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Ned Wright's TBBNH Page (C)
greywolf42 wrote:
Bjoern Feuerbacher wrote in message ... greywolf42 wrote: [snip] Since Lerner did not identify what value he used for 'interesting mass,' the claim that his math was wrong is spurious. Well, it's rather clear (if one knows a bit about cosmology) what an "interesting mass" would be (several eV will do it). Hence the fact that Lerner doesn't give a specific value is rather irrelevant. It wasn't "clear" at all, in 1991. See report below. I read the report below and explained that it doesn't support your point - it only talks about *electron* neutrinos. There is still no basis for claiming that Lerner's "math is wrong." As Lerner gave no math. As I explained, if one takes reasonable values (and I explained (*why* the numbers are reasonable) and puts them in, one sees that Lerner was wrong. Hence there are only two choices, IMO: 1) Lerner didn't do any math and made the whole thing up. 2) Lerner did some math and screwed it up. Ned Wright and me are only generous and assume that it was (2), not (1). [snip] They appear to travel at the speed of light, so must have no mass. This argument doesn't make much sense. They *appear* to travel at the speed of light, so *must* have no mass? What a great logic! Well, yeah... if the 'appearance' is the result of an experimental measurement. Can you say 'arbitrarily close to?' No experiment can ever measure "arbitrarily close to", so this makes no sense at all. Hint: we know today that neutrinos *have* mass, hence that they *don't* travel at the speed of light. Therefore, obviously, the experiments which showed that they travel *approximately* at the speed of light weren't sensitive enough - and every experimental physicist should have known that even back then! Additionally, there are theories which predict not only the "light" neutrinos we know, but additional neutrinos which are much more heavy. Try reading up on "see-saw" mechanism. No. Please stick to the issue. Err, the issue is if the experiments back then were able to rule out heavy neutrinos or not. The "see-saw" mechanisms is another point that the experiments could *not* have rule this out. Hence this *is* the issue. However, particle theorists postulated that neutrinos do have mass, and some cosmologists decided that these massive neutrinos could be the missing mass." "A supernova blew away this idea. I have to agree with Ned Wright: the supernova did *not* blow away this idea. His argumentation, which you quote above, makes perfect sense. Today. Not in 1991. Absolutely wrong. It was clear even in 1991 that a mass of several eV would 1) give a substantial contribution to Omega and 2) could not be detected by the supernova measurements. Additionally, it was clear even in 1991 that the supernova measurements could give limits only on the electron neutrino mass, not on the masses of the other neutrinos. Ned Wright is right, and you are wrong. Live with it. [snip] How does Lerner get from "they all arrived in a single bunch" to "they all travel at the speed of light"? This argument makes no sense at all! They arrived in a 'bunch', (a period of 6 sec) after travelling 160,000 light years. And arrived minutes before the SN light pulse. So, they were travelling at around 0.999999999999875*c (according to Ned). Right. 0.999999999999875*c. Not c. So, again, where does Lerner get "they all travel at the speed of light" from? The only thing you can deduce from the supernova measurements is (taking Wright's numbers) that "they all travel at 0.999999999999875*c". And this doesn't help Lerner's case, because this still would give a significant contribution of the neutrino mass to Omega. Lerner shows here quite nicely that he either doesn't bother to do the math, or that he did it, but screwed it up somewhere. The supernova measurements simply weren't good enough to rule out at significant neutrino mass. Furthermore, for the 5th time, at least, these measurements could only place limits on the electron neutrino mass, not on the other two masses. Again, Wright's calculations above are much better; Than what? Than Lerner's unsupported assertions. note that Wright, in contrast to Lerner, presents specific numbers! Lerner says only "a single bunch" - but doesn't tell his readers that this "bunch" had a lenght of about 10 seconds, and that this is *way* too much time to rule out a neutrino mass... The key word being 'cosmologically interesting.' I explained what "cosmologically interesting" means - that it is clear (and was clear even in 1991) that a mass of several eV *would* have been interesting, and that the supernova measurements weren't able to rule this out, according to Wright's calculation. How often do I need to repeat this argument until you understand it? That Ned Wright disagrees with Lerner about what constitutes 'interesting mass' is not an "error" on the part of Lerner. Yes, it is. One can calculate what an "interesting" mass would be: IIRC, the contribution of neutrinos to Omega is equal to the neutrino mass, divided by 92 eV/c^2. Hence a cosmologically "interesting" neutrino mass is obviously a few eV/c^2 - just the number Wright used above in his calculation! Marvellous! But that is theory-dependent. Well, it depends on the Theory of General Relativity, right. So what? And the theories keep changing (no problem with that). The TGR hasn't changed since it was discovered. But you contradict the 'wisdom' of 1991 -- when Lerner's book was written. I would say that you don't know what the "wisdom" of 1991 really were. [snip] Then again, so is Ned's bald assertion that 5 eV neutrinos are 'cosmologically interesting'. See above. Thanks. Now please provide one using only 1991 theory. That the contribution of neutrinos to Omega is given by their mass, divided by 92 eV/c^2 was known long before 1991. It's a quite easy calculation which uses only long established theories. {snip the rest} Since Eric Lerner did not identify a value of what he considered 'interesting mass' and because Ned Wright did not provide any reference for why he thought 5eV was cosmologically 'interesting,' it was difficult to directly address the issue. How about asking Ned Wright first about this, instead of at once attacking him? I'm not 'attacking him.' Yes, you are. I'm pointing out the 'elemenatry errors' in Ned Wright's webpage. If you had ask him first about what seemed to be errors to you, you would have learned that they aren't really errors - only your lack of knowledge. I'm not 'attacking' anything. And I'm not providing anything 'personal' against Ned. Only against his arguments. I didn't mention "personal" anywhere. But, if you think this is an 'attack,' why didn't Ned Wright ask Lerner about his book, instead of 'attacking the book?' How do you know that Ned Wright didn't discuss with Lerner? However, I have run across a contemporaneous reference about the degree of support available for 'interesting mass' as things existed in 1991. The reference is the book "The End of Physics," by David Lindley ("Nature" editor and referee). Publication date 1993. On page 199 to 200, Lindley discusses the evidence for 'interesting' mass for the neutrino: =========================================== There was a moment in the early 1980s when it seemed possible that this dark matter had been identified. A few experiments around the world came up with some evidence that the neutrino, in standard physics strictly a massless particle, might actually have a small mass. The mass per neutrino was tiny, but because there are as many neutrinos in the universe a large as there are photons in the three-degree microwave background, even a tiny mass could add up to a lot for cosmology. It was entirely conceivable that there could be about ten times as much neutrino mass as normal mass, in which case the overall density of the univsere could reach the critical value. As a form of dark matter, massive neutrinos had some appeal. Neutrinos are known to exist, and giving a previously unsuspected mass to an existing particle is more palatable than inventing a wholly new particle -- the hypothetical photino, for example -- to act the part of the dark matter. On top of that, the mass suggested by laboratory experiments was about the right value to be cosmologically significant. There were reasons for taking 'neutrino cosmology' seriously. IIRC, these experiments measured only the mass of the *electron* neutrino (the text doesn't say explicitly, but the only experiments I know of from that time which gave a hint on massive neutrinos were the ones where the beta decay was studied, AFAIK). Hence Wright's point that an "interesting" mass for the my and tau neutrino wasn't ruled out at that time remains still valid, and Lerner is still wrong. There was no reason to suspect that mu and tau neutrinos had significantly more mass than the electron neutrino, in 1991. The point is that there were no measurements available to rule such higher masses out. And "there is no reason to suspect" makes little sense: little is known about the reasons for the various masses of the particles (for example, no one can explain why the top quark is so heavy compared to all the other quarks), so no one had the possibility