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Natural Science Forum / Physics / General Physics / July 2008From dark matter to MOND
From dark matter to MOND http://arxiv.org/abs/0806.2585 Introductory remarks Modified Newtonian dynamics, or MOND, was proposed by Milgrom as an alternative to dark matter. Over the past 25 years a considerable lore has grown up around this idea, and now the very word seems to provoke strong reactions pro or con depending upon ones preconceptions or inclinations. Here I want to provide a minimalist definition of MOND a definition which is as free as possible from emotive charge of the idea; therefore, I will avoid terms like modified inertia or modified gravity. MOND is an algorithm that permits one to calculate the distribution of force in an object from the observed distribution of baryonic matter with only one additional fixed parameter having units of acceleration. This algorithm works very well on the scale of galaxies. The fact that it works is problematic for Cold Dark Matter (CDM), because this is not something that dark matter can naturally do. Moreover, MOND explains or subsumes systematic aspects of galaxy photometry and kinematics aspects which CDM does not address or gets wrong. Several of these systematics were not evident at the time that MOND was proposed, so this constitutes a predictive power going beyond the ability to explain observations a posteriori. I will present the evidence in favor of these assertions, so this will be a discussion primarily of the phenomenology. I will, however, draw the conclusion which to me is also minimal and quite obvious: standard CDM is falsified by the existence of this successful algorithm. More here: http://arxiv.org/abs/0806.2585 Surfer wrote on Sun, 29 Jun 2008 17:42:38 +0930: > From dark matter to MOND > http://arxiv.org/abs/0806.2585 [quoted text clipped - 29 lines] > More here: > http://arxiv.org/abs/0806.2585 Good link! Effectively, MOND is known to be more successfully than CDM, which cannot fit observed data so well as MOND does. Also all predictions by MOND have been verified in places where CDM has done none or wrong predictions. E.g. MOND predicted correct WMAP peaks when models using CDM failed [#]. Now the question is: what importance have the verified predictions and the matching to data for a community (relativists) who want GR to be valid elsewhere with independence that Nature is saying them? None. This is because them reject MOND and continue to search for dark matter [##]. [#] After the WMAP data was known relativists modified their models to fit the new data :-) [##] This is a similar situation when Newtonians never accepted that Newton theory could not explain Mercuty perihelion anomaly and searched for a new planet (Vulcan) which would explain the observed discrepancies.  SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org On Jun 29, 1:45 am, "Juan R." González-Álvarez <juanREM...@canonicalscience.com> wrote: > Surfer wrote on Sun, 29 Jun 2008 17:42:38 +0930: > [quoted text clipped - 36 lines] > Effectively, MOND is known to be more successfully than CDM, which cannot > fit observed data so well as MOND does. For what value of "known"? MOND can't replicate the observed CMBR power spectrum, explain the existence of the CMBR, replicate the observed ratios and distribution of light elements, or even get close to explaining the dynamics of colliding galaxies. > Also all predictions by MOND have been verified in places where CDM has > done none or wrong predictions. E.g. MOND predicted correct WMAP peaks > when models using CDM failed [#]. Wishful thinking. You have no literature references to back these / strong/ assertions up. > Now the question is: what importance have the verified predictions and > the matching to data for a community (relativists) who want GR to be > valid elsewhere with independence that Nature is saying them? What about galaxies that can only be explained by MOND under the insertion of what amounts to dark matter? Is that irony, or something different because MOND is doing it? > None. This is because them reject MOND and continue to search for dark > matter [##]. ...bullet cluster? Every time MOND comes under discussion, gravitational lensing is the elephant in the room that the MOND camp just /hates/ to discuss. Yea guys, you got a pretty good model for the dynamics of certain galaxies - good job. Too bad it is useless everywhere else. > [#] After the WMAP data was known relativists modified their models to > fit