Speed of Light: A universal Constant?
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From: George Dishman on 6 Apr 2005 18:36 "Henri Wilson" <H@..> wrote in message news:65g851dn7asmetb67jjv5cnue56cbsjlai(a)4ax.com... > On Wed, 6 Apr 2005 19:51:08 +0100, "George Dishman" > <george(a)briar.demon.co.uk> > wrote: > >> >>"Henri Wilson" <H@..> wrote in message >>news:dmq6515nh5ja7it6sljt6bvibl68a7otu3(a)4ax.com... >>> On Tue, 5 Apr 2005 23:51:10 +0100, "George Dishman" >>> <george(a)briar.demon.co.uk> >>> wrote: >>> >>>>Henri, there's a lot we have agreed. I've >>>>trimmed most out to get the size down. <more trimmed> >>>>Let me try another way to express this, perhaps >>>>you can agree this approach instead. I'll be a >>>>bit vague about the details but hopefully you'll >>>>allow me a little leeway. Take a point source S >>>>and a screen and create fringes by reflecting >>>>the source off a mirror M onto the screen as >>>>well as the direct beam. I've shown the beams >>>>as lines though they would need to illuminate >>>>most of the screen as usual: >>>> >>>> >>>> X S >>>> /| >>>> / | >>>> M / | >>>> R__|/ | >>>> |\ | >>>> \ | >>>> \A| >>>> \| >>>> ---+-- >>>> D >>>> screen >>>> >>>>There is a detector at point D on the screen and >>>>the reflected beam hits the mirror at point R >>>>and the angle between the beams is A at that >>>>point. >>>> >>>>So far, so good. >>>> >>>>Now suppose we move and tilt the mirror such that >>>>the point where the light reflects moves along an >>>>ellipse with S and D as its foci. The path length >>>>from S via R to D will remain the same but the >>>>angle A will change. What I am saying is that the >>>>brightness at the detector will be unchanged even >>>>though the angle is changing. What will be >>>>affected is the fringe spacing either side of the >>>>detector but that is because the path length >>>>anywhere else cannot be held constant as well as >>>>that to point D. >>>> >>>>Now consider the converse, suppose we move the >>>>mirror along the line from D to X (top left) >>>>again tilting the mirror as required to keep >>>>the point of reflection exactly on the X-D line. >>>>This time there will be a change of brightness >>>>at D due to the change of path length even though >>>>the angle A is being held constant. >>> >>> I undestand the experiment but I cannot see how it >>> relates to the problem. >> >>The question is do you agree with it or do we >>need to spend more time investigating? >> >>It should demonstrate that a change of angle >>as illustrated in the case of the elliptical >>motion has no effect on the brightness as long >>as the path length of both beams remains the >>same while path length does have an effect even >>if the angle remains constant. > > In the elliptical case, the intensity of the beam will remain constant > only in > a plane perpendicular to the beam direction. Note I am describing the intensity only at a single point. In other situations that may extend to other points by symmetry but not in this case. > In your example, a cosine > correction needs to be applied to compare intensities AT ANY POINT on the > target. > I'm not sure if tat is relevant. It might only affect the contrast of the > fringes. What is significant is that it shows that the angle at which the light arrives at point D is unimportant, hence any possible angle change in the Sagnac case is also unimportant, except insofar as it might lead to a path length change. >>You said "In my sagnac model, there is both >>sideways displacement AND angular change." but, >>if you agree, you should now understand that a >>change of angle cannot cause any effect at the >>detector. >> > But there is also a path length difference. RThat's the key and her I agree with you, but my point is that the effect must come from the length change only, not the angle change, hence that makes it a lot easier to calculate. > 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'm sure we are close to a mutual understanding. >>> >>> Not all that close yet. >> >>Shame. OK, what argument can you