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On 15 Mar 2007 19:17:29 -0700, "Jerry" wrote:
On Mar 15, 6:00 pm, HW@....(Henri Wilson) wrote: ALL THE VELOCITY CURVES EVER PRODUCED USING SPECTRAL DOPPLER SHIFTS ARE PROBABLY VERY WRONG. That's your way of hiding from the fact that your program fails to produce the correct velocity curves. Utterly pathetic. You will never make it in medicine with your negative attitude problem.... Jerry "When a true genius appears in the world, you may know him by this sign, that the dunces are all in confederacy against him." --Jonathan Swift. |
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On Mar 15, 5:32 pm, HW@....(Henri Wilson) wrote:
I also had to adjust both the comparative brightness and orbit speed of the 'outer star'. Both values are about 0.4 of the inner star. ...which provides an indication of the relative masses. I achieved an even closer match when I included a third object wirth a 90 degree phase shift. YOU CAN'T DO THAT!!! There is no way that adding the third object where you do could result in a stable orbital configuration. In every paper I have read about cepheids the authors state straight out that they have no model that can explain the brightness variations . You are obviously not up on the latest research. With recent advances in supercomputer capabilities, it has been possible for astrophysicists to include in their models effects that previously had to be ignored, because modeling those effects required computational power far exceeding that which had been available. The state of the art in Cepheid modeling as of early 2005 is described in the following link: http://www.lesia.obspm.fr/astro/cepheids/program.html In the last couple of years, I've seen even better results! Jerry |
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On 16 Mar, 02:33, HW@....(Henri Wilson) wrote:
On Fri, 16 Mar 2007 00:18:00 -0000, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message .. . On 15 Mar 2007 01:26:03 -0700, "George Dishman" Nope, that would be of no use at all. Consider a simple circular orbit of the pulsar P around the barycentre B as seen by an observer O very far away (not to scale): B P x P' O | | |- D -| Light from the two locations P and P' would be launched with the same speed towards the observer, c' = c+0.7v, because I've drawn them at 45 degrees to the LoS. The light from P would be expected to take D/c' longer to reach us. That's a strange drawing George. The barycentre should be where x is. Anyway I know what you mean. I don't think you do. Let me add the location of the companion dwarf as C and draw the two situations separately. Here's the first: C B P O The companion is lighter so it's farther from B. Here is the second situation quarter of an orbit later: C B P O Of course the observer sholud be farr off to the right of your screen Oh all right. I thought you were trying to draw something else. Same result anyway. .... Point x is midway between P and P' where the light path is perpendicular to line x-B. In ballistic theory the gravity of the star accelerates the light between P and x and then slows it between x and P' so that the speed at P' is the same as light emitted at P'. Everything from there to O is the same. The time it takes the light to get from P to P' is therefore slightly _less_ than D/c' because the mean speed is slightly higher than c'. The Shapiro effect is the difference between that time and D/c'. Yes I'm aware of this. The average speed is faster than c' between P and P'. Right so the signal arrives earlier, it is not a delay. The gravitational redshift is identical in each case as is the eventual speed. that's right. OK, now we have cleared that up, if you plot the alteration of arrival time as a function of the phase, you will find it peaks when the source is behins the companion and the relative width of the peak depends on the inclination of the orbit. There will be no effect for face on and a high narrow peak for nearly edge on. However, there will be almost no velocity effect since any increase between P and x is always matched by a corresponding decrease between x and P'. That's why we can use it as a reference for the phase. Consider a pulsar in an edge-on circular orbit. Pulses from the near and far sections of the orbit move towards you at c and that from the edges at c+v and c-v. Bunching of pulses is a maximum at maximum acceleration, ie., for pulses emitted from the far section of the orbit. It is minimum for those emitted at the near, or 'convex' section. There is also the effect that consecutive pulses from the edge travel slightly differnt distances to reach us. Those from the edge where the source is approaching us travel progressively shorter distances so are slightly bunched by the velocity while those on th other side travel a little longer each time so are moved apart. However, the 'bunched section' moves towards the observer at a slower speed than does the group of pulses from the edges. Slower than