to make any educated guesses on the masses of the mu and tau neutrinos. [snip rest of article] No, let's leave it in -- since it explicitly contradicts your statements (and Ned's). The article claims that a "cosmologically interesting" mass for the neutrino was ruled out, right - but I already explained that this applies only to the mass of the electron neutrino, not to the other two. Additionally, this article has nothing to do with the supernova measurements, which, according to Lerner, ruled out a "cosmologically interesting" mass for the neutrinos. I thought we were discussing this assertion of Lerner? You are moving the goalposts, IMO. [snip] The original laboratory evidence that neutrinos might have a small but cosmologically interesting mass has now more or less been discounted. ... There, I guess you think that this contradicts my claims, and Ned's, right? For the 10th time: this applies only to *electron* neutrinos!!! So again, we see that Ned's accusations are completely unsupported. No, we see that they are well supported, sorry. LOL! Only if you snip and ignore the evidence. I only snipped irrelevant things: descriptions of experiments which 1) only refer to electron neutrinos and hence can't rule out cosmologically interesting masses for the other neutrinos and 2) don't have anything to do with the supernova measurements, which, according to Lerner, disproved such an interesting mass. I'm only saying that Lerner is wrong when he claims that the supernova measurements ruled out a cosmologically interesting mass, and from what you quoted, I'd say that Wright argues the same thing. So, bringing up *other* experiments which supposedly ruled out such a mass is beside the point - in other words, it's moving the goalposts. It appears that Lerner correctly described the common opinion that existed in 1991 (at least until 1993) -- that neutrinos did not contain cosmologically 'interesting' mass. Even if that was the opinion back then (and I'm not sure about this), The only reason you are 'not sure' is that you snipped the evidence. For the 20th time: I explained that this evidence refers only to *ELECTRON* neutrinos! Did you get it this time? And if you're 'not sure', why are you butting in? Because there is one thing I'm sure about: that Lerner's claims about the supernova measurements are wrong. *You* started bringing up other points, IIRC. This is the whole point of the thread! The "whole point" I'm debating are Lerner's arguments about the supernova measurements. Lerner's supernova argument is nevertheless still bogus. It still is. [snip rest] LOL! Another 'convenient' snip. Well, I explained why I don't it to be relevant. Replacing the rest of the paragraph: ============================ Now, if Ned (in the year 2000) feels that neutrino mass is 'interesting' again, that's a valid point of discussion between theories -- if he can come up with a reference. However, it is NOT in any manner an 'error' on the part of Eric Lerner or TBBNH. I don't see why you have a problem that I snipped this. It has absolutely nothing to do with my point. ============================ Of course you snipped it. It showed your attempt to divert from the issue under discussion. Pardon? The issue under discussion was Lerner's argument about the supernova, wasn't it? You (and Ned) are trying to claim an 'error' within the 1991 book TBBNH because of theories not proposed until after 1993! For the 20th time: that neutrinos with a mass of several eV would give a significant contribution to Omega was already known in 1991. That such a small mass could not be detected by the supernova measurments was already known in 1991, too. Might as well chastise Newton for not discussing General Relativity. What a nonsense. Bye, Bjoern |
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Ned Wright's TBBNH Page (C)
I've digged up some references.
First: G.G.Raffelt, What have We Learned from SN 1987A?, Modern Physics Letters A, vol.5, no.31, 20 Dec. 1990 p.2581-92. (notice that this is a review article; what is told in it wasn't known only at the end of 1990, but already earlier - e.g., a reference is given to a paper by Loredo and Lamb from 1989). This article gives the limit of the mass of the *electron* neutrino obtained from the observation of the supernova (eq. 9): m_{\nu_e} 23 eV (at 95% confidence level). Second: E.W.Kolb, M.S.Turner, The early universe, Frontiers in Physics, Addison-Wesley (1990). This is a well-known book on cosmology by two famous cosmologists; it summarizes what was known on cosmology back then and hence includes lots of things which were already long known at that time. Equation (5.33) is the interesting one in that book: \Omega_{\nu} h^2 = m_{\nu}/91.5 eV (hey, the 92 eV which I remembered where quite accurate!). I don't know exactly what value of h was available back then, but let's use the (quite high and therefore favourable for you!) value of h = 0.8. Then we get: \Omega_{\nu} = m_{\nu}/58.56 eV. Putting these two things together (which both were known *BEFORE* 1991, when Lerner published his book!), we get: \Omega_{\nu} 0.39. Obviously, a value of 0.39 *IS* quite significant cosmologically! Hence, contrary to Lerner's claims, the supernova observations did *not* rule out a mass for the neutrino which would have been cosmologically relevant. Lerner is wrong there, live with it. (and please stop whining about the other report you quoted - the *only* thing I wanted to discuss is if Lerner's claim, that the supernova observations ruled out a cosmologically interesting electron mass, was right!) And again, please notice that this (and the other report you quoted) only applies to the electron neutrino - *much* less was known about the other neutrinos masses back then. IIRC, the mass bound for the mu neutrino was something like 25 keV, and the mass bound for the tau neutrino was somewhere in the MeV range! Bye, Bjoern |
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Ned Wright's TBBNH Page (C)
Bjoern Feuerbacher wrote:
I've digged up *blush* Make that "dug up". Sorry, English isn't my first language. [snip rest] |
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Ned Wright's TBBNH Page (C)
"Bjoern Feuerbacher" wrote in message ... Bjoern Feuerbacher wrote: I've digged up *blush* Make that "dug up". Sorry, English isn't my first language. [snip rest] Digged Up had more nuance and style... |
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Ned Wright's TBBNH Page (C)
Bjoern Feuerbacher wrote in message ... greywolf42 wrote: Bjoern Feuerbacher wrote in message ... greywolf42 wrote: [snip] Since Lerner did not identify what value he used for 'interesting mass,' the claim that his math was wrong is spurious. Well, it's rather clear (if one knows a bit about cosmology) what an "interesting mass" would be (several eV will do it). Hence the fact that Lerner doesn't give a specific value is rather irrelevant. It wasn't "clear" at all, in 1991. See report below. I read the report below and explained that it doesn't support your point - it only talks about *electron* neutrinos. Electron neutrinos are the masses we are discussing. Kamiokande only detects electron neutrinos. There is still no basis for claiming that Lerner's "math is wrong." As Lerner gave no math. As I explained, if one takes reasonable values (and I explained (*why* the numbers are reasonable) No, you did not. You merely repeated the claim. and puts them in, one sees that Lerner was wrong. Hence there are only two choices, IMO: 1) Lerner didn't do any math and made the whole thing up. 2) Lerner did some math and screwed it up. Ned Wright and me are only generous and assume that it was (2), not (1). Ah, the refuge of the true believer. The fallacy of the excluded middle, combined with a straw man. [snip] They appear to travel at the speed of light, so must have no mass. This argument doesn't make much sense. They *appear* to travel at the speed of light, so *must* have no mass? What a great logic! Well, yeah... if the 'appearance' is the result of an experimental measurement. Can you say 'arbitrarily close to?' No experiment can ever measure "arbitrarily close to", so this makes no sense at all. Bingo! Claiming evidence of mass when all we have is upper bounds is indeed senseless. Hint: we know today that neutrinos *have* mass, No, we see a discrepancy in theory. And we interpret this as 'evidence of mass.' However, this is still irrelevant to knowledge in 1991. hence that they *don't* travel at the speed of light. Too bad that's what experiments show. Therefore, obviously, the experiments which showed that they travel *approximately* at the speed of light weren't sensitive enough - and every experimental physicist should have known that even back then! ROTFLMAO! Rewrite the histories and the experiments, boys! We've found a discrepancy in our theory, so experiment must be in error. Additionally, there are theories which predict not only the "light" neutrinos we know, but additional neutrinos which are much more heavy. Try reading up on "see-saw" mechanism. No. Please stick to the issue. Err, the issue is if the experiments back then were able to rule out heavy neutrinos or not. The "see-saw" mechanisms is another point that the experiments could *not* have rule this out. Hence this *is* the issue. Which leads us right back to that original issue, 'how heavy is heavy?' However, particle theorists postulated that neutrinos do have mass, and some cosmologists decided that these massive neutrinos could be the missing mass." "A supernova blew away this idea. I have to agree with Ned Wright: the supernova did *not* blow away this idea. His argumentation, which you quote above, makes perfect sense. Today. Not in 1991. Absolutely wrong. It was clear even in 1991 that a mass of several eV would 1) give a substantial contribution to Omega and 2) could not be detected by the supernova measurements. Additionally, it was clear even in 1991 that the supernova measurements could give limits only on the electron neutrino mass, not on the masses of the other neutrinos. Ned Wright is right, and you are wrong. Live with it. LOL! Not according David Lindley (editor of Nature), as late as 1993. Merely repeating a claim never makes it true. [snip] How does Lerner get from "they all arrived in a single bunch" to "they all travel at the speed of light"? This argument makes no sense at all! They arrived in a 'bunch', (a period of 6 sec) after travelling 160,000 light years. And arrived minutes before the SN light pulse. So, they were travelling at around 0.999999999999875*c (according to Ned). Right. 