offer that >>my gedankens are wrong if you disagree? > > What I just stated above. There is both a path difference and an angular > change. Yes but my point was that only the path length change creates a brightness change at point D, I wasn't saying anything about Sagnac yet. If you agre the points above, then we can move on to use them in the analysis. >>http://www.javatester.org/version.html >> >>It also gives links for getting the Sun >>version such as this: >> >>http://www.java.com/en/download/ > > Their web page is as hard to understand as their program. Yes, the JavaTester page makes that point. All I did was click the java.com link then click the "Begin Download" button and accept all the defaults and it worked. >>I just followed the defaults and it >>worked fine. >> >>>>If it works, switch on one beam at a time >>>>using the check boxes and move the location >>>>of the detector using the slider. Wiggle it >>>>about and see if you agree with the beam >>>>paths. Then switch both on and look at the >>>>angle between the beams at the detector. Let >>>>me know what you think. >>> >>> Have another attempt. >> >>The program seems OK having tested from >>another site. If you install the JVM from >>Sun, it should solve the problem. > > My Java was not enabled but your applet still wont appear. Odd, the JavaTester site may help http://www.javatester.org/version.html >>> I gave up on Java. There has to be an easier way. >>> >>> Visual basic is SO simple. >> >>It is, but you have to pay for it :-( > > True > >> >>The Java SDK is free :-) > > But the free version is very difficult to use. True, I found the display elements tedious but Swing helps and the EJS program does all that for you. Anyway, let's get the simulation running so we can address the Sagnac case, the software is only a means to that end. > Java code itself is pretty easy. > Getting the thing to run is the hard part > > My daughter who is a programer is currectly learning Java. She agrees it > is > very confusing and hard to use. Maybe she can see why your JVM isn't working. I had installed ages ago on my home machine but the install I did today was straight from the site on a bog-standard IE6 machine. George
From: The Ghost In The Machine on 7 Apr 2005 02:00 In sci.physics, H@..(Henri Wilson) <H@> wrote on Wed, 06 Apr 2005 05:33:48 GMT <evs651539amj4j22e859p0euniifcdttrq(a)4ax.com>: > On Tue, 05 Apr 2005 08:00:03 GMT, The Ghost In The Machine > <ewill(a)sirius.athghost7038suus.net> wrote: > >>In sci.physics.relativity, H@..(Henri Wilson) >><H@> >> wrote >>on Tue, 05 Apr 2005 05:52:39 GMT >><9o9451lcsp6cckqqqtve3iolli1j05kele(a)4ax.com>: >>> On Tue, 05 Apr 2005 03:00:08 GMT, The Ghost In The Machine >>> <ewill(a)sirius.athghost7038suus.net> wrote: > >>> >>> So when light leaves a remote star somewhere out >>> in space, that light is automatically moving at c >>> wrt every other body in the universe, is it Ghost? >>> >>> You really make the most outrageous claims, Ghost. >> >>If you think that's outrageous, try this one. >> >>A light quanta can be everywhere within the subarea of >>the 4-dimensional Universe defined by the equation >> >>(x - x_0)^2 + (y - y_0)^2 + (z - z_0)^2 - c^2 * (t - t_0)^2 = 0 >> >>which can be construed as an expanding sphere, if one >>conventionally takes t as time. If one observes this >>wavefront from another vantage point (e.g., a moving >>spacecraft) it will *still be an expanding sphere*. >>It won't be squished, distorted, or otherwise mangled. >>It might move its center, but that's about it. >> >>In any event, SR is quite clear: all observers will see that >>pulse of light traveling at the same velocity. It won't >>be the same frequency, however. > > That's just aether theory in which the one absolute frame > is replaced by an arbitrary one. > > It is completely unproven. And c' = c+v has been disproven, experimentally. > >> >>> >>>> >>>>> >>>>> Can you put two and two together Ghost? >>>> >>>>I already did. >>>> >>>>Depending on the units of "two", one gets rather odd results, >>>>but they can be expressed