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Hi
Ive tried posting this to the original thread but it doesnt seem to post so hopefully this gets through ... I would like to take the opportunity to show how a recent published paper has confirmed earlier predictions of mine, made here on sci astro and astro-research newsgroups and at my website since 2001 at www.gammarayburst.com . Theoretical predictions based on my theory predict that grb lightcurves have numerous rebrightenings and that this must be visible in the observed data. I then explained at numerous times and at my website how these flucuations could be seen in the observed availble grb data. The new paper (some quotes from author K Stanek later here in this post) also confirm how wrong my critics were to suggest that my predictions of these rebrightenings were unverifiable and unscientific. Staneks paper also shows how wrong they were to suggest that my use of incorporating the fluctuations in observed lightcurves was unscientific. In fact Stanek shows that my method, outlined by me in quotes going back here to 2001 is the only correct one. Stanek has has not only confirmed my predictions, but has supplied firm evidence that supports my theoretical model of a variable c in a non big bang universe. Indeed his paper also admits that current beamed theory cannot explain these observations. Please note since 2000 and before I have not only been able to explain all observations made till then but alsoI predicted into the future till now, including those now "discoverd for the first time " in Staneks paper. Without realizing it Stanek has just supplied the first verifiable evidence that the speed of light is not constant for the observor. (Stanek et al; astro-ph/0602495 2006) Note from my quotes that I have stated that rapid variations in the optical lightcurve should be seen if the time scale of the sampling were short enough. One of my theoretical criticisms of current procedures and beamed theory was that the power law fitting of optical data employed by the astrophysics community was in fact a misguided procedure that disguises the true variability of magnitude within the optical lightcurves by incorrectly smoothing out the observed variability in the the optical lightcurve, particularly in early time lightcurves where flucuationsare more easily seen due to the relative brightness of grb afterglow. I have supplied illustrated graph samples at my website www.gammarayburst.com since 2000 of how if one takes into account the observed variability in the lighthcurve data one can extrapolate numerous, rapid and pronounced variabilty in brightness of the grb afterglow as it decays. As you can see, my critics not only said that my theory was wrong and proof of this was that their evidence (power law chi squared smoothed decays ) showed that there were no fluctuations as predicted by their beamed theory. They alsotried to suggest that my attempts to argue that one shouldnt apply power law smoothing was unscientific. As you can see if you look at Staneks quotes, in fact now the only acceptable way to analyse grb optical decay is by using the very methods I proposed back in 2001 and not the misguided method of power laws as championed by my narrow minded sceptics since 2001. Here are samples of my quotes below. In addition my quotes below implicitly predict that X ray lightcurves will also exhibit dramatic rebrightenings and at later times than expected under beamed theory allows. This prediction is also rubbished as impossible and unverifiable by one critic below. Yet as we know now from several recent Swift bursts (outlined in Staneks paper) that this is not only possible but most likely the norm My first quotes below are from my 1st post from the thread `Swift grb satelitte` started on nov16 2004 the url is below, unwrapped ... http://groups-beta.google.com/groups... g.google.com Sean Nov 16 2004... " the shorter the time frame of the exposure of the CCD the more detail will emerge..... more `peaks` will emerge in shorter ccd exposure times for SWIFT. This will give the appearance of more numerous rapid rebrightenings than current *theory allows*.." "...SWIFT will also see these rebrightenings always occuring at later times in longer wavelengths. Ie/ a rebrightening observed in UV will appear to peak slightly later in optical. If SWIFT observes a burst with enough detail in its Gamma X UV OT filter bands it should be possible to chart features that first occur in gamma then appearing seconds later in X..." ".. This will be a progression directly proportional to wavelength so that if it takes 10 seconds for the `spike` to move from 1nm to 10nm then it will take 100 seconds to move from 10nm to 100nm... " And here are some quotes from Stanek which show that new analyses of data can only confirm my predictions made here in sci.astro 2001 and 2004. Please note that the opinions of my critics are now confirmed, as I always suspected,.. as being dogmatic , incorrect and unscientific. Stanek et al; astro-ph/0602495 2006.... ...."the large number of