those from one edge, faster than from the other. Now, my original method does not take this into account, although the red velocity curve it generates actually shows the arrival velocities. The velocities affect the 'y' position but the changed time of arrival affects the 'x' position. However, any change in that from one pulse to the next also affects the _relative_ separation hence looks like a modification to the velocity. I cannot yet see how your 'pulses separation' method does NOT include the VDoppler. It SHOULD include it but if as you say above your program does not take this into account, that could explain why it is missing the VDoppler effect. I'm working on it. I'll eventually find what's happening. .... It will be done....but it isn't as simple as one would think. I can see that your approach might make it tricky. Let me know when you crack it. George |
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On 15 Mar 2007 19:43:54 -0700, "Jerry" wrote:
On Mar 15, 5:32 pm, HW@....(Henri Wilson) wrote: I also had to adjust both the comparative brightness and orbit speed of the 'outer star'. Both values are about 0.4 of the inner star. ...which provides an indication of the relative masses. I achieved an even closer match when I included a third object wirth a 90 degree phase shift. YOU CAN'T DO THAT!!! There is no way that adding the third object where you do could result in a stable orbital configuration. In every paper I have read about cepheids the authors state straight out that they have no model that can explain the brightness variations . You are obviously not up on the latest research. With recent advances in supercomputer capabilities, it has been possible for astrophysicists to include in their models effects that previously had to be ignored, because modeling those effects required computational power far exceeding that which had been available. The state of the art in Cepheid modeling as of early 2005 is described in the following link: http://www.lesia.obspm.fr/astro/cepheids/program.html In the last couple of years, I've seen even better results! See http://www.users.bigpond.com/hewn/bunching.jpg .....then burn all yer books... Jerry "When a true genius appears in the world, you may know him by this sign, that the dunces are all in confederacy against him." --Jonathan Swift. |
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On 16 Mar 2007 00:53:29 -0700, "George Dishman"
wrote: On 16 Mar, 02:33, HW@....(Henri Wilson) wrote: On Fri, 16 Mar 2007 00:18:00 -0000, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message .. . It SHOULD include it but if as you say above your program does not take this into account, that could explain why it is missing the VDoppler effect. I'm working on it. I'll eventually find what's happening. ... It will be done....but it isn't as simple as one would think. I can see that your approach might make it tricky. Let me know when you crack it. George See http://www.users.bigpond.com/hewn/bunching.jpg This shows how the phase of the TRUE velocity maximum changes with distance when compared with the maximum bunching. The latter (maximum pulse arrival rate) is wrongly assumed to indicate the maximum doppler shift. I think this answers your questions George. The standard doppler approach applied to pulse arrival rate gives a completely wrong answer. "When a true genius appears in the world, you may know him by this sign, that the dunces are all in confederacy against him." --Jonathan Swift. |
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On Mar 16, 3:23 am, HW@....(Henri Wilson) wrote:
On 15 Mar 2007 19:43:54 -0700, "Jerry" wrote: You are obviously not up on the latest research. With recent advances in supercomputer capabilities, it has been possible for astrophysicists to include in their models effects that previously had to be ignored, because modeling those effects required computational power far exceeding that which had been available. The state of the art in Cepheid modeling as of early 2005 is described in the following link: http://www.lesia.obspm.fr/astro/cepheids/program.html In the last couple of years, I've seen even better results! Seehttp://www.users.bigpond.com/hewn/bunching.jpg ....then burn all yer books... All you have in the above link is a bunch of cartoons. Show me that you can simultaneously match the luminosity and radial velocity curves of RT Aurigae. Thus far, you have done nothing but emit a lot of hot air. Your version of huff-puff, I suppose. Jerry |