as >>>> >>>>2 * two / (1 + (two)^2/c^2) >>> >>> You are obsessed.! >> >>No, just being slightly silly. Don't you recognize the SR >>velocity addition formula? :-) > > Of course I did. > >> >>[rest snipped] > > Ghost, why did you snip my question? Was it too hard to answer. > Here it is again: > > Do you claim that light emitted from a remote star is initially > traveling at c relative to every object in the universe? Initially, terminally, and at every point in between. > Does that require an infinite number of discreet speeds? No. The Lorentz spacetime twist takes care of that. Herewith the math. Very hairy grody grumpy weedy math. Bring your own machete. :-) The Lorentz, of course, can be expressed x_A = (x_O - v * t_O) * g y_A = y_O z_A = z_O t_A = (t_O - v * x_O / c^2) * g where g = 1/sqrt(1 - v^2/c^2), or g^2 = 1/(1 - v^2/c^2). This will be an important observation later on. Let a dual lightcone [*] erupt at a certain point (x_o, y_o, z_o, t_o) somewhere in O-space, satisfying the equation 0 = (x_O - x_o)^2 + (y_O - y_o)^2 + (z_O - z_o)^2 - c^2 * (t_O - t_o)^2 If we do the substitution and then factor out g^2, we get: 0 = ((x_A - v * t_A) * g - x_o)^2 + (y_A - y_o)^2 + (z_A - z_o)^2 - c^2 * ((t_A - v * x_A/c^2)*g - t_o)^2 = ((x_A - v * t_A) - x_o/g)^2 * g^2 + (y_A - y_o)^2 + (z_A - z_o)^2 - c^2 * ((t_A - v * x_A/c^2) - t_o/g)^2 * g^2 = (x_A^2 + v^2 * t_A^2 + x_o^2/g^2 - 2*x_A*v*t_A - 2*x_A*x_o/g + v*t_A*x_o/g) * g^2 + (y_A - y_o)^2 + (z_A - z_o)^2 + (- t_A^2 * c^2 - v^2 * x_A^2/c^2 - c^2 * t_o^2/g^2 + 2 * t_A *v * x_A + 2 * t_A * t_o * c^2/g - 2 * v * x_A * t_o / g ) * g^2 = (x_A^2 * (1 - v^2/c^2) - 2 * x_A * (x_o - v * t_o) /g + (x_o - v * t_o)^2) * g^2 + (y_A - y_o)^2 + (z_A - z_o)^2 + (- c^2 * t_A^2 * (1 - v^2/c^2) + 2 * t_A * (t_o - v * x_o/c^2) * c^2/g - c^2 * (t_o - v * x_o/c^2)^2) * g^2 + (x_o^2/g^2 - 2*x_A*v*t_A - c^2 * t_o^2/g^2 + 2 * t_A *v * x_A) * g^2 = (x_A^2 - 2 * x_A * (x_o - v * t_o)*g + (x_o - v * t_o)^2 * g^2) + (y_A - y_o)^2 + (z_A - z_o)^2 - c^2 * (t_A^2 - 2 * t_A * (t_o - v * x_o/c^2) *g + (t_o - v * x_o/c^2)^2 * g^2) + (x_o^2/g^2 - 2*x_A*v*t_A - c^2 * t_o^2/g^2 + 2 * t_A *v * x_A - (x_o - v * t_o)^2 + c^2 * (t_o - v * x_o/c^2)^2 ) * g^2 = (x_A - (x_o - v * t_o)*g))^2 + (y_A - y_o)^2 + (z_A - z_o)^2 - c^2 * (t_A - (t_o - v*x_o/c^2)*g) + (x_o^2/g^2 - c^2 * t_o^2/g^2 - (x_o - v * t_o)^2 + c^2 * (t_o - v * x_o/c^2)^2 ) * g^2 = (x_A - x_a)^2 + (y_A - y_o)^2 + (z_A - z_o)^2 - c^2 * (t_A - t_a)^2 + (x_o^2/g^2 - c^2*t_o^2/g^2 - (x_o - v * t_o)^2 + c^2 * (t_o - v * x_o/c^2)^2 ) * g^2 = (x_A - x_a)^2 + (y_A - y_o)^2 + (z_A - z_o)^2 - c^2 * (t_A - t_a)^2 + (x_o^2/g^2 - c^2 * t_o^2/g^2 - x_o^2 - v^2*t_o^2 + 2*x_o*v*t_o + c^2 * t_o^2 + v^2 * x_o^2/c^2 - 2 * t_o * v * x_o) ) * g^2 = (x_A - x_a)^2 + (y_A - y_o)^2 + (z_A - z_o)^2 - c^2 * (t_A - t_a)^2 + (x_o^2*(1 - v^2/c^2) - c^2 * t_o^2 * (1 - v^2/c^2) - x_o^2*(1 - v^2/c^2) - v^2*t_o^2 + 2*x_o*v*t_o + c^2 * t_o^2 + 2 * t_o * v * x_o) ) * g^2 = (x_A - x_a)^2 + (y_A - y_o)^2 + (z_A - z_o)^2 - c^2 * (t_A - t_a)^2 + 0 where I've written x_a = (x_o - v * t_o) * g and t_a = (t_o - v * x_o/c^2) * g , as that part of the equation stopped contributing to the final result. If one wants to get pedantic one can define y_a = y_o and z_a = z_o, and rewrite the final result accordingly. The dual lightcone is invariant (except for a in retrospect very obvious translation) under the Lorentz. Therefore lightspeed is c everywhere under the Lorentz. I'm not sure this is proof of much, of course, beyond the fact that the math is internally self-consistent. However, it does show that it is possible to define a Universe with a metric (namely, the Minkowski) which gives OWLS=c everywhere under the Lorentz transformation. > > 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. [*] an appropriate 3-dimensional projection would look like the surface of two cones joined at their apex. This is of course a variant of the Minkowski metric -- and to a human viewer will look like an expanding sphere. -- #191, ewill3(a)earthlink.net It's still legal to go .sigless.