anomalous optical afterglows can no longer be seen as a small wrinkle on the standard afterglow model. In fact, unless there is sufficient data to suggest otherwise, it would be only prudent to assume that any given afterglow might be anomalous. As a result, some of the often employed procedures, such as deriving the jet opening angle using a broken power-law fit to the optical light curve, in many cases might have a poor statistical significance and be simply not applicable..." ...."rapid variations often seen in Swift-XRT data would also be seen in the optical light curves, given good enough sampling. As a result, some of the often employed procedures, such as deriving the jet opening angle using a broken power-law fit to the optical light curves, in many cases might have a poor statistical significance." "..Given the unusual behavior observed in the optical wavelengths for these two bursts, it is useful to investigate their X-ray light curves as well. Indeed, X-ray afterglows observed by Swift-XRT have been shown to have features (Nousek et al. 2006) not expected in the standard afterglow models, including giant ares such as observed in GRB 050502B (Falcone et al. 2006). The origin of the ares is still under investigation (e.g. Zhang et al. 2005)..." "..the overall behavior between the two bands is similar, but with clear short-timescale variations, as reported before by Morris et al. (2006b). Trying to describe these erratic events with smoothpower-law fits is often a dubious statistical proposition..." As you can see from Staneks paper on all 3 points my critics are proved wrong and my predictions, made before Swift was even online, are not just confirmed as possible but are the norm for grb phenomena. Finally, here are samples of what can only be confirmed now as `unscientific` critisms made on newsgroups from members of the self styled `scientific` community. It makes one wonder how they got their jobs. Craig Markwardts post of mar 28 2005 of the same thread as my quotes... "...Scientifically speaking, if you were claiming a "good fit," then you would be giving proportionality parameters, confidence limits on those parameters, and goodness-of-fit measures (i.e. chi-square statistics). I note that you continue to ignore such formal measures and instead speculate wildly...." ... and here Craig tries to push the theoretical approach of power law smoothing as being correct over my prediction that in fact there is significant small scale variabilty in optical lightcurves that has been erased by `smoothing`... (Craig Markwardt april 11 2005)".. And the point is that right now you are using a trial-and-error approach which: (a) ignores many possible combinations of valid parameters which may not be so flattering to you; (b) ignores uncertainties on measurements; and (c) ignores possible systematic biases. " Craig Markwardt feb 22 2005 sci.astro.. " In fact, if you had read some of the literature, you would have found measured hard-to-soft gamma-ray lags to be significantly less than 0.1 seconds. (Norris 2000). But it appears that you have not even tried to consult the literature. When you get your wavelength values right, you will see that you would predict significant lags down to 0.5 keV or to optical... " As you can see above, Craig stands by his claim that my predictions of time lags between hard and soft high energy observations of than 0.1 seconds are incorrect and not possible. As seperate 060218 data shows he is completely wrong and the data verifies my predictions that some grbs will have significantly longer delays between all wavelengths (including in X)than believed possible by current beamed theory. Below are a few more quotes from M Hardcastle, J Lazio and C Markwardt from an even earlier thread ... ....`beamed gamma ray bursts`Sat, Oct 27 2001 9:09 am... They try here to argue that my criticisms of using power law smoothing is unscientific and unverifiable Looks like they were wrong and I was right, as it turns out, as Stanek can now show, that using power law smoothing with all its parameters and chi squaring is at best innapropriate. His recommendation is to incorporate the detailed rebrightenings previously smoothed out by power law, just as I recommended. Please read the following quotes or go to the full thread in sci.astro oct 2001. I`ve interspersed quotes from my posts from 2001 followed with the relevent responses from eminent non scientists CM MH and JL Sean... I believe in fact that if observations in the optical spectrum, of the afterglow were to be made in numerous very short lets say 10 sec exposures(is that possible )every 10 secs over the first day or so from the gamma burst trigger We would see in the optical spectrum a very erratic multi peaked profile in a graph of energy flux /time that should mimic very closely the gamma ray energy / time profile One could just as legitimately choose other extremes within error margins and interpret grb 970508 optical lightcurve as having at least 6 peak flashes between 1/2 to 1 1/2 mag. If 990123 is debateable depending on error margin interpretation, Grb 970508 is definitive proof that both beamed theory and the use of power law smoothing is incorrect and misguided. These peak flashes I refer to can be seen at approx. 