0.999999999999875*c. Not c. That is c to 13 decimal places. How many decimal places do you want before you admit that it's 'c'? So, again, where does Lerner get "they all travel at the speed of light" from? The only thing you can deduce from the supernova measurements is (taking Wright's numbers) that "they all travel at 0.999999999999875*c". And this doesn't help Lerner's case, because this still would give a significant contribution of the neutrino mass to Omega. You just keep asserting this, over and over. Please provide a pre-1991 reference for significant contribution to omega at this level. Lerner shows here quite nicely that he either doesn't bother to do the math, or that he did it, but screwed it up somewhere. The supernova measurements simply weren't good enough to rule out at significant neutrino mass. Please provide a pre-1991 reference that states this. I provided a standard one that refutes your claim. Furthermore, for the 5th time, at least, these measurements could only place limits on the electron neutrino mass, not on the other two masses. And your continued repeat of irrelevant observations changes nothing. You never did provide any backup for this claim. Why repeat it 5 times? Again, Wright's calculations above are much better; Than what? Than Lerner's unsupported assertions. Lerner's assertions are not unsupported. Wright's 'argument by definition' is not a 'calculation.' note that Wright, in contrast to Lerner, presents specific numbers! Lerner says only "a single bunch" - but doesn't tell his readers that this "bunch" had a lenght of about 10 seconds, and that this is *way* too much time to rule out a neutrino mass... The key word being 'cosmologically interesting.' I explained what "cosmologically interesting" means - that it is clear (and was clear even in 1991) that a mass of several eV *would* have been interesting, Please provide even a single reference available in 1991 that this was the case. As late as 1993, several eV was *not* considered 'cosmologically interesting' -- as indicated in the reference of Lindley as late as 1993. and that the supernova measurements weren't able to rule this out, according to Wright's calculation. How often do I need to repeat this argument until you understand it? Repeating irrelevant statements will never matter. Try finding a reference. Post it. That Ned Wright disagrees with Lerner about what constitutes 'interesting mass' is not an "error" on the part of Lerner. Yes, it is. One can calculate what an "interesting" mass would be: IIRC, the contribution of neutrinos to Omega is equal to the neutrino mass, divided by 92 eV/c^2. Where did you get the value, above? Try providing a reference from 1991. Hence a cosmologically "interesting" neutrino mass is obviously a few eV/c^2 - just the number Wright used above in his calculation! Marvellous! But that is theory-dependent. Well, it depends on the Theory of General Relativity, right. So what? Not 'just' GR. But 'GR plus dark matter.' Which was the point, of course. And the theories keep changing (no problem with that). The TGR hasn't changed since it was discovered. Sure it has. Now it needs 'dark matter' to match observations. But you contradict the 'wisdom' of 1991 -- when Lerner's book was written. I would say that you don't know what the "wisdom" of 1991 really were. So quit just 'saying' it, and provide a reference. [snip] Then again, so is Ned's bald assertion that 5 eV neutrinos are 'cosmologically interesting'. See above. Thanks. Now please provide one using only 1991 theory. That the contribution of neutrinos to Omega is given by their mass, divided by 92 eV/c^2 was known long before 1991. It's a quite easy calculation which uses only long established theories. Then it should be simple to provide a reference. Why do you keep dodging? {snip the rest} Since Eric Lerner did not identify a value of what he considered 'interesting mass' and because Ned Wright did not provide any reference for why he thought 5eV was cosmologically 'interesting,' it was difficult to directly address the issue. How about asking Ned Wright first about this, instead of at once attacking him? I'm not 'attacking him.' Yes, you are. No. See my next sentence. Ned Wright is not his web page. Ned Wright's web page is not Ned Wright. I'm pointing out the 'elemenatry errors' in Ned Wright's webpage. If you had ask him first about what seemed to be errors to you, you would have learned that they aren't really errors - only your lack of knowledge. They are fundamental errors. The web page contains numerous mis-stated excerpts from TBBNH. Those are elementary errors. I'm not 'attacking' anything. And I'm not providing anything 'personal' against Ned. Only against his arguments. I didn't mention "personal" anywhere. LOL! You claimed -- and reiterated -- that *I* was *attacking* Ned Wright. That *IS* a claim of a personal attack -- even if you don't use the word 'personal.' For 'Ned Wright' is a person -- not a corporation or a web page. I am not attacking the person of Ned Wright. I am pointing out elementary errors that exist on Ned Wright's webpage. But, if you think this is an 'attack,' why didn't Ned Wright ask Lerner about his book, instead of 'attacking the book?' How do you know that Ned Wright didn't discuss with Lerner? Because he refuses to allow anyone to see any theoretical responses from Lerner. If Ned's web page had been honest, and if Ned had actually entered into discussion with Lerner, then Lerner would have been allowed at least one round of response. However, I have run across a contemporaneous reference about the degree of support available for 'interesting mass' as things existed in 1991. The reference is the book "The End of Physics," by David Lindley ("Nature" editor and referee). Publication date 1993. On page 199 to 200, Lindley discusses the evidence for 'interesting' mass for the neutrino: =========================================== There was a moment in the early 1980s when it seemed possible that this dark matter had been identified. A few experiments around the world came up with some evidence that the neutrino, in standard physics strictly a massless particle, might actually have a small mass. The mass per neutrino was tiny, but because there are as many neutrinos in the universe a large as there are photons in the three-degree microwave background, even a tiny mass could add up to a lot for cosmology. It was entirely conceivable that there could be about ten times as much neutrino mass as normal mass, in which case the overall density of the univsere could reach the critical value. As a form of dark matter, massive neutrinos had some appeal. Neutrinos are known to exist, and giving a previously unsuspected mass to an existing particle is more palatable than inventing a wholly new particle -- the hypothetical photino, for example -- to act the part of the dark matter. On top of that, the mass suggested by laboratory experiments was about the right value to be cosmologically significant. There were reasons for taking 'neutrino cosmology' seriously. IIRC, these experiments measured only the mass of the *electron* neutrino (the text doesn't say explicitly, but the only experiments I know of from that time which gave a hint on massive neutrinos were the ones where the beta decay was studied, AFAIK). Hence Wright's point that an "interesting" mass for the my and tau neutrino wasn't ruled out at that time remains still valid, and Lerner is still wrong. There was no reason to suspect that mu and tau neutrinos had significantly more mass than the electron neutrino, in 1991. The point is that there were no measurements available to rule such higher masses out. And "there is no reason to suspect" makes little sense: little is known about the reasons for the various masses of the particles (for example, no one can explain why the top quark is so heavy compared to all the other quarks), Sure they can -- because it was what was found by experiment (far above the 'theoretical' predictions). That simply is a 'hit' against the standard model. so no one had the possibility to make any educated guesses on the masses of the mu and tau neutrinos. That doesn't mean that it was 'known' that mu and tau neutrinos could be the source of missing mass. Theory said zero. Exactly zero. And there was no evidence otherwise. [snip rest of article] No, let's leave it in -- since it explicitly contradicts your statements (and Ned's). The article claims that a "cosmologically interesting" mass for the neutrino was ruled out, right - but I already explained that this applies only to the mass of the electron neutrino, not to the other two. And you admitted, just above, that at the time there was no theoretical or experimental reason to expect the mu or tau neutrino to be massive -- or more massive than the electron neutrino. Additionally, this article has nothing to do with the supernova measurements, which, according to Lerner, ruled out a "cosmologically interesting" mass for the neutrinos. I thought we were discussing this assertion of Lerner? You are moving the goalposts, IMO. The assertion of Lerner is that neutrinos weren't massive enough to make up the 'cosmologically interesting.' This is what Wright and yourself have been asserting. Statements of yours such as "One can calculate what an 'interesting' mass would be: IIRC, the contribution of neutrinos to Omega is equal to the neutrino mass, divided by 92 eV/c^2. Hence a cosmologically 'interesting' neutrino mass is obviously a few eV/c^2 - just the number Wright used above in his calculation!" Lerner *did* focus on SN1987a. And David Lindley (1993) went into theoretical failings of 'heavy neutrinos' as well as 'laboratory experiments' -- and didn't mention SN1987a -- but came to the same conclusion. That in 1993 (and 1991) neutrinos weren't massive enough to be 'cosmologically interesting.' It doesn't matter what you or Ned use -- today -- to determine what you think is 'cosmologically interesting' -- today. Lerner's statements were not in error in 1991 -- based on information available in 1991. [snip] {putting back part of the reference that makes your claims look silly} ================================== "... The uncollapsibility of massive neutrinos was too much of a good thing. The large structures that would form in a neutrino universe would be too large and too loose to correspond to the observed galactic clusters. And it is impossible for neutrinos to be the dark matter in individual galaxies, because they are too fast-moving to be retained by the gravity of single galaxies. Massive neutrinos ended by failing on two counts; they created too much large-scale structure in the universe, and they could not account for galactic dark matter." ================================== The original laboratory evidence that neutrinos might have a small but cosmologically interesting mass has now more or less been discounted. ... There, I guess you think that this contradicts my claims, and Ned's, right? For the 10th time: this applies only to *electron* neutrinos!!! Not according to David Lindley. Plus, you have already admitted that there was no reason in 1991 to expect a (more) massive tau or mu neutrino. So again, we see that Ned's accusations are completely unsupported. No, we see that they are well supported, sorry. LOL! Only if you snip and ignore the evidence. I only snipped irrelevant things: descriptions of experiments which 1) only refer to electron neutrinos and hence can't rule out cosmologically interesting masses for the other neutrinos and 2) don't have anything to do with the supernova measurements, which, according to Lerner, disproved such an interesting mass. The fact that Lerner focused on SN1987a and Lindley didn't mention SN1987a does not mean it's not a valid observation. After all, the point is that neutrinos (electron and otherwise) were considered to have 'uninteresting' mass in 1991 and 1993. I'm only saying that Lerner is wrong when he claims that the supernova measurements ruled out a cosmologically interesting mass, and from what you quoted, I'd say that Wright argues the same thing. So, bringing up *other* experiments which supposedly ruled out such a mass is beside the point - in other words, it's moving the goalposts. Not in the least. Wright's point was that neutrinos had 'cosmologically interesting' mass in 1991. Now, Ned is welcome to examine any data provided by Lerner in TBBNH and produce a different opinion. He is not welcome to produce an opinion contrary to 'accepted wisdom in 1991' and then chastise Lerner for providing 'accepted wisdom in 1991.' Even if we think differently today. I suppose I could go hunting for another reference that in 1991 neutrinos (all types) were not considered to have 'interesting' mass, based on SN1987a (I recall there were some such). But that would be beating a dead horse. Perhaps you'd care to come up with a reference that claimed neutrino mass WAS 'interesting' -- and written in the 1988 to 1991 timeframe. That would give us something to discuss to effect. It appears that Lerner correctly described the common opinion that existed in 1991 (at least until 1993) -- that neutrinos did not contain cosmologically 'interesting' mass. Even if that was the opinion back then (and I'm not sure about this), The only reason you are 'not sure' is that you snipped the evidence. For the 20th time: I explained that this evidence refers only to *ELECTRON* neutrinos! Did you get it this time? And you also admitted that there was no reason to expect any more from mu or tau neutrinos in 1991. So you can quit bringing up irrelvancies, now. And if you're 'not sure', why are you butting in? Because there is one thing I'm sure about: that Lerner's claims about the supernova measurements are wrong. *You* started bringing up other points, IIRC. Nope. Lerner's claims are correct. Both specifically and the basic point. In 1991, neutrinos were considered to have 'uninteresting' mass. This is the whole point of the thread! The "whole point" I'm debating are Lerner's arguments about the supernova measurements. Then kindly do so, and quit the tangents into mu and tau neutrinos. {replacing another 'invisible' snip} ============================== So again, we see that Ned's accusations are completely unsupported. No, we see that they are well supported, sorry. LOL! Only if you snip and ignore the evidence. It appears that Lerner correctly described the common opinion that existed in 1991 (at least until 1993) -- that neutrinos did not contain cosmologically 'interesting' mass. Even if that was the opinion back then (and I'm not sure about this), The only reason you are 'not sure' is that you snipped the evidence. And if you're 'not sure', why are you butting in? This is the whole point of the thread! ============================== Lerner's supernova argument is nevertheless still bogus. It still is. You have to talk to yourself, just to make a point? [snip rest] LOL! Another 'convenient' snip. Well, I explained why I don't it to be relevant. No, you simply snipped it. Replacing the rest of the paragraph: ============================ Now, if Ned (in the year 2000) feels that neutrino mass is 'interesting' again, that's a valid point of discussion between theories -- if he can come up with a reference. However, it is NOT in any manner an 'error' on the part of Eric Lerner or TBBNH. I don't see why you have a problem that I snipped this. It has absolutely nothing to do with my point. Truly pathological. Read the next sentence. ============================ Of course you snipped it. It showed your attempt to divert from the issue under discussion. Pardon? The issue under discussion was Lerner's argument about the supernova, wasn't it? No. It was Wright's claim that Lerner's statement about 'uninteresting' mass was known to be incorrect in 1991. You (and Ned) are trying to claim an 'error' within the 1991 book TBBNH because of theories not proposed until after 1993! For the 20th time: that neutrinos with a mass of several eV would give a significant contribution to Omega was already known in 1991. Then why the hell don't you provide a contemporary reference for God's sake! Why all this mealymouthed bushwa about 'the mass was not proved to be zero' or 'what about mu and tau neutrinos?' That such a small mass could not be detected by the supernova measurments was already known in 1991, too. Please provide a reference, oh cowardly 'invisible' snipper! Might as well chastise Newton for not discussing General Relativity. What a nonsense. I agree that faulting someone in 1991 for not knowing something that wasn't accepted until after 1993 is nonsense. greywolf42 ubi dubium ibi libertas |
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Ned Wright's TBBNH Page (C)
greywolf42 wrote:
Bjoern Feuerbacher wrote in message ... greywolf42 wrote: Bjoern Feuerbacher wrote in message ... greywolf42 wrote: [snip] Since Lerner did not identify what value he used for 'interesting mass,' the claim that his math was wrong is spurious. Well, it's rather clear (if one knows a bit about cosmology) what an "interesting mass" would be (several eV will do it). Hence the fact that Lerner doesn't give a specific value is rather irrelevant. It wasn't "clear" at all, in 1991. See report below. I read the report below and explained that it doesn't support your point - it only talks about *electron* neutrinos. Electron neutrinos are the masses we are discussing. We are discussing if 1991 it was known if neutrinos have an "cosmologically interesting" mass. Not only electron neutrinos. *All* neutrinos. Kamiokande only detects electron neutrinos. Right - and therefore, as Wright and me correctly point out, Kamiokande couldn't have rule out "cosmologically interesting" masses for the other two neutrinos. There is still no basis for claiming that Lerner's "math is wrong." As Lerner gave no math. As I explained, if one takes reasonable values (and I explained (*why* the numbers are reasonable) No, you did not. You merely repeated the claim. That's a lie. I gave you the formula with which one determines if a neutrino mass is cosmologically interesting or not (neutrino mass/92 eV/c^2). Using the formula, it turns out that 5eV/c^2 (the number Wright used) *is* a reasonable value. and puts them in, one sees that Lerner was wrong. Hence there are only two choices, IMO: 1) Lerner didn't do any math and made the whole thing up. 2) Lerner did some math and screwed it up. Ned Wright and me are only generous and assume that it was (2), not (1). Ah, the refuge of the true believer. The fallacy of the excluded middle, combined with a straw man. Care to come up with other possibilities, instead of simply asserting that there are others? [snip] They appear to travel at the speed of light, so must have no mass. This argument doesn't make much sense. They *appear* to travel at the speed of light, so *must* have no mass? What a great logic! Well, yeah... if the 'appearance' is the result of an experimental measurement. Can you say 'arbitrarily close to?' No experiment can ever measure "arbitrarily close to", so this makes no sense at all. Bingo! Claiming evidence of mass when all we have is upper bounds is indeed senseless. What on earth are you talking about??? No one claimed that in 1991, we had evidence of mass; the only thing which was said is that with the numbers available in 1991 (for which I gave references!), a cosmoligically interesting mass could not be ruled out - contrary to Lerner's assertion. Hint: we know today that neutrinos *have* mass, No, we see a discrepancy in theory. Pardon??? What on earth are you talking about??? Neutrino oscillations are clear evidence for neutrino masses. So where is "a discrepancy in theory"??? And we interpret this as 'evidence of mass.' Do you have another explanation for neutrino oscillations which fits all of the data? However, this is still irrelevant to knowledge in 1991. I never claimed that it were relevant. hence that they *don't* travel at the speed of light. Too bad that's what experiments show. The experiments show that they travel *approximately* at the speed of light. No experiment can ever show that they travel *exactly* at the speed of light. Hence the experiments which measure the velocities of neutrinos couldn't rule out a neutrino mass ever. Therefore, obviously, the experiments which showed that they travel *approximately* at the speed of light weren't sensitive enough - and every experimental physicist should have known that even back then! ROTFLMAO! Rewrite the histories and the experiments, boys! Where on earth is your problem??? The supernova observations only showed that the mass of the electron neutrino must be smaller than 23eV/c^2. This obviously doesn't rule out a neutrino mass! We've found a discrepancy in our theory, so experiment must be in error. What discrepancy are you talking about??? And where did I say that an experiment is in error? I only pointed out that it wasn't *sensitive* enough! Neutrino oscillations point to neutrino masses around 10^(-3) eV/c^2; that the supernova measurements weren't sensitive enough to detect such a mass is a simple fact - try reading the original papers! (see my references) Additionally, there are theories which predict not only the "light" neutrinos we know, but additional neutrinos which are much more heavy. Try reading up on "see-saw" mechanism. No. Please stick to the issue. Err, the issue is if the experiments back then were able to rule out heavy neutrinos or not. The "see-saw" mechanisms is another point that the experiments could *not* have rule this out. Hence this *is* the issue. Which leads us right back to that original issue, 'how heavy is heavy?' This wasn't the original issue. The original issue was "Were the supernova measurements sensitive enough to rule out a cosmologically interesting neutrino mass?", and the answer to this is no - see my references. [snip a bit] Today. Not in 1991. Absolutely wrong. It was clear even in 1991 that a mass of several eV would 1) give a substantial contribution to Omega and 2) could not be detected by the supernova measurements. Additionally, it was clear even in 1991 that the supernova measurements could give limits only on the electron neutrino mass, not on the masses of the other neutrinos. Ned Wright is right, and you are wrong. Live with it. LOL! Not according David Lindley (editor of Nature), as late as 1993. Merely repeating a claim never makes it true. I provided references and calculations. You ignored both so far. Hence it's you who is simply repeating a false claim, hoping that it will become true. [snip] They arrived in a 'bunch', (a period of 6 sec) after travelling 160,000 light years. And arrived minutes before the SN light pulse. So, they were travelling at around 0.999999999999875*c (according to Ned). Right. 0.999999999999875*c. Not c. That is c to 13 decimal places. How many decimal places do you want before you admit that it's 'c'? If neutrinos have a mass of around 10^(-3) eV/c^2, as the neutrino oscillation measurements imply, and an energy of 10 MeV, the travel at a speed of v/c = sqrt(1 - 10(-10)^2), which is approx. 1 - 0.5 * 10^(-20). So, in order to "see" the neutrino mass in experiments which measure their speed, you have to measure their speed with a sensitivity of 20 decimal places. Good luck. So, again, where does Lerner get "they all travel at the speed of light" from? The only thing you can deduce from the supernova measurements is (taking Wright's numbers) that "they all travel at 0.999999999999875*c". And this doesn't help Lerner's case, because this still would give a significant contribution of the neutrino mass to Omega. You just keep asserting this, over and over. No, I gave you the formula which demonstrates this. I gave you references for the data and the formula. You ignored both so far. It's *YOU* who is asserting something over and over. Please provide a pre-1991 reference for significant contribution to omega at this level. Already done. I gave two references (in another post on last friday) which, taken together, demonstrate the data from SN1987A give only an upper limit for the contribution of the electron neutrinos to Omega of 0.39. Obviously such a number *is* cosmologically interesting. Lerner shows here quite nicely that he either doesn't bother to do the math, or that he did it, but screwed it up somewhere. The supernova measurements simply weren't good enough to rule out at significant neutrino mass. Please provide a pre-1991 reference that states this. See above. Can't you do the math for yourself? The formula is really easy (see the other post). Just plug the data in, and you'll see that Lerner's claim is wrong. I provided a standard one that refutes your claim. I explained why your reference isn't relevant here. You ignored, misunderstood, misrepresented, whatever, this explanation. I'll try again: this reference 1) talked about measurements from beta decay, which supposedly showed an electron neutrino mass of 17keV. Such a mass would have had strong cosmological implecations. This data was shown to be wrong later, and therefore the author in Nature concluded that the neutrinos apparently have no big cosmological impact. I explained in detail why this conclusion is questionable. 