From: Jim Greenfield on 7 Apr 2005 02:11 "PD" <pdraper(a)yahoo.com> wrote in message news:<1112798142.810841.160810(a)g14g2000cwa.googlegroups.com>... > Jim Greenfield wrote: > > "PD" <pdraper(a)yahoo.com> wrote in message > news:<1112731023.977565.318940(a)z14g2000cwz.googlegroups.com>... > > > Jim Greenfield wrote: > > > > The Ghost In The Machine <ewill(a)sirius.athghost7038suus.net> > wrote in > > > message news:<l9a9i2-f6i.ln1(a)sirius.athghost7038suus.net>... > > > > > In sci.physics, H@..(Henri Wilson) > > > > > <H@> > > > > > wrote > > > > > on Mon, 04 Apr 2005 21:31:29 GMT > > > > > <u6c351du1rm845dlvhj309smegtid0gnm9(a)4ax.com>: > > > > > > On Mon, 4 Apr 2005 12:09:32 +0000 (UTC), bz > > > <bz+sp(a)ch100-5.chem.lsu.edu> wrote: > > > > > > > > > > > >>H@..(Henri Wilson) wrote in > > > news:gh4251dpkork18r2kknvn2gu6lt979b8m3@ > > > > > >>4ax.com: > > > > > >> > > > > > >>> Ghost, is not velocity always specified relative to > something? > > > > > >>> > > > > > >>> Is not the speed of light always 'c' wrt its source? > > > > > >>> > > > > > >>> > > > > > >> > > > > > >>The velocity of light is always c with respect to the > observer. > > > > > > > > > > > > Proof please! > > > > > > > > > > No proof available. At best, there are several experiments > > > > > that show evidence for this statement, a number of indirect > > > > > experiments that show evidence for related concepts, and > > > > > a number of observations of astrophysical phenomena that > > > > > show evidence for other related concepts given certain > > > > > assumptions. > > > > > > > > Primary assumption that has mired physics / astronomy for decades > > > > being that > > > > Doppler is falsely attributed to a magical wavelength alteration, > > > thus > > > > skewing > > > > many measurements as to distance, velocity and composition > (spectra) > > > > > > And this shows you know nothing about how light's wavelength is > > > measured. One approach that's been around for years is the > diffraction > > > grating. With a diffraction grating, light of a particular > wavelength > > > is scattered and shows constructive interference at an angle that > is a > > > function of the ratio of the light's wavelength and the spacing of > the > > > etching in the grating. Nothing else -- no c's, no frequencies, no > > > other buried physics -- just the ratio of the light's wavelength to > the > > > spacing of the etching the grating, a ratio of two distances. > > > > > > If what you say were true, that the wavelength stayed the same but > the > > > speed and frequency changed, then a blue line shifted to green by > the > > > Doppler effect would emerge from the grating at exactly the same > angle > > > as the unshifted blue line. Why? Because, if what you say were > true, > > > the wavelength would be the same and the spacing of the etching > would > > > be the same, so the ratio of those two distances would be the same. > > > > > > This is demonstrably NOT the case. In spectrometers, we have > > > verification that the angle for a blue line shifted to green (and > seen > > > to be green by taking a color film plate) falls exactly where an > > > unshifted *green* line should fall, not where the unshifted blue > line > > > should fall. Thus, we have measurement of both frequency and > > > wavelength, showing that both are shifted. The product of the > > > wavelength and frequency, even for the shifted lines, is > (miraculously) > > > c. > > > > > > There are no holes, no hidden assumptions, Jim. What you propose is > > > flat-out ruled out experimentally. It does not hold water. > > > > What does the change of angle indicate? That VELOCITY has altered! > > No, you did not understand what I wrote. Please reread it. The change > of angle indicates that the *wavelength* has changed. Only the > wavelength and the distance between the etched markings contribute to > the diffraction angle -- NOTHING ELSE. The relationship is [ sin(theta) > = m (lambda)/d ], which is obtained from a geometrical sketch (ninth > grade geometry, note). Here, theta is the diffraction angle, m is the > order index of the diffracted line (there is more than one diffracted > line), lambda is the wavelength, and d is the distance between the > etched lines in the grating. There is no velocity assumed or required > in this derivation at all, let alone a change in one. No. But there should be! You have a distance between the lines, but NO reference as to how long it took the wave fronts (sic photons) to travel the changed distances. As this change is something like 10-^30 sec, put away your watch. Thus a change in > angle indicates *unambiguously* that the *wavelength* has changed. No. Same wrong assumption that the point of intereference is due to changed (magically) wavelength, and not the slightly differing photon velocities. If we threw a handfull of gravel each on a collision course, they would interefere at a point. Now I throw mine