0.2, 0.3, 1.05, 1.1, 1.2, 1.5, 2, 2.8, 3.5 and 5.5 days post trigger(Pian etal: astro-ph/9710334) all within the accepted error margins supplied. Martin Hardcastle... Sorry, I don't see any statistically significant peaks at these positions, with the possible exception of the one at 0.2 days. So this is not `definitive proof' of anything. The data are consistent with a power-law model within the errors in the region where the authors fit one, or so it seems to me. It's easy to check; get hold of the raw data and some fitting software and see what the reduced chi^2 is for the straight-line fit in this region. Of course, this doesn't mean that you're wrong that the peaks *are* there; but you have to show that they are significant. What's the change in reduced chi^2 when you add models of these peaks to the overall power-law decline? (Here I give Martin credit for at least leaving the door open to the possibility that maybe occasionaly there might be a lightcurve with some fluctuation.) However if he expects me to try to show this by then applying power law smoothing to the data then thats counter productive as its exactly this use of power law which I object to in the first place. Its like trying to show that GR doesnt explain gravitational lensing by using GR to see if it can... And Martins next point only highlites the fact that if I were to try to show that fluctuations do exist I probably wouldnt find any if I did have to do it his way with power laws..Sean) Martin... Anyway, consider fitting a straight line to the data points between 0.1 and 0.5 days. What is the reduced chi^2? I think you'll find that almost any model of these data is an acceptable fit, because the error bars are so large. An understanding of experimental error is absolutely key to analysing this sort of data. I looked quickly at your plot at your web site but it's missing the error bars, which means it's impossible to say how real any of the structure is that you describe. Sean.... Following on from that is it not true that power law chooses `suitable points `in error margin to give a straight line power law? and J Lazio`s reply... Not in the way you seem to be describing it. A *fit* is an attempt to find a simple function that describes a large number of data. One could have an adequate fit even though the fit misses some of the data by more than dm. If one wants to describe the fit accurately, one also has to quote a "goodness of fit." This is typically done using a chi-squared statistic that describes how good the fit is and how probable it is that a comparable fit could be achieved from random data. Sean... If one were to draw a profile through the mid point of each observation one would get a erratic multi- peaked structure , Not a straight line power law. And the irregular profile would be the more `correct ` way to represent the data. Would it not? J Lazio.... Not really. First off, the entire purpose of estimating error bars is to illustrate how well measured a quantity is. We never actually know what the "true" value of the magnitude is, but we think it is probably "close" to m, "close" within about dm. Second, one can always find a function, using N parameters, to fit N data. That's not meaningful, though. The idea behind physics (and astronomy) is to find simple expressions that describe experiments and observations. If you fit all N data with an N parameter function, then as soon as you obtain a new datum, you need a new function. If you fit N data with a 2 parameter function *and* it is a good function, then you can also describe N+1 data with the same function. (And finally Craig Markwardt replies with an argument that we now now to be misguided at best below about how the only way to analyse grb optical lightcurve decays is to dogmatically adhere to chi squaring and power law smoothing of the data to make sure it fits a decidedly useless beamed theory. Below Markwardt insinuates my approach of including the fluctuations in the observed lightcurve is dubious! Do you still think so now Craig? ) C Markwardt... Also, as has been pointed out, trying to infer that something is a "peak" when the data are as noisy and as sparse as they are, is in my view a dubious practice. Simply "connecting the dots" will lead to *a possible* solution, but ultimately a very *low probability* one a priori. A more appropriate approach would be to start with a featureless model of the decline (say, a power law), then add a gaussian or some other simple parameterization of the putative peak. By computing the F-statistic, one can then find out how significant the additional peak is, statistically speaking, compared to the overall decline. If it's significant at the 95% level, then it may be worth considering further..." ! (yeah right Craig..maybe you should take a look at Staneks paper.)` Sean |
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