Wang / Sagnac Devices
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From: Sam on 25 Oct 2009 01:00 On Oct 24, 7:55 pm, Sam <shay...(a)yahoo.com> wrote: > ...the particles continue to move at c relative to > the "original source" at the time they were emitted. > However, this hypothesis leads again to a prediction > of zero Sagnac effect... Correction: That hypothesis is essentially equivalent to an ether theory, in which the corresponding light pulses propagate at c relative to a single fixed frame of reference as the device rotates. Calling this a "ballistic" theory is surely a misnomer. It is, at most, a semi-ballistic theory, but in order for such a theory to be meaningful, it must specify what distinguishes between an emission and a reflection. In most theories of light, reflection consists of absorption and re-emission. For example, if an atom in a lamp filament is in a high energy level and drops to a lower energy level and emits some light, we would probably call this an emission, but if this light hits an atom somewhere else (like a mirror), raises that atom to a higher energy level, and then it drops back down and emits some light, is this also an emission? If so, then Sagnac refutes it. If not, then it's difficult to rationalize why some emissions are to be treated as emissions, whereas others are to be treated as reflections, i.e., as a completely different physical process, with very different properties for the light. This is especially tricky because a single atom could both be emitting light and absorbing-reflecting light, and both processes consist of changing from one energy level to another. So are we really to take seriously the idea that some of the light is to be treated as a primitive emission while some is to be treated completely differently, subject to a completely different law? Also, the reflected light must remain "entangled", not with the emitter now, but with the emitter at the past moment of emission, even after the light has (potentially) been reflected arbitrarily many times in many different directions - it still somehow "remembers" the state of motion of its "original source". If we're willing to entertain this possibility, we might as well trace all energy back to the same original source, and argue that all subsequent interactions have just been "reflections", and hence all light propagates at c relative to the very same fixed primal frame of reference, i.e., we have a fixed ether theory. Calling this a ballistic theory is surely misleading. If we don't go that far, and merely insist that light "remembers" only a limited number of past interactions, then we have a total mis-mash with no predictive power, because we can never identify the "original" source of any give pulse of light, so we have no way, a priori, of knowing how fast to expect the light to propagate. When calling such things a "ballistic theory", not only is the word "ballistic" a misnomer, but so is the word "theory".
From: Jerry on 25 Oct 2009 01:09 On Oct 24, 11:32 pm, Darwin123 <drosen0...(a)yahoo.com> wrote: > On Oct 22, 2:53 am, Jonah Thomas <jethom...(a)gmail.com> wrote: > > The reason I predict that will have no effect is that the traditional > > Sagnac explanation (the one that says the detector moves so that the > > light paths are in proportion c+v:c-v) gives the right answer. >It does > > not depend in any way on the movement of the mirrors along the path, but > > only on the movement of the detector. If you get the same effect by > > moving the mirrors and leaving the detector alone, then this explanation > > gives the correct result entirely by accident. > I don't follow. > > It could be true that > > this explanation is not only wrong but has no relation whatsoever to the > > correct explanation, > > Okay, I am lost. I have no idea what you are saying. Maybe it is > my lack of comprehension. However, I can't envision what you are > talking about. Thanks for talking, though |:-) I think what Jonah is talking about has something to do with Androcles' belief (former belief???) that the detector is mounted beside the rotating table, not on the rotating table itself. Various of Jonah's comments indicate that he is confused on this point. Jerry
From: tominlaguna on 25 Oct 2009 02:39 On Sun, 25 Oct 2009 00:19:21 +0100, "Androcles" <Headmaster(a)Hogwarts.physics_p> wrote: > >"Henry Wilson DSc ." <HW@..> wrote in message >news:o307e5hce7ic1g0mopcv46so92a7ipmjnr(a)4ax.com... >> On Sat, 24 Oct 2009 12:43:01 +0100, tominlaguna(a)yahoo.com wrote: > >>>And, surprise surprise the 2v value appears. It is the same value >>>that appears in the Doppler radar formula. So could it be that every >>>traffic cop with a radar gun is validating the Ballistic theory with >>>each speeding ticket issued? >>> >>>B. Equation 74 looks vaguely familiar... Oh yes, it's the equation >>>for Snell's Law! Tom Roberts claimed that the Ballistic theory >>>violated Snell's Law and therefore was not consistent with the Sagnac >>>Effect. That appears not to be the case, does it? >>> >>>I think the bigger issue for Tom Roberts is to find a SRT-consistent >>>formulation for the angle of reflection from a moving mirror. I cited >>>two different equations for the angle of reflection by mainstream >>>physics authors. I know if I do some digging, I will come up with >>>other variations. This issue could be interesting to follow. >> >> This analysis is OK > > >No it isn't. The moving transponder can only emit at c and the photon >can only hit the cop at c+v, not c+2v as La Goona Tommy is claiming. >You are not paying attention, you've got one eye on the Shiraz and >gout on the brain. I've made no such claim. The signal arrives back at the cop at a speed of c+v in this scenario as you state, but its frequency has been altered