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![]() "Jerry" wrote in message ups.com... On Mar 16, 3:23 am, HW@....(Henri Wilson) wrote: On 15 Mar 2007 19:43:54 -0700, "Jerry" wrote: You are obviously not up on the latest research. With recent advances in supercomputer capabilities, it has been possible for astrophysicists to include in their models effects that previously had to be ignored, because modeling those effects required computational power far exceeding that which had been available. The state of the art in Cepheid modeling as of early 2005 is described in the following link: http://www.lesia.obspm.fr/astro/cepheids/program.html In the last couple of years, I've seen even better results! Seehttp://www.users.bigpond.com/hewn/bunching.jpg ....then burn all yer books... All you have in the above link is a bunch of cartoons. Show me that you can simultaneously match the luminosity and radial velocity curves of RT Aurigae. Thus far, you have done nothing but emit a lot of hot air. HAHAHA! Pot. Kettle. Black. |
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On 16 Mar, 09:32, HW@....(Henri Wilson) wrote:
On 16 Mar 2007 00:53:29 -0700, "George Dishman" wrote: On 16 Mar, 02:33, HW@....(Henri Wilson) wrote: On Fri, 16 Mar 2007 00:18:00 -0000, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message .. . It SHOULD include it but if as you say above your program does not take this into account, that could explain why it is missing the VDoppler effect. I'm working on it. I'll eventually find what's happening. ... It will be done....but it isn't as simple as one would think. I can see that your approach might make it tricky. Let me know when you crack it. See http://www.users.bigpond.com/hewn/bunching.jpg This shows how the phase of the TRUE velocity maximum changes with distance when compared with the maximum bunching. The latter (maximum pulse arrival rate) is wrongly assumed to indicate the maximum doppler shift. It is hard to tell but it looks as though the pulses in the top line are regularly spaced. If so it is wrong, they should be bunched closest at the 90 degree mark because each one travels less distance to the observer than the previous pulse (speed is constant at c+v) and most widely spaced at the 270 degree mark where each travels farther (at c-v). The bottom line looks right in that the acceleration dominates and the maximum is at the 0 degree mark (which is also where the Shapiro delay peaks). I think this answers your questions George. No, my first question was to find the row where the combination of the velocity and acceleration effects gives a maximum bunching at 45 degrees and you haven't shown that line. Specifically though you need that incorporated into your program so that we can find the distance at which the measured phase shift occurs and you may then want to also consider elliptical orbits which will change both velocity and acceleration versus phase and yaw due to Kepler's laws. The diagram has been helpful as it shows you are still not taking the velocity effect into account and hopefully will give you a steer on how to do that, but it is only a step to fixing the error in your program. Once you do that, you need to be able to say what extinction distance produces a phase shift of the order of 10^-5 degrees so you need to be able to get numbers out of it, but we can estimate it from the 45 degree figure with a bit of simple trig. George |
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![]() "Henri Wilson" HW@.... wrote in message ... On Fri, 16 Mar 2007 00:22:44 -0000, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message news ![]() On Wed, 14 Mar 2007 23:47:58 -0000, "George Dishman" wrote: I also had to adjust both the comparative brightness and orbit speed of the 'outer star'. Both values are about 0.4 of the inner star. ...which provides an indication of the relative masses. I achieved an even closer match when I included a third object wirth a 90 degree phase shift. You can't do that, it's an unstable configuration. You could get away with one at a Lagrange point but there is a limit on the mass ratios. I wasn't suggesting that an object was in orbit 90 out. As far as we know that is indeed impossible. Fine, so you are not allowed to put one into your simulation and claim you have succeeded. In fact you told me you got the motion of the stars by simulating Newtonian gravity so your configuration should have been unstable. It looks as though that part is buggy too. ...but there could be other reasons...tidal effects(?) Then simulate tidal effects. All you can do for now is use two stars and get the best fit. If the residuals are within the observational uncertainty you have a match and if not you don't. The fact that it was 90 and not 80 or 100 made me wonder. Pointless since it cannot exist. I was wondering about the material that is falling into the neutron star. If it is spinning, its speed would drop of with distance. If it wasn't spinning the pulsar would be slowing down. So look up the rate of change of the pulsar frequency, it is one of the key published values. Of course, you can create any possible shape with sufficient harmonics but Keplerian orbits produce limits, that is the anture of the test. You can't just add more factors. Everything I add is strictly in accordance with the BaTh. I cannot simply add any old curve to produce the one I want. There are strict limitations particularly for elliptical orbits. Yes, and a third object is not allowed ! ![]() Of course it is....many star curves clearly involve a third or more object. Then those curves will almost certainly be failures too, you cannot have a stable configuration with a third object except under _very_ limited conditions (e.g. figure of eight or the very disparate separations like the Sirius system). I don't think you have fully realised the complexity of this whole issue George. I don't think you realise the constraints Keplerian orbits place on you Henry. George |