the new data :-) This is what is known as "lying". > [##] This is a similar situation when Newtonians never accepted that > Newton theory could not explain Mercuty perihelion anomaly and > searched for a new planet (Vulcan) which would explain the observed > discrepancies. This is known as being "stupid". Their method discovered Neptune and Pluto - and the discovery of Pluto postdates the successful explanation of Mercury's perihelion precession. The situation is not at all similar, and you know it. You are just being dishonest in the hope of if you ignore the evidence that disagrees with you, it will go away. > -- > Center for CANONICAL |SCIENCE) http://canonicalscience.org Eric Gisse wrote on Sun, 29 Jun 2008 07:55:32 -0700: (snip) SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org On Jun 30, 2:07 am, "Juan R." González-Álvarez <juanREM...@canonicalscience.com> wrote: > Eric Gisse wrote on Sun, 29 Jun 2008 07:55:32 -0700: > > (snip) > > -- > Center for CANONICAL |SCIENCE) http://canonicalscience.org Too difficult for you? > Eric Gisse wrote on Sun, 29 Jun 2008 07:55:32 -0700: > > (snip) MOND is Dead? ...most likely http://www.astro.ucla.edu/~wright/density.html#MOND http://www.astro.ucla.edu/~wright/old_new_cosmo.html 22 Oct 2002 - The Chandra X-ray Observatory presented evidence against the MOdification of Newtonian Dynamics (MOND) alternative to dark matter theories. The August 2002 Scientific American has a long article about MOND. The hot X-ray emitting gas around the galaxy NGC 720 forms an ellipsoidal cloud, which requires an ellipsoidal gravitational potential well. While an ellipsoidal cloud of dark matter could provide such a well, MOND would necessarily give a spherical potential well. In general MOND works well on the scale of individual galaxies, but not for clusters of galaxies. So why is MOND only maybe dead? Its supporters like Milgrom are persistent and clever, and they may come up with a MONDian explanation for NGC 720. More on Dark Matter http://www.astro.ucla.edu/~wright/cosmolog.htm#News 21 Aug 2006 - NASA announced updated information about the "bullet cluster" 1E0657-56 today. Two clusters of galaxies have recently collided in this X-ray source. This cluster is filled with hot gas so X-ray observations by the Chandra X-ray Observatory show where the ordinary matter is located. 90% of the ordinary matter (the "baryonic" matter) is hot gas. The new results [Clowe et al., Bradac et al.] use gravitational lensing of background galaxies to show where the sources of gravity are located. The sources of gravity in the cluster are not located where the ordinary matter is located, so this cluster is a counter-example to MOND. All of this was known in 2003 but with less precision. Sean Carroll has a nice post about this at Cosmic Variance. The Matter of the Bullet Cluster http://antwrp.gsfc.nasa.gov/apod/ap060824.html Explanation: The matter in galaxy cluster 1E 0657-56, fondly known as the "bullet cluster", is shown in this composite image. A mere 3.4 billion light-years away, the bullet cluster's individual galaxies are seen in the optical image data, but their total mass adds up to far less than the mass of the cluster's two clouds of hot x-ray emitting gas shown in red. Representing even more mass than the optical galaxies and x-ray gas combined, the blue hues show the distribution of dark matter in the cluster. Otherwise invisible to telescopic views, the dark matter was mapped by observations of gravitational lensing of background galaxies. In a text book example of a shock front, the bullet-shaped cloud of gas at the right was distorted during the titanic collision between two galaxy clusters that created the larger bullet cluster itself. But the dark matter present has not interacted with the cluster gas except by gravity. The clear separation of dark matter and gas clouds is considered direct evidence that dark matter exists. Sam Wormley wrote on Mon, 30 Jun 2008 17:00:03 +0000: > MOND is Dead? ...most likely > > http://www.astro.ucla.edu/~wright/density.html#MOND > http://www.astro.ucla.edu/~wright/old_new_cosmo.html (snip) Dark Matter is Dead (September 2007): http://www.skyatnightmagazine.com/viewIssue.asp?id=837 > More on Dark Matter > http://www.astro.ucla.edu/~wright/cosmolog.htm#News (snip) Do Dwarf Galaxies Favor MOND Over Dark Matter? (Apr. 2008): http://www.sciencedaily.com/releases/2008/04/080402202332.htm Seeing Through Dark Matter (Aug 2007): http://www.sciencemag.org/cgi/content/summary/317/5838/607 (\blockquote Dark matter was proposed to explain galaxy dynamics. A modification of Newton's law of gravitational force may offer a better explanation. ) See also http://arxiv.org/abs/astro-ph/0406673 http://arxiv.org/abs/astro-ph/0212293 http://arxiv.org/abs/astro-ph/0702146 http://arxiv.org/abs/astro-ph/0606216 http://arxiv.org/abs/astro-ph/0610298 http://arxiv.org/abs/astro-ph/0703590 http://arxiv.org/abs/0704.0381 http://arxiv.org/abs/0706.1279 http://arxiv.org/abs/astro-ph/0412614 http://arxiv.org/abs/astro-ph/0312570 http://arxiv.org/abs/astro-ph/0504130 http://arxiv.org/abs/0706.1775 http://arxiv.org/abs/hep-th/0703156 http://arxiv.org/abs/0711.0332 http://arxiv.org/abs/astro-ph/0504051 http://xxx.lanl.gov/abs/astro-ph/9801123 http://arxiv.org/abs/astro-ph/0703352 ... > The Matter of the Bullet Cluster > http://antwrp.gsfc.nasa.gov/apod/ap060824.html (snip) Several of above references explain why the NASA news about the bullet cluster result was premature. And why dark matter cannot explain velocity of the cluster but MOND can do it. SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org > Sam Wormley wrote on Mon, 30 Jun 2008 17:00:03 +0000: > [quoted text clipped - 21 lines] > > http://www.sciencemag.org/cgi/content/summary/317/5838/607 As I point out... oberservational evidence... pretty much rules out MOND. > (\blockquote > Dark matter was proposed to explain galaxy dynamics. A modification of [quoted text clipped - 48 lines] > cluster result was premature. And why dark matter cannot explain velocity > of the cluster but MOND can do it. Sam Wormley wrote on Mon, 30 Jun 2008 18:49:22 +0000: >> Sam Wormley wrote on Mon, 30 Jun 2008 17:00:03 +0000: >> [quoted text clipped - 24 lines] > As I point out... oberservational evidence... pretty much rules out > MOND. The article which you are replying (but you probably did not read) says the *contrary*, observational evidence pretty much rules out dark matter. (\blockquote Dark matter *was* proposed to explain galaxy dynamics. A modification of Newton's law of gravitational force [MOND] may offer a *better* explanation. ) See also large bunch of last evidence favoring MOND. >> http://arxiv.org/abs/astro-ph/0406673 >> [quoted text clipped - 40 lines] >> cluster result was premature. And why dark matter cannot explain >> velocity of the cluster but MOND can do it. SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org > Sam Wormley wrote on Mon, 30 Jun 2008 18:49:22 +0000: > >>> Sam Wormley wrote on Mon, 30 Jun 2008 17:00:03 +0000: >> As I point out... oberservational evidence... pretty much rules out >> MOND. [quoted text clipped - 7 lines] > explanation. > ) One observation supports MOND another contradicts MOND... You can't pick and choose. For MOND to be correct, it has to be correct all the time! Sam Wormley wrote on Tue, 01 Jul 2008 16:52:54 +0000: >> Sam Wormley wrote on Mon, 30 Jun 2008 18:49:22 +0000: >> [quoted text clipped - 16 lines] > pick and choose. For MOND to be correct, it has to be correct all > the time! i) You got it wrong regarding MOND (no observation contradicts MOND, read references provided) and ii) dark matter is not supported by observations (dark matter models also did several false predictions in places where MOND gave us the correct predictions, again read the references). SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org > Sam Wormley wrote on Tue, 01 Jul 2008 16:52:54 +0000: > [quoted text clipped - 26 lines] > several false predictions in places where MOND gave us the correct > predictions, again read the references). I think you should rethink your conclusions. Dark matter had a comon origin with real matter in the Big Bang. It comingles even today. The Earth Sun and stars are made mostly of it. > > Sam Wormley wrote on Tue, 01 Jul 2008 16:52:54 +0000: > [quoted text clipped - 28 lines] > > I think you should rethink your conclusions. I do too, but it is obvious he does not care what I think. He's unable to accept that maybe I have a good point, or at least argue against the points I make. Hell - there is another colliding cluster [MACS J0025.4-1222] that exhibits all the same features of the bullet cluster, except for the particular shape from the bow shock. arxiv gr:qc 0806.23201 covers it nicely. It turns out that - gee, imagine that - the CDM model explains the cluster nicely, while other models [MOND, TeVeS] still require dark matter to explain things. Its' funny when he tells us to read the literature when he hardly does so himself. He refused to