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Unfortunately it does seem that today's science is one of discarding any anomalous results unless they are so prevalent that you have to address them. I was even taught to do this while training as a Chemist. If a result didn't agree with the projected answer it was discarded and only those that did agree were kept thus allowing the results to agree with the expected outcome. Any surprise I tend to be skeptical to many of the ways that some scientists do their work?
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Howling from the Shadows It must be fun to lead a life completely unburdened by reality. --- JayUtah You can't reason an irrational person out of an irrational belief. --- Noclevername Apollo: The History and the Hoax Enter the World of Athran |
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You'd think we'd have cold fusion by now...
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Feynman >~~~~< Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool. Religion is a culture of faith; science is a culture of doubt. |
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Jerry, I see you have nine arrows in your quiver there. But for supernova non-experts like me, could you tell us which one of those arrows is most likely to hit the bullseye? If I were to try firing off those arrows they'd likely fly all over the place. Remember what Einstein said: (something like) people opposed to relativity raised countless arguments against it, when just one good argument would have sufficed.
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Phantom Wolf wrote:
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Now, that doesn't mean that you can never discard anomalous data, but there has to be a good and consistent reason for doing so.
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If they can get you asking the wrong questions, they don't have to worry about the answers. |
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I'll just respond to your point 1, which I believe is telling.... Quote:
You make a rational and integral part of the program sound like some conspiracy of data picking. I'm not sure why. Well, with your naysaying agenda, I guess I do see why.
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Everyone is entitled to his own opinion, but not his own facts. |
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Local Hypernova, the brightest of supenova events, have light-curves that lose one magnitude in 20-30 days, the same general length as what are interpreted as being supernova Ia at high redshifts. No high redshift hypernova, with redshifts greater than one and corresponding light curves of 40-60 days have been observed. Why? Because we are mistaking high redshift hypernova for supernova Ia. Edit: This is as concise as I can make it.
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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You should not have to stand up for them. If I do not have the facts straight, it should be easy for them to sic a grad student at me with a better club in his bag than my misspelling of Olber’s name. I have my teeth in this one, and I am not letting go. edit - typo
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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I'm getting your general point, but it seems like a bit of a long shot, at least in the game of changing people's minds. Your critique rests on the two types of supernovae being mistaken for each other. Yet this very confusion will make your task quite difficult. For instance, what are the criteria that we could use to distinguish a very high redshift supernova from a hypernova? More significantly perhaps, the mainstream should be able to trump you by just looking at low redshift supernovae, where it's clear they are SNe and not hypernovae. If they can show time dilation for these SNe, you're beat, aren't you? |
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As we look back in space and time, the further back we look for a certain type of event, the more likely we are to see the brightest and the biggest -if you were looking at our solar system from somewhere out in the galaxy, you would be much more likely to spot Jupiter than the earth. This is known as a “Malmquist bias”. In deep space surveys, this bias is expected to run at about 4%, which means on average, the average size of objects we find increase by 4% every time the distance increases by a factor of a hundred. In theory, a certain type of supernova explosion, type Ia, are thought to be quite uniform, and therefore, we should see little, if any Malmquist bias looking into the past. The light curves we see from these supernova should always be about the same length, losing one magnitude from peak in about 15 days. However, if the universe is expanding, when we look at very distant objects, these light curves should appear to occur more slowly. At a red shift of one, an ‘average’ supernova Ia should appear to lose one magnitude in thirty days instead of 15. In 1939 Wilson predicted that with powerful telescopes we would be able to see this time dilation in very distant supernovae. In the mid 1990’s, observation of redshifted supernovae appeared to prove this is true. In the nine years since Liebengut “confirmed” this, we have learned a lot more about supernovae - (I certainly thought he was right, four years ago.) Specifically, locally, some supernovae that are similar to type Ia take up to 28 days to lose one magnitude, just like the distant events. These have been classified as type Ic hypernovae, and they are brighter and more rare than the local type supernova type Ia. (the plural forms of supernova and hypernova end with “ae”, supernovae and hypernovae) So how do we know whether the light curves Liebundgut observed belong to type Ic hypernovae or type Ia supernovae? This is extremely important because if they were type Ic hypernova Liebundgut observed, the Wilson prediction is false, the universe is not expanding, and there was no big bang. A large number (> 200) supernova Ia type events have now been observed. The evidence is mounting that astrophyscists are overestimating the time dilation in the distant events: When time dilation is factored in, the light-curves appear to be smaller with increasing distance. Since a Malmquist bias would predict just the opposite, we should see slightly larger supernova Ia with slightly longer light-curves, the only reasonable explanation for why the light-curves are getting smaller is that the time dilation factor is too great. However, if time dilation is not factored in, the light-curves are on average too long to be slightly larger supernova type Ia. However, this would not be true if the most distant events are more like the “hypernovae Ic”, rather than supernova Ia. So who is right? The few of us who say they are “hypernova Ic” and bigger supernova Ia, or the many who say they are on the average, smaller supernova Ia? There are compelling reasons to assert we are right: 1) There is no reason on heaven or earth to think that the distant supernova Ia should be smaller than the local sample. They should be, on average larger, and if the attenuation of space is greater than we think it is, we should see even fewer of the normal size supernova than we think we should. This is true: the most recent search for distant supernova yielded less than 5% of the predicted number. However, this is close to the number of hypernova Ic we should expect to find if we have underestimated the attenuation of space. 2) There is very little difference in the spectra of hypernovae Ic and supernova Ia, and this is especially difficult to distinguish at great distance. 3) Since the “hypernova type Ic” are the biggest and the brightest of the local events, they should also be listed in the most distant events we find, and if these “hypernova Ic” are time dilated, they should have light curves that lose one magnitude in fifty to sixty days! We have not found any light curves that look like this. Where are they? A much better answer is that we do see them: They are dimmer than we would predict and show no evidence of time dilation. In fact, just the opposite, they nullify the Wilson hypothesis. The only reason for interpreting the data any other way, is to force the reduced data to be consistent with a big bang scenario. Observations do not work that way. They are real, and they are telling us the theory is wrong.
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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That is the finding that enabled Sne Ia's to be used as standard candles. This is a crucial factor that must be added to the analysis - one you apparently left out (?) Type I's differ from Type II's in that they lack any detectable amounts of hydrogen in their spectra. And there is a vast difference between Type Ia's and Types Ib and Ic. Types Ib and Ic represent variants of the basic core-collapse scenario for massive stars, which result in neutron stars or even black holes after they explode. Type Ia's blow completely to bits, leaving nothing behind. In The Runaway Universe Goldsmith goes on for two pages identifying the additional differences.
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Everyone is entitled to his own opinion, but not his own facts. |
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Filippenko had a nice review of the spectral characteristics of supernova. There are some significant spectral differences between Type Ia and Ic - such as presence or absence of H lines and Si lines among other differences.
Jerry, do the distant supernova claimed to be Ia show the spectral characteristics typical of Ic? |
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As long as this magnitude curve follows the predicted Hubble curve, everyone is happy. But two alarming things are happening: The average light curve widths appear to be getting smaller, meaning distant supernova are on average smaller. BIG red flag - this should not happen. Secondly, even with this correction, the supernova were dimming too fast to stay on the Hubble curve (between a redshift of 0.3 and 0.5.) This is why Permutter concluded the expansion rate is increasing. Quote:
Middleditch has concluded these explosions, which also emit killer vectored gamma rays, are the collision of double binary white dwarfs type stars. If this is true, the hydrogen component can vary from near zero to a hundred, depending upon the atmosphere of each of the four progenitors. This would explain why these events also have many of the elemental signatures of both supernova Ia and Ic. In a sample of about 11 events observe at very high redshift, Tonry concluded 8 were supernova and 3 were either hypernova or undetermined, even though the light curves of all eleven events are about the same length as local hypernova, if time dilation is not factored in. But if time dilation is factored in, All of these high redshift events would have the same sized light curves (actually slightly smaller) as local supernova Ia, and NONE of them have the longer light curves we should expect to see in the time dilated hypernova. Why? A more logical conclusion is they are all more like local hypernova, there is no time dilation, and the attenuation of space is so great we cannot see the type Ia at these distances at all (except for the ones weeded from the sample because the light curves, once corrected for time dilation, are too small.)