2) talked only about electron neutrinos and didn't rule out a cosmologically interesting mass for the other neutrinos. Furthermore, for the 5th time, at least, these measurements could only place limits on the electron neutrino mass, noton the other two masses. And your continued repeat of irrelevant observations changes nothing. Why on earth do you think this is irrelevant??? You never did provide any backup for this claim. Why repeat it 5 times? The measurements the article in Nature talk about are about beta decays. Surely you know that in beta decays, only electron neutrinos appear? Again, Wright's calculations above are much better; Than what? Than Lerner's unsupported assertions. Lerner's assertions are not unsupported. He doesn't provide any concrete numbers. I would call this "unsupported". Wright's 'argument by definition' is not a 'calculation.' What "argument by definition" are you talking about? I explained in detail (remember the formula for the contribution to Omega?) why a mass of 5eV/C62, which Lerner assumed, is a sensible value to use in the calculation. [snip repetitions] Yes, it is. One can calculate what an "interesting" mass would be: IIRC, the contribution of neutrinos to Omega is equal to the neutrino mass, divided by 92 eV/c^2. Where did you get the value, above? Try providing a reference from 1991. Already done in another post to this thread on Friday and (big surprise!) completely ignored by you. The reference is to the well-known book by Kolb and Turner "The early universe", which was published in 1990 and includes lots of material which was known already long before. Hence a cosmologically "interesting" neutrino mass is obviously a few eV/c^2 - just the number Wright used above in his calculation! Marvellous! But that is theory-dependent. Well, it depends on the Theory of General Relativity, right. So what? Not 'just' GR. But 'GR plus dark matter.' Absolutely wrong. The formula for the contribution of massive neutrinos to Omega does in no way at all depend on the assumption of the existence of dark matter. Only GR is used, plus some thermodynamics and a little Special Relativity (which must be used because the velocity of the neutrinos is so high). Try opening the book and looking at the calculation if you don't believe me. It's in chapter 5, the relevant formula I'm talking about is (5.33). Which was the point, of course. The point is that you don't understand cosmology. Thanks for demonstrating this. All you can do is dig up some papers and misunderstand or misrepresent them in a way so that they supposedly contradict Wright's statements and support Lerner. And the theories keep changing (no problem with that). The TGR hasn't changed since it was discovered. Sure it has. Now it needs 'dark matter' to match observations. The TGR doesn't need dark matter for anything. The Big Bang theory "needs" this dark matter (better wording: by fitting the various parameters in the BBT to observations, one sees that there is dark matter in the universe). Thanks for demonstrating that you don't understand the difference between these two! And, BTW, do you ignore the *other* observations (from rotation curves of galaxies and the behaviour of galactic clusters) which *also* show that there is indeed dark matter? [snip more repetitions] I'm pointing out the 'elemenatry errors' in Ned Wright's webpage. If you had ask him first about what seemed to be errors to you, you would have learned that they aren't really errors - only your lack of knowledge. They are fundamental errors. The web page contains numerous mis-stated excerpts from TBBNH. Those are elementary errors. What is mis-stated about the supernova measurements, exactly? The references I provided (hint: I'm talking about the ones you ignored) show clearly that the supernova measurements could *not* rule out a cosmologically interesting neutrino mass, no matter what someone in Nature said. Don't rely on what's stated in journal articles. Do the calculations for yourself! It's not hard to do. I'm not 'attacking' anything. And I'm not providing anything 'personal' against Ned. Only against his arguments. I didn't mention "personal" anywhere. LOL! You claimed -- and reiterated -- that *I* was *attacking* Ned Wright. That *IS* a claim of a personal attack -- even if you don't use the word 'personal.' You claim that Wright misrepresents Lerner. I would call this a "personal attack". For 'Ned Wright' is a person -- not a corporation or a web page. I am not attacking the person of Ned Wright. I am pointing out elementary errors that exist on Ned Wright's webpage. Hint: he wrote these pages. Hence an attack on the pages *is* an attack on him. But, if you think this is an 'attack,' why didn't Ned Wright ask Lerner about his book, instead of 'attacking the book?' How do you know that Ned Wright didn't discuss with Lerner? Because he refuses to allow anyone to see any theoretical responses from Lerner. Any evidence for this assertion? If Ned's web page had been honest, and if Ned had actually entered into discussion with Lerner, then Lerner would have been allowed at least one round of response. Any evidence that Lerner even tried to respond? [snip lots] The point is that there were no measurements available to rule such higher masses out. And "there is no reason to suspect" makes little sense: little is known about the reasons for the various masses of the particles (for example, no one can explain why the top quark is so heavy compared to all the other quarks), Sure they can -- because it was what was found by experiment (far above the 'theoretical' predictions). What on earth are you talking about??? What theoretical predictions??? And what do you mean by "sure they can"??? Do you mean that one *can* explain why the top quark is so heavy? If yes, would you please give me this explanation? That simply is a 'hit' against the standard model. What is a hit against the SM? That the top quark is so heavy??? Why on earth do you think so??? so no one had the possibility to make any educated guesses on the masses of the mu and tau neutrinos. That doesn't mean that it was 'known' that mu and tau neutrinos could be the source of missing mass. This makes no sense at all. If the masses weren't known to be small, obviously no one could have rule out them as the source of missing mass! This would have been the most natural choice! Theory said zero. Exactly zero. What theory would that be? Yes, I know that the Standard Model at that time treated the neutrinos as massless. But that was not based on real experimental evidence that they are indeed massless - only on experimental evidence that their masses, if they exist, are negligible for essentially all interesting cases. And there was no evidence otherwise. The only evidence available back then were upper bounds on the mass. Hence obviously no one could have ruled out a cosmologically interesting mass for them. [snip rest of article] No, let's leave it in -- since it explicitly contradicts your statements (and Ned's). The article claims that a "cosmologically interesting" mass for the neutrino was ruled out, right - but I already explained that this applies only to the mass of the electron neutrino, not to the other two. And you admitted, just above, that at the time there was no theoretical or experimental reason to expect the mu or tau neutrino to be massive -- or more massive than the electron neutrino. You don't ever get the point, do you? The point is that Lerner claimed that the SN observations ruled out a "cosmologically interesting" mass for the neutrinos, and that this claim is wrong, because it doesn't provide any bounds on the masses of the mu and tau neutrinos! It is absolutely *irrelevant* for the truth of this claim if there was experimental evidence for masses of the mu and tau neutrino at that time or not! Additionally, this article has nothing to do with the supernova measurements, which, according to Lerner, ruled out a "cosmologically interesting" mass for the neutrinos. I thought we were discussing this assertion of Lerner? You are moving the goalposts, IMO. The assertion of Lerner is that neutrinos weren't massive enough to make up the 'cosmologically interesting.' That's a wider assertion than the one you originally presented. Originally you presented Lerner's assertion that the SN measurements ruled out a cosmologically interesting mass. It's *that* assertion I'm discussing, not the wider one. Moving goalposts indeed! This is what Wright and yourself have been asserting. No, what I (and Wright, too, at least in the quotes you provided - the ones I'm discussing here!) assert is that the SN measurements were not able to rule out a cosmologically interesting mass. Statements of yours such as "One can calculate what an 'interesting' mass would be: IIRC, the contribution of neutrinos to Omega is equal to the neutrino mass, divided by 92 eV/c^2. Hence a cosmologically 'interesting' neutrino mass is obviously a few eV/c^2 - just the number Wright used above in his calculation!" Yes. So what? It was explicitly discussed if the SN measurements were able to detect such a mass. Lerner *did* focus on SN1987a. Yes, and Wright and I do, too. And David Lindley (1993) went into theoretical failings of 'heavy neutrinos' as well as 'laboratory experiments' -- and didn't mention SN1987a -- but came to the same conclusion. Lindley, as you yourself admit, doesn't mention SN1987A, hence what Lindley wrote is *absolutely irrelevant* for evaluating Lerner's assertion that the SN measurements rule out a cosmologically interesting neutrino mass. That in 1993 (and 1991) neutrinos weren't massive enough to be 'cosmologically interesting.' That isn't the original assertion. The original assertion was that the SN measurements ruled out such a mass. *That* assertion I'm discussing. Can't you stay on focus? It doesn't matter what you or Ned use -- today -- to determine what you think is 'cosmologically interesting' -- today. Lerner's statements were not in error in 1991 -- based on information available in 1991. Wrong. See my references. Both from 1990, and containing data which was known already earlier. [snip] this applies only to *electron* neutrinos!!! Not according to David Lindley. Well, he uses "neutrino" as a shorthand for "electron neutrino", because these are the best known and most studied ones. If you don't believe me, try looking up what experiments Lindley talked