by a factor relating to 2v. Its frequency was changed first when it met a moving receiver and altered a second time when it was sent back by a moving emitter. Instead of getting tangled up with 2v, think of it as 2*(v/c). That being said, I have got to admit that you made a brilliant observation in one of your earlier posts that I nearly overlooked. You said something to the effect that I was using Doppler equations that were based on Aether theory. You are right. The physical modelling of Doppler needs to be modified. I am quite sure you will arrive at the same mathematical relationships but for different reasons. The current assumptions are that wavelengths change but speed remains constant. In the Ballistic model, speed varies but wavelength remains constant. > if light is treated like an elastically bouncing ball. It >> is not. >> A photon takes time to be emitted and consequently possesses >> length....maybe >> billions of 'wavelengths'. > > >Oh my gawd... he's back to his headless crocodiles again... >That gout must be really troubling you, all the wine barrels are >empty. >
From: Jonah Thomas on 25 Oct 2009 02:57 Sam <shayiam(a)yahoo.com> wrote: > Jonah Thomas <jethom...(a)gmail.com> wrote: > > It concerns me that for some 70 years before we > > had fiber optic cables to do the experiment, many people > > claimed that Sagnac refuted any ballistic theory, when > > they did not. > > That's a complicated assertion to unpack, because (for example) one > might regard quantum electrodynamics in Minkowski spacetime (special > relativity) as a "ballistic" or "emission" theory. So, in that sense, > the Sagnac effect obviously doesn't refute every possible theory that > someone might choose to label as an "emission theory". > When people say that the Sagnac effect rules out every ballistic > theory it is usually understood that they are referring to a theory in > Galilean space and time in which light behaves "more or less" like > small material particles in Newtonian mechanics, emitted at the speed > c relative to the emitting object, and reflecting off other objects > like perfectly elastic particles. The Sagnac effect obviously refutes > this class of theories, because they predict zero effect. Bear with me on this. I might be wrong, but my argument is simple and ought to be easy to understand. Until we had laser cavities that sent the same light in opposite directions, physicists who did the Sagnac experiment always started with a single light source and then used a beam-splitter etc to convert it into two separate beams of light. If a ballistic theory predicts that the speed of light depends on the speed of its source, then in every early Sagnac experiment the light went the same speed in two different directions, according to an inertial observer. When the light is emitted it is one light beam emitted in one direction. The only way to get a change in lightspeed in that experiment comes if somehow mirrors bounce light at different speeds, or a change in direction changes the speed, etc. Simple straighforward ballistic theories would say that the light travels at the same speed relative to an inertial observer, so the light in one direction arrives sooner than the light from the other direction, and the difference in arrival time would be essentially the same as that predicted by other theories. Since this class of theories does not predict zero effect it is not refuted by Sagnac. Now we have lasers that push light in two opposite directions. Align those with the direction of travel and ballistic theories should predict the light will travel at c+v and c-v, relative to an inertial observer. But before those were available -- 60 years? 70 years? -- the majority of physicists said that Sagnac refuted ballistic theories when it obviously did not. Why were they so sloppy? Perhaps they were not interested in ballistic theories so they were ready to just slide by them. Perhaps some other experiment really did refute all ballistic theories, and physicists did not care whether Sagnac was falsely claimed to refute them because they were known to be false regardless. > In general, any serious theory that has been called a "ballistic" or > "emission" theory by its proponents is refuted by the Sagnac effect. That used to be false, for the large majority of the years that it was claimed. With fiber optics and lasers that create light that travels in opposite directions and still interferes, it might easily be true now.
From: Androcles on 25 Oct 2009 03:19
"Sam" <shayiam(a)yahoo.com> wrote in message news:76ddae7d-26be-4d37-9070-9ef5469cbd78(a)k26g2000vbp.googlegroups.com... On Oct 23, 7:46 pm, Jonah Thomas <jethom...(a)gmail.com> wrote: > It concerns me that for some 70 years before we > had fiber optic cables to do the experiment, many people > claimed that Sagnac refuted any ballistic theory, when > they did not. That's a complicated assertion to unpack, because (for example) one might regard quantum electrodynamics in Minkowski spacetime (special relativity) as a "ballistic" or "emission" theory. So, in that sense, the Sagnac effect obviously doesn't refute every possible theory that someone might choose to label as an "emission theory". When people say that the Sagnac effect rules out every ballistic theory it is usually understood that they are referring to a theory in Galilean space and time in which light behaves "more or less" like small material particles in Newtonian mechanics, emitted at the speed c relative to the emitting object, and reflecting off other objects like perfectly elastic particles. The Sagnac effect obviously refutes this class of theories, =============================================== You are OBVIOUSLY an idiot! http://www.androcles01.pwp.blueyonder.co.uk/Sagnac/Sagnac.htm |