faster, and although ALL the gravel still has the same separation (wavelength), the interference occurs at a different position. > Furthermore, the frequency of that light can be determined > independently to assure oneself that it is indeed green and not blue; > this is done by using a detector that is *frequency*-sensitive, unlike > the grating which is wavelength-sensitive. Thus, both frequency and > wavelength are independently measured. Since speed = wavelength x > frequency, it is then straightforward to check whether the velocity is > altered or not. In other words, we do not have the liberty to interpret > a change of angle as a change in velocity, because we have an > independent way of verifying the velocity experimentally. Unfortunately > for you, the product of the independently measured wavelength and > frequency of the diffracted light is c, not c+v. Certain crystals emmit light of a fixed frequency. What is the chemical reaction within the crystal, which causes it to alter its emmitted wavelength, according as to how it is observed??? Hint: the wavelength emmitted by the crystal does NOT alter from its point of view; the Doppler shift noted by the observer is due to the change in VELOCITY. > > > The > > beam on the altered direction intereferes at a different DISTANCE. > > Once again, you have the inbuilt assumption that c=c+v. How did the > > shift from blue to green occur? > > There are two ways in principle this could occur. One is, as you say, > the speed of the wave changes, which (if the wavelength stays the same) > requires a change in frequency. The other ways is if the speed remains > the same, but the frequency and wavelength change. The way to determine > which of these two possibilities has occured is experimentally, as I > outlined using the diffraction grating, which is a wavelength-sensitive > instrument. I think it ignores (the very small) time > > > You ASSUME that it was ONLY the wavelength which altered, when it was > > more probably the velocity of the sine peaks. > > I assume nothing. I measure both the wavelength (with the grating) and > the frequency (with the film) independently, and I use that to > calculate the speed. The only assumption I make is that speed = > wavelength x frequency. Now, do you want to challenge that last > assumption? Absolutely I agree that speed=frequency x wavelength; what I absolutely disagree, is that the "speed" is always the same. > > > I say "probably" > > advisedly, as my bar magnet format for emr particles allows for > > photons of differring velocities to appear identical if their spins > > are correspondingly altered, and conversely. > > > > The camera DID NOT measure the photon velocity; all it did was to > > record per a chemical composition alteration that sine waves were > > impinging at a certain rate on the film. > > You are right in the last paragraph. The camera does not measure photon > velocity. It measures the frequency (because the color film layers > respond chemically to different frequency bands). The diffraction > grating measures the wavelength. I have independent measurements of > wavelength and frequency, with which I can determine three things: > - the wavelength is indeed shifted (measured); > - the frequency is indeed shifted (measured); > - the product of the wavelength and the frequency, which I expect to be > the speed of the traveling wave, is not shifted. > > I'm really sorry to dispel the notion that you had the freedom to > interpret Doppler shift as a change in velocity, not wavelength, and > that you could base a new model assuming a different choice under that > freedom. The fact is, that freedom does not exist. Period. Well I'll take my crystal, which we KNOW, and by definition, emmits a signal of known fixed frequency / wavelength in the lab, and YOU explain how it does NOT exhibit that colour on the film, when I bring the film and crystal beam together. No magic; film which we trust, and a crystal also Jim G c'=c+v
From: Jim Greenfield on 7 Apr 2005 02:15 H@..(Henri Wilson) wrote in message news:<cpj851p3pac413imtr6ulm5nknq7siho09(a)4ax.com>... > On 6 Apr 2005 07:41:52 -0700, "PD" <pdraper(a)yahoo.com> wrote: > > > > >kenseto wrote: > >> "PD" <pdraper(a)yahoo.com> wrote in message > >> news:1112731023.977565.318940(a)z14g2000cwz.googlegroups.com... > >> > > >> > Jim Greenfield wrote: > > >> Absolute Motion" > >> http://www.erinet.com/kenseto/book.html > > > >Uh-huh. And the observed fringe pattern that occurs with sound waves or > >water waves in a ripple tank, also using a diffraction grating, is also > >not due to constructive interference, but is due to the absolution > >motion of the grating with respect to the sound or water waves? > > > >So light's wave behavior and observed wavelike phenomona, stem from > >completely different origins than what is seen in other wave phenomena? > >Is that really what you want to maintain? > > Why shouldn't he? > > The classical wave theory of light breaks down in other respects. > It is obviously inadequate. > Light cannot be treated like water waves or sound. Yes! Pressure waves through air, or ripples on a pond, have Jack S* to do with light (photon travel) through a vacuum. The analogies do not stack. Jim G c'=c+v