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On 16 Mar 2007 03:19:00 -0700, "George Dishman"
wrote: On 16 Mar, 09:32, HW@....(Henri Wilson) wrote: On 16 Mar 2007 00:53:29 -0700, "George Dishman" wrote: On 16 Mar, 02:33, HW@....(Henri Wilson) wrote: On Fri, 16 Mar 2007 00:18:00 -0000, "George Dishman" wrote: "Henri Wilson" HW@.... wrote in message .. . It SHOULD include it but if as you say above your program does not take this into account, that could explain why it is missing the VDoppler effect. I'm working on it. I'll eventually find what's happening. ... It will be done....but it isn't as simple as one would think. I can see that your approach might make it tricky. Let me know when you crack it. See http://www.users.bigpond.com/hewn/bunching.jpg This shows how the phase of the TRUE velocity maximum changes with distance when compared with the maximum bunching. The latter (maximum pulse arrival rate) is wrongly assumed to indicate the maximum doppler shift. It is hard to tell but it looks as though the pulses in the top line are regularly spaced. That line is the layout immediately after emission (one orbit) All the pulses are (almost) equally spaced. If so it is wrong, they should be bunched closest at the 90 degree mark because each one travels less distance to the observer than the previous pulse (speed is constant at c+v) and most widely spaced at the 270 degree mark where each travels farther (at c-v). George, each line represents a distance further from the source. The diagram is not wrong. The maximum bunching occurs at the 0/360 mark. (furthest from observer). Widest spacing is at the 180 mark. That's how ADoppler works. The bottom line looks right in that the acceleration dominates and the maximum is at the 0 degree mark (which is also where the Shapiro delay peaks). All the lines are correct. They show the layout at different distances, increasing down the screen.. The program merely shows how each pulse moves after emission, given that its velocity is c+vsin(x/T). I think this answers your questions George. No, my first question was to find the row where the combination of the velocity and acceleration effects gives a maximum bunching at 45 degrees and you haven't shown that line. The acceleration term dominates from the start. The source velocity is so small that the pulses are virtually evenly spaced after one orbit. Do you see that? That is represented by the top line....with the first pulses at the RHS. As distance increases, the pulses emitted at the 90 mark move towards the leading ones, causing bunching there. Specifically though you need that incorporated into your program so that we can find the distance at which the measured phase shift occurs and you may then want to also consider elliptical orbits which will change both velocity and acceleration versus phase and yaw due to Kepler's laws. The diagram has been helpful as it shows you are still not taking the velocity effect into account and hopefully will give you a steer on how to do that, but it is only a step to fixing the error in your program. George you are totally confused. The diagram is correct. Astronomers unwittingly use the pulse arrival rate as a measure of doppler shift. They believe the higher the arrival rate, the faster the radial velocity towards Earth. As you can see, this is is completely wrong, both in magnitude and phase wrt the brightness curve. The true maximum radial velocity occurs at the 90 degree mark. Once you do that, you need to be able to say what extinction distance produces a phase shift of the order of 10^-5 degrees so you need to be able to get numbers out of it, but we can estimate it from the 45 degree figure with a bit of simple trig. George you don't seem to understand. I suggest you write your own program. It is quite simple really...for circular orbits. Set up an array of speeds around the orbit: For K=0 to 360 lightspeed(K) = 2000 * (Sin(pi/180 * K) * vone) next (the starting point is as shown in my diagram.) then: using a timer, repeat the loop: For j = 0 To 90 (gives 90 pulse) If j = 22 Or j = 45 Or j = 67 Then n = 0 Else n = 255 (red line showing 90,180, 270 points) Line ((140 * j) + (sec * lightspeed(360 - (4 * j))), 2000)-((140 * j) + (sec * lightspeed(360 - (4 * j))), 2200), RGB(255, n, 0) Next sec= sec+1 George "When a true genius appears in the world, you may know him by this sign, that the dunces are all in confederacy against him." --Jonathan Swift. |
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