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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Jerry, What I'm looking for here is whether or not there is clear spectral evidence that allows Ia to be distinguished from Ic Hypernova. For example, Filippenko says this:
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If so, it would seem to be pretty straight forward to test your argument. I think your argument is quite compelling, but I'm looking for clarification that the spectral features in fact back it up. Certainly, the more distant supernova should be brighter. The effect of Malmquist bias is readily evident in samples out to even only 100 Mpc, so certainly at the much greater distances it should be evident. |
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Everyone is entitled to his own opinion, but not his own facts. |
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The best supporting evidence is in these “beams from hell” gamma rays, as Middleditch describes them. We know they are linked locally to hypernova events, we also know some of most highly focused of these beamed rays often originate at high redshifts. We also know that the probability of having one of these focused beams aimed right towards us is less than 5%, we see the rays, so we should expect to observe a significant number these brilliant hypernovae events at high redshift as well. Where are they?
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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Everyone is entitled to his own opinion, but not his own facts. |
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Observing a GRB associated with an apparent Ia supernova at high redshift would support Jerry's theory that it is really a mis-classified hypernova. Also, 1998 is a bit early, as the major event conclusively linking hypernovae to GRBs was in 2003: http://www.eso.org/outreach/press-re.../pr-16-03.html Of course, nothing has ruled out GRBs being caused by other sources (particularly the short, < 2 second bursts), which may account for high redshift GRBs that have no associated hypernova. Limitations of detection are more likely the culprit, as linking a GRB to anything takes some serious coordination.
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Do try not to take me too seriously. |
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Everyone is entitled to his own opinion, but not his own facts. |
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The role of Malmquist bias must be considered to understand his point. Any survey has a magnitude fainter than which objects are not detected. Since there is a limiting magnitude, at greater distances the objects detected will be increasingly represented by just the brightest objects. For example, in a sample of galaxies I've been analyzing, the galaxies in the closest distance bin have a mean rotational velocity of 168 km s-1 while the galaxies in the farthest distance bin have a mean rotational velocity of 214 km s-1. The reason for that effect is that the faster rotating galaxies are more luminous than the slower rotating galaxies. The increase of mean rotational velocity (and therefore luminosity) in a sample with distance is one signature of the presence of Malmquist bias in the sample. Because of the magnitude limit of the sample, the fainter galaxies fall out of the sample at greater distances. What Jerry is pointing out is that the same is expected for supernova. The most distant supernova detected ought to be increasingly represented by the most luminous supernova. However, Jerry argues, when the assumed time dilation correction for expansion is factored into the calculations, the supernova at greater distances come out less luminous with distance. He further argues that if you do not include the time dilation correction, then the most distant supernova have light curves consistent with local hypernova - exactly the type of supernova we ought to be seeing at large distances. His other relevant question is "where are the hypernova at large distances?" If he is right, then the universe would not be expanding. |
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The supernova research teams must be acutely aware of the ambiguities. But they go ahead and make these broad and unqualified announcements about the history of everything on the bases of a handful of high redshift events no one should be certain we understand. Important data. Bad cosmology.
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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Unfortunately, if such evidence is ever collected it will be by sheer luck, as we have to first detect the GRB (via HETE-II or a similar instrument), then quickly get a large telescope pointed at it for long enough to collect the necessary data. I’m having fun with the SN catalogs; I was curious to see what type Ic hypernovae have been found. For anyone wanting some light (no pun intended) reading, this site has the spectra and light curves of most SN: http://cfa-www.harvard.edu/cfa/oir/R.../RecentSN.html
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Do try not to take me too seriously. |
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cyrek1 comment
I do not consider the S1a's as reliable candles. White dwarfs come in a variety of sizes and temperaturesof from over 100,000K to 3000K. I do not see how they can be relied on. There seems to be a lot of manipulation involved to produce the results one wants. The BBer's underlying motivation to restore Einstein's lambda or fill in a gap to replace the missing mass needed for a flat space.
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aka Michael Cyrek |
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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Everyone is entitled to his own opinion, but not his own facts. |
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Once again, you want to have it both ways: The supernova Ia are very good standard candles, but they also evolve?
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jwj It's a big universe out there...is it really unwinding, really burning out? |
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Everyone is entitled to his own opinion, but not his own facts. |
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