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. *|||||||||||||||||||||||||||| *||||||||||||||||||||||||||||| *|||||||||||||||||||||||||||||| Difference between front and rear of 2c X-ray beam = 30 m Total X-ray pulse duration = 10 fs + 30 m/(2c) = 50 ns ======================================================= Let k = 0.1, i.e. photons are being emitted at 1.1c E----------------------------F *||| Difference between front and rear of 1.1c X-ray beam = 3 m Total x-ray pulse duration = 10 fs + 3 m/(1.1c) = 9.1 ns ======================================================= Let k = 0, i.e. photons are being emitted at c E----------------------------F *| Since the electrons are traveling at 0.9999997c, the difference between front and rear of the 1c X-ray beam = 9 um Total X-ray pulse duration = 10 fs + 9 um/c = 40 fs Jerry
From: Androcles on 1 Aug 2010 04:35 "Jerry" <Cephalobus_alienus(a)comcast.net> wrote in message news:46d1c9e5-770e-416a-94ed-3df399afcd35(a)l17g2000vbf.googlegroups.com... | On Jul 30, 5:38 pm, ..@..(Henry Wilson DSc) wrote: | > On Fri, 30 Jul 2010 08:59:58 -0500, Tom Roberts <tjroberts...(a)sbcglobal.net> | > wrote: | | > >Such "occasional interactions" do indeed occur, but do not account for this: the | > >rest of the accelerator has SIMILAR (VERY LOW) DENSITIES OF GAS, but the | > >coherent x-rays are emitted ONLY when the beam is in the magnetic wiggler. | > | > I can't see any reference in the experiment to your claims. | | That is because you haven't searched. | | > How and why are the x-rays formed and who measured their speeds? | | Most of my knowledge about free electron lasers comes from having | visited a library and actually read books, but a few online | resources are available: | http://cas.web.cern.ch/cas/Pruhonice/PDF/Renieri.pdf | http://en.wikipedia.org/wiki/Free_electron_laser | | The key to understanding how FELS lasing occurs comes from | understanding the special undulator design, first proposed by | Hans Motz and realized in practice by John Madey. In this form | of undulator, random shot noise initially causes the electrons to | bunch up into vaguely defined groups spaced by the predominant | wavelength of the emitted light. Light whose wavelength equals | that of the electron spacing will add up coherently, and the | coherently emitted light causes the electron bunches to be more | tightly defined, a self-reinforcing process that results in an | intense beam of coherent light in the transverse direction. | | FELS lasing requires that the electrons be moving at relativistic | speeds. The lasing mechanism could not -possibly- occur if light | were ballistic. | | > There is no reason why the x-ray pulse width should depend on the (constant) | > electron speed. X-rays are emitted over a certain electron travel time | > interval, around (L/c). They will arrive at a detector over the same time | > interval even if they move at 100c. | > | > As usual, the relativist logic is wrong. | | You need a repeat of my earlier post? | | Consider a 10 fs pulse of electrons * traveling through the | undulator at v=0.9999997 c, with X-rays |||| being continually | emitted by the electrons as they wiggle through the undulator. | | Let k=1, i.e. photons are being emitted at 2c As usual, the relativist logic is wrong, the undulator doesn't move at c. Why should it emit photons at twice nothing?
From: Jerry on 1 Aug 2010 15:19 On Aug 1, 3:35 am, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > As usual, the relativist logic is wrong, the undulator doesn't move at c. > Why should it emit photons at twice nothing? Wrong. Check out the Lienard-Wiechert potential: http://en.wikipedia.org/wiki/Li%C3%A9nard-Wiechert_potential This describes the electromagnetic effect of a moving charge. Scroll down the article a bit. It is a time-dependent integral over charge density. In other words, only the motions of the charges matter. Other fields do not enter into the equation. In other words, EM is generated when you wiggle a bunch of electrons. It doesn't matter -how- you wiggle them. A typical method is to connect an antenna to the output of an RLC resonant circuit. The antenna doesn't need a magnetic field to operate correctly. EM is not emitted by the non-existent magnetic field in which the antenna does not operate. You could also stick a charged pith ball to the end of a ruler and wave it. EM is emitted by accelerated electrons in the pith ball. It is not emitted by the non-existent magnetic field in which you are not waving the ruler. In an accelerator undulator, EM is emitted by the accelerating electrons. Magnets are important only in so far as they are the means by which you are accelerating the electrons. But the Lienard-Wiechert equation tells us that it is the electrons that are doing the emitting, not the static magnetic field that is forcing the electrons to wiggle. If you disagree with the above, then you need to supply a replacement for Maxwell's equations. Good luck. Jerry
From: Jerry on 1 Aug 2010 15:39
On Aug 1, 1:47 am, Jerry <Cephalobus_alie...(a)comcast.net> wrote: > Most of my knowledge about free electron lasers comes from having > visited a library and actually read books, but a few online > resources are available:http://cas.web.cern.ch/cas/Pruhonice/PDF/Renieri.pdfhttp://en.wikipedia.org/wiki/Free_electron_laser > > The key to understanding how FELS lasing occurs comes from > understanding the special undulator design, first proposed by > Hans Motz and realized in practice by John Madey. In this form > of undulator, random shot noise initially causes the electrons to > bunch up into vaguely defined groups spaced by the predominant > wavelength of the emitted light. Light whose wavelength equals > that of the electron spacing will add up coherently, and the > coherently emitted light causes the electron bunches to be more > tightly defined, a self-reinforcing process that results in an > intense beam of coherent light in the transverse direction. > > FELS lasing requires that the electrons be moving at relativistic > speeds. The lasing mechanism could not -possibly- occur if light > were ballistic. Since the coherently emitted light travels at c, and the electrons travel at nearly c, the coherently emitted light remains CONCENTRATED in the immediate vicinity of the electron pulse, resulting in high field densities that force the electrons to bunch up into groups spaced according to the wavelength of the coherently emitted light in the positive feedback loop described above. If light were ballistic, this self-reinforcing process could not occur. Any emitted light would immediately exit the electron pulse and the positive feedback loop described above could not occur. The very -existence- of free electron lasers disproves ballistic theory. Jerry |