about. Hint: you will find out that they only measured electron neutrinos. Plus, you have already admitted that there was no reason in 1991 to expect a (more) massive tau or mu neutrino. Which is beside the point. [snip repetitions] I'm only saying that Lerner is wrong when he claims that the supernova measurements ruled out a cosmologically interesting mass, and from what you quoted, I'd say that Wright argues the same thing. So, bringing up *other* experiments which supposedly ruled out such a mass is beside the point - in other words, it's moving the goalposts. Not in the least. Wright's point was that neutrinos had 'cosmologically interesting' mass in 1991. Wrong. Judging from what you quoted, Wright's point was that the SN observations couldn't have ruled out a cosmologically interesting mass. [snip more of missing the point] I suppose I could go hunting for another reference that in 1991 neutrinos (all types) were not considered to have 'interesting' mass, Again: that's beside the point. The point is Lerner's assertion that the SN data was able to rule out such a mass. [snip more of the same] The "whole point" I'm debating are Lerner's arguments about the supernova measurements. Then kindly do so, and quit the tangents into mu and tau neutrinos. Err, the mu and tau neutrinos are not "tangents"! They are crucial! I'll try again, slowly: 1) Lerner claimed that the SN measurements ruled out a cosmologically interesting neutrino mass. 2) Only electron neutrinos were measured from the SN. 3) Therefore only bounds on the mass of the electron neutrino could be found. 4) Therefore a cosmologically interesting mass for the mu and tau neutrino could not be ruled out based on the SN data. 5) Therefore Lerner's claim that the SN data ruled out a cosmologically interesting mass for the neutrinos is obviously wrong. Did you get it this time? If not, then I really have to give up on such a granite head. {replacing another 'invisible' snip} Err, I mark my snips. [snip lots of repetitions] Pardon? The issue under discussion was Lerner's argument about the supernova, wasn't it? No. It was Wright's claim that Lerner's statement about 'uninteresting' mass was known to be incorrect in 1991. Well, what I am discussing here is Lerner's claim that the SN measurements ruled out such a mass, and Wright's calculations which showed that this claim is wrong. If you are discussing something different, then that's your problem, not mine. You (and Ned) are trying to claim an 'error' within the 1991 book TBBNH because of theories not proposed until after 1993! For the 20th time: that neutrinos with a mass of several eV would give a significant contribution to Omega was already known in 1991. Then why the hell don't you provide a contemporary reference for God's sake! Then why the hell did you completely ignore my post in which I gave these references for God's sake! Why all this mealymouthed bushwa about 'the mass was not proved to be zero' or 'what about mu and tau neutrinos?' Because these points are relevant?!?!?!?! That such a small mass could not be detected by the supernova measurments was already known in 1991, too. Please provide a reference, oh cowardly 'invisible' snipper! Already provided, oh cowardly ignorer of references! Might as well chastise Newton for not discussing General Relativity. What a nonsense. I agree that faulting someone in 1991 for not knowing something that wasn't accepted until after 1993 is nonsense. It was known in 1991. See my references. Do the calculation. Bye, Bjoern |
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Ned Wright's TBBNH Page (C)
"Bjoern Feuerbacher" wrote in message ... greywolf42 wrote: Bjoern Feuerbacher wrote in message ... greywolf42 wrote: Bjoern Feuerbacher wrote in message ... greywolf42 wrote: [snip] There is still no basis for claiming that Lerner's "math is wrong." As Lerner gave no math. As I explained, if one takes reasonable values (and I explained (*why* the numbers are reasonable) No, you did not. You merely repeated the claim. That's a lie. He never lies ;-) All the others are lying all the time: http://users.pandora.be/vdmoortel/di.../BoldFace.html http://users.pandora.be/vdmoortel/di...eliberate.html http://users.pandora.be/vdmoortel/di...s/YouLiar.html Dirk Vdm |
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Ned Wright's TBBNH Page (C)
Dirk Van de moortel wrote in message ... "Bjoern Feuerbacher" wrote in message ... greywolf42 wrote: [snip] There is still no basis for claiming that Lerner's "math is wrong." As Lerner gave no math. As I explained, if one takes reasonable values (and I explained (*why* the numbers are reasonable) No, you did not. You merely repeated the claim. That's a lie. He never lies ;-) All the others are lying all the time: http://users.pandora.be/vdmoortel/di.../BoldFace.html http://users.pandora.be/vdmoortel/di...eliberate.html http://users.pandora.be/vdmoortel/di...s/YouLiar.html Hello again, coward. Still no physics to post, Dinky? Still not willing to take those bets, Dinky? Bye-bye. greywolf42 ubi dubium ibi libertas |
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Ned Wright's TBBNH Page (C)
Bjoern Feuerbacher wrote in message ... greywolf42 wrote: Bjoern Feuerbacher wrote in message ... greywolf42 wrote: Bjoern Feuerbacher wrote in message ... greywolf42 wrote: [snip] Since Lerner did not identify what value he used for 'interesting mass,' the claim that his math was wrong is spurious. Well, it's rather clear (if one knows a bit about cosmology) what an "interesting mass" would be (several eV will do it). Hence the fact that Lerner doesn't give a specific value is rather irrelevant. It wasn't "clear" at all, in 1991. See report below. I read the report below and explained that it doesn't support your point - it only talks about *electron* neutrinos. Electron neutrinos are the masses we are discussing. We are discussing if 1991 it was known if neutrinos have an "cosmologically interesting" mass. Not only electron neutrinos. *All* neutrinos. Kamiokande only detects electron neutrinos. Right - and therefore, as Wright and me correctly point out, Kamiokande couldn't have rule out "cosmologically interesting" masses for the other two neutrinos. And -- as you have admitted before -- there was no reason in 1991 (either theoretical or experimental) to expect that mu and tau neutrinos were fundamentally more massive (or more 'interesting') than electron neutrinos. There is still no basis for claiming that Lerner's "math is wrong." As Lerner gave no math. As I explained, if one takes reasonable values (and I explained (*why* the numbers are reasonable) No, you did not. You merely repeated the claim. That's a lie. I gave you the formula with which one determines if a neutrino mass is cosmologically interesting or not (neutrino mass/92 eV/c^2). Using the formula, it turns out that 5eV/c^2 (the number Wright used) *is* a reasonable value. It is not a lie. You did not state why this equation that you pulled out of thin air gave you an 'interesting' mass. Nor did you indicate that this equation was derived or accepted prior to 1991. and puts them in, one sees that Lerner was wrong. Hence there are only two choices, IMO: 1) Lerner didn't do any math and made the whole thing up. 2) Lerner did some math and screwed it up. Ned Wright and me are only generous and assume that it was (2), not (1). Ah, the refuge of the true believer. The fallacy of the excluded middle, combined with a straw man. Care to come up with other possibilities, instead of simply asserting that there are others? Already given. And since you snipped them, I'll let you go hunting through prior threads. [snip] They appear to travel at the speed of light, so must have no mass. This argument doesn't make much sense. They *appear* to travel at the speed of light, so *must* have no mass? What a great logic! Well, yeah... if the 'appearance' is the result of an experimental measurement. Can you say 'arbitrarily close to?' No experiment can ever measure "arbitrarily close to", so this makes no sense at all. Bingo! Claiming evidence of mass when all we have is upper bounds is indeed senseless. What on earth are you talking about??? No one claimed that in 1991, we had evidence of mass; the only thing which was said is that with the numbers available in 1991 (for which I gave references!), a cosmoligically interesting mass could not be ruled out - contrary to Lerner's assertion. You contradict the reference I gave (1993, Lindley). And you continue to refuse to provide references of your own. Hint: we know today that neutrinos *have* mass, No, we see a discrepancy in theory. Pardon??? What on earth are you talking about??? Neutrino oscillations are clear evidence for neutrino masses. So where is "a discrepancy in theory"??? Neutrino 'oscillations'. They are postulated to explain a discrepancy between theory and observation. And we interpret this as 'evidence of mass.' Do you have another explanation for neutrino oscillations which fits all of the data? Neutrino oscillations ARE a theoretical explanation. Not data. However, this is still irrelevant to knowledge in 1991. I never claimed that it were relevant. Then don't waste everyone's time with irrelevant things. hence that they *don't* travel