From: Henri Wilson on 7 Apr 2005 06:07
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... >>>It should demonstrate that a change of angle >>>as illustrated in the case of the elliptical >>>motion has no effect on the brightness as long >>>as the path length of both beams remains the >>>same while path length does have an effect even >>>if the angle remains constant. >> >> In the elliptical case, the intensity of the beam will remain constant >> only in >> a plane perpendicular to the beam direction. > >Note I am describing the intensity only at a >single point. In other situations that may >extend to other points by symmetry but not >in this case. Yes, the intensity on a 'line' will be constant...but the fact that one beam is coming in at a different angle as you move the mirror around the ellipse will surely affect the way the two beams interfere. It isn't just a matter of intensity. > >> In your example, a cosine >> correction needs to be applied to compare intensities AT ANY POINT on the >> target. >> I'm not sure if tat is relevant. It might only affect the contrast of the >> fringes. > >What is significant is that it shows that >the angle at which the light arrives at >point D is unimportant, hence any possible >angle change in the Sagnac case is also >unimportant, except insofar as it might >lead to a path length change. I wouldn't agree. The angle between the two beams is moreimportant than the intensity. > >>>You said "In my sagnac model, there is both >>>sideways displacement AND angular change." but, >>>if you agree, you should now understand that a >>>change of angle cannot cause any effect at the >>>detector. >>> >> But there is also a path length difference. > >RThat's the key and here I agree with you, but >my point is that the effect must come from >the length change only, not the angle change, >hence that makes it a lot easier to calculate. Well, until we have a better idea of what a photon really is, I cannot say I would agree on that either. > >> 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. > >>>>>I'm sure we are close to a mutual understanding. >>>> >>>> Not all that close yet. >>> >>>Shame. OK, what argument can you offer that >>>my gedankens are wrong if you disagree? >> >> What I just stated above. There is both a path difference and an angular >> change. > >Yes but my point was that only the path length >change creates a brightness change at point D, >I wasn't saying anything about Sagnac yet. If >you agre the points above, then we can move on >to use them in the analysis. > >>>http://www.javatester.org/version.html >>> >>>It also gives links for getting the Sun >>>version such as this: >>> >>>http://www.java.com/en/download/ >> >> Their web page is as hard to understand as their program. > >Yes, the JavaTester page makes that point. >All I did was click the java.com link then >click the "Begin Download" button and accept >all the defaults and it worked. I have version 1.1.4 > >>>I just followed the defaults and it >>>worked fine. >>> >>>>>If it works, switch on one beam at a time >>>>>using the check boxes and move the location >>>>>of the detector using the slider. Wiggle it >>>>>about and see if you agree with the beam >>>>>paths. Then switch both on and look at the >>>>>angle between the beams at the detector. Let >>>>>me know what you think. >>>> >>>> Have another attempt. >>> >>>The program seems OK having tested from >>>another site. If you install the JVM from >>>Sun, it should solve the problem. >> >> My Java was not enabled but your applet still wont appear. > >Odd, the JavaTester site may help > >http://www.javatester.org/version.html > >>>> I gave up on Java. There has to be an easier way. >>>> >>>> Visual basic is SO simple. >>> >>>It is, but you have to pay for it :-( >> >> True >> >>> >>>The Java SDK is free :-) >> >> But the free version is very difficult to use. > >True, I found the display elements tedious >but Swing helps and the EJS program does all >that for you. Anyway, let's get the simulation >running so we can address the Sagnac case, the >software is only a means to that end. I'll run one up on Vbasic too. > >> Java code itself is pretty easy. >> Getting the thing to run is the hard part >> >> My daughter who is a programer is currectly learning Java. She agrees it >> is >> very confusing and hard to use. > >Maybe she can see why your JVM isn't working. >I had installed ages ago on my home machine >but the install I did today was straight from >the site on a bog-standard IE6 machine. After three months, she is still pretty mystified by it. > >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. |