at the speed of light. Too bad that's what experiments show. The experiments show that they travel *approximately* at the speed of light. No experiment can ever show that they travel *exactly* at the speed of light. Hence the experiments which measure the velocities of neutrinos couldn't rule out a neutrino mass ever. They are the speed of light to at least 13 decimal places. As good as many of the best precisions in physics (and higher than that if you consider the inherent size of the supernova neutrino production burst). Therefore, obviously, the experiments which showed that they travel *approximately* at the speed of light weren't sensitive enough - and every experimental physicist should have known that even back then! ROTFLMAO! Rewrite the histories and the experiments, boys! Where on earth is your problem??? The supernova observations only showed that the mass of the electron neutrino must be smaller than 23eV/c^2. This obviously doesn't rule out a neutrino mass! What neutrino pulse width did you use to come up with that number? (I note you continue to evade giving actual references for your numbers.) We've found a discrepancy in our theory, so experiment must be in error. What discrepancy are you talking about??? And where did I say that an experiment is in error? I only pointed out that it wasn't *sensitive* enough! Neutrino oscillations point to neutrino masses around 10^(-3) eV/c^2; that the supernova measurements weren't sensitive enough to detect such a mass is a simple fact - So the accepted neutrino masses are a factor of 10,000 too small to be 'cosmologically interesting.' Why are you spending all that time arguing about 'smaller than 23 eV' if you know the answer is 10,000 times smaller? try reading the original papers! (see my references) *WHAT* references? *WHAT* original papers? I've been asking you to provide these for several rounds. Additionally, there are theories which predict not only the "light" neutrinos we know, but additional neutrinos which are much more heavy. Try reading up on "see-saw" mechanism. No. Please stick to the issue. Err, the issue is if the experiments back then were able to rule out heavy neutrinos or not. The "see-saw" mechanisms is another point that the experiments could *not* have rule this out. Hence this *is* the issue. Which leads us right back to that original issue, 'how heavy is heavy?' This wasn't the original issue. The original issue was "Were the supernova measurements sensitive enough to rule out a cosmologically interesting neutrino mass?", and the answer to this is no - see my references. No, the question was -- were neutrino masses too small to be 'cosmologically interesting.' If you and Ned agree about this, then the whole thing is a tempest in a teapot. [snip a bit] Today. Not in 1991. Absolutely wrong. It was clear even in 1991 that a mass of several eV would 1) give a substantial contribution to Omega and 2) could not be detected by the supernova measurements. Additionally, it was clear even in 1991 that the supernova measurements could give limits only on the electron neutrino mass, not on the masses of the other neutrinos. Ned Wright is right, and you are wrong. Live with it. LOL! Not according David Lindley (editor of Nature), as late as 1993. Merely repeating a claim never makes it true. I provided references and calculations. You ignored both so far. Hence it's you who is simply repeating a false claim, hoping that it will become true. Horsefeathers. You haven't provided a single reference. You have provided ZERO calculations. You provided one equation that you pulled out of thin air. [snip] They arrived in a 'bunch', (a period of 6 sec) after travelling 160,000 light years. And arrived minutes before the SN light pulse. So, they were travelling at around 0.999999999999875*c (according to Ned). Right. 0.999999999999875*c. Not c. That is c to 13 decimal places. How many decimal places do you want before you admit that it's 'c'? If neutrinos have a mass of around 10^(-3) eV/c^2, as the neutrino oscillation measurements imply, and an energy of 10 MeV, the travel at a speed of v/c = sqrt(1 - 10(-10)^2), which is approx. 1 - 0.5 * 10^(-20). So, in order to "see" the neutrino mass in experiments which measure their speed, you have to measure their speed with a sensitivity of 20 decimal places. Good luck. In other words, it's not 'c' until we exceed even the claimed precision of the most precise measurements made in physics. But, since you admit that neutrino masses are not 'cosmologically interesting', and since it was commonly accepted that neutrion mass was not 'cosmologically interesting' in 1991, there is no point to your continued argument..... So, again, where does Lerner get "they all travel at the speed of light" from? The only thing you can deduce from the supernova measurements is (taking Wright's numbers) that "they all travel at 0.999999999999875*c". And this doesn't help Lerner's case, because this still would give a significant contribution of the neutrino mass to Omega. You just keep asserting this, over and over. No, I gave you the formula which demonstrates this. I gave you references for the data and the formula. You ignored both so far. It's *YOU* who is asserting something over and over. A bold-faced lie. An equation out of thin air is not a reference. Please provide a pre-1991 reference for significant contribution to omega at this level. Already done. I gave two references (in another post on last friday) which, taken together, demonstrate the data from SN1987A give only an upper limit for the contribution of the electron neutrinos to Omega of 0.39. Obviously such a number *is* cosmologically interesting. A bold-faced lie. So, I'm going to snip the rest of this rant -- unless I spot an actual reference, someplace.... {snip} The measurements the article in Nature talk about are about beta decays. Surely you know that in beta decays, only electron neutrinos appear? This is the closest to a reference that you can come? An 'article in Nature'? LOL! {more snip} Where did you get the value, above? Try providing a reference from 1991. Already done in another post to this thread on Friday and (big surprise!) completely ignored by you. That post doesn't show on my newsreader. However, I did find it on Google. http://groups.google.com/groups?selm...z.uni-heidelbe rg.de The reference is to the well-known book by Kolb and Turner "The early universe", which was published in 1990 and includes lots of material which was known already long before. Why the need to try to 'extend' your arguments by implying it was known "long before?" If it was known "long before," please provide a reference from 'long before.' Both references were published at the end of 1990. The first paper (G.G.Raffelt) on 12/20/90. The second, "a well-known book on cosmology by two famous cosmologists" may not have been 'well known' in 1990. According to the preface, the first edition of TBBNH was published in "late 1990," a year and a half before the completion of the preface (written for a different publisher) in "May, 1992." So the first paper was undoubtedly published AFTER TBBNH was printed. Apologies for the confusion on publication date (the copyright is given as 1991). The month of the year did not matter, prior to your proffering of a December 1990 paper and a book published in 1990. {snip} The formula for the contribution of massive neutrinos to Omega does in no way at all depend on the assumption of the existence of dark matter. Only GR is used, plus some thermodynamics and a little Special Relativity (which must be used because the velocity of the neutrinos is so high). Try opening the book and looking at the calculation if you don't believe me. It's in chapter 5, the relevant formula I'm talking about is (5.33). Well, I'll give the book a try -- right after my next trip to the library. Until then, could you clarify the month of publication, in 1990? Thanks. {snip} greywolf42 ubi dubium ibi libertas |
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Ned Wright's TBBNH Page (C)
"Bjoern Feuerbacher" wrote in message ... greywolf42 wrote: [snip] Replacing the rest of the paragraph: ============================ Now, if Ned (in the year 2000) feels that neutrino mass is 'interesting' again, that's a valid point of discussion between theories -- if he can come up with a reference. However, it is NOT in any manner an 'error' on the part of Eric Lerner or TBBNH. I don't see why you have a problem that I snipped this. It has absolutely nothing to do with my point. It is smokescreen tactics. Didn't you know? It is meant to make you go away. Compare with #10 http://groups.google.com/groups?&as_...ing.google.com #9 http://groups.google.com/groups?&as_...upernews.co m #8 http://groups.google.com/groups?&as_...upernews.co m #7 http://groups.google.com/groups?&as_...upernews.co m #6 http://groups.google.com/groups?&as_...upernews.co m #5 http://groups.google.com/groups?&as_...upernews.co m #4 http://groups.google.com/groups?&as_...upernews.co m #3 http://groups.google.com/groups?&as_...upernews.co m #2 http://groups.google.com/groups?&as_...upernews.co m #1 http://groups.google.com/groups?&as_...upernews.co m Dirk Vdm |
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