comment on the specific points I raised - supported by quotes from the paper - regarding how supposedly CDM is falsified by the bullet cluster. Hell, I have just spent the last 3 hours reading up on cosmology papers from the June/July stuff on arXiv and I've learned some interesting things. Gotta burn the airplane time somehow. Sam Wormley wrote on Thu, 03 Jul 2008 01:23:16 +0000: >> i) >> You got it wrong regarding MOND (no observation contradicts MOND, read [quoted text clipped - 6 lines] >> > I think you should rethink your conclusions. If you have no time to read the dozens of references I provided in a previous posting at least take the time to read titles. You may find fine titles as: "Dark Matter is Dead", "Do Dwarf Galaxies Favor MOND Over Dark Matter?"... SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org On Jul 3, 4:36 am, "Juan R." González-Álvarez <juanREM...@canonicalscience.com> wrote: > Sam Wormley wrote on Thu, 03 Jul 2008 01:23:16 +0000: > [quoted text clipped - 16 lines] > -- > Center for CANONICAL |SCIENCE) http://canonicalscience.org The problems about DM universally revolve around numerical simulations. There are no major observational gaps like regarding MOND/ TeVeS and clusters. Sure you point me to the paper that supposedly refutes CDM using the bullet cluster, but then you ignore all the parts that make it verrrry speculative and not even remotely as cut and dry as you wish to believe. Yes, the CDM model appears to overpredict the number of dwarf & satellite galaxies. This is a problem of fine tuning which has some possible resolutions. It, however, is not of the same order-of- magnitude in "bad for theory" land as it is for MOND/TeVeS. It does amuse me slightly that you aren't even going off by the contents of the articles - just the titles. That is not science, nor is it even within sight of being objective. Eric Gisse wrote on Thu, 03 Jul 2008 21:09:36 -0700: > On Jul 3, 4:36 am, "Juan R." González-Álvarez > <juanREM...@canonicalscience.com> wrote: [quoted text clipped - 18 lines] >> -- >> Center for CANONICAL |SCIENCE) http://canonicalscience.org (snip many misunderstanding and usual /ad hominem/) SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org Not citing a Cahill paper? Good - you are branching out. [...] > I will present the evidence in favor of these assertions, so this will > be a discussion primarily of the phenomenology. I will, however, draw > the conclusion which to me is also minimal and quite obvious: standard > CDM is falsified by the existence of this successful algorithm. Certainly sets the tone for the paper. Claiming that DM is wrong because it has a simple model is extreme to the point of stupidity. Is nonrelativistic QM wrong because a schoolteacher in the late 1800's found a formula to explain the energy levels of hydrogen? No - only observations falsify a theory, not things like this. This is simply wishful thinking from someone who has his own idea of what the universe is like. I skimmed this paper because I'm pretty familiar with the observational evidence. Basically this is a quickie review of only the evidence in support of MOND. Though I find the absence of even a mention gravitational lensing evidence that supports dark matter rather interesting. Actually I find it very interesting - does the author simply not know about it, even though this paper was written a full two years after the discovery of the bullet cluster? Or does the author know about it and simply does not wish to discuss the matter since the lensing results laugh in the face of the arguments against DM? > More here:http://arxiv.org/abs/0806.2585 >Though I find the absence of even a mention gravitational lensing >evidence that supports dark matter rather interesting. Actually I find [quoted text clipped - 3 lines] >not wish to discuss the matter since the lensing results laugh in the >face of the arguments against DM? That is interesting, because he wrote here: "Gravitational lensing with modified gravity". http://www.iap.fr/col2007/talks/Tuesday/Sanders.ppt "Strong lensing always occurs in Newtonian regime." So I guess his position must be not that DM doesn't exist, but that for certain phenomena the DM explanations are not proving to be adequate and MOND explanations are better. Eg From: http://arxiv.org/abs/0806.2585 "Moreover, MOND explains or subsumes systematic aspects of galaxy photometry and kinematics aspects which CDM does not address or gets wrong." There is a comparison here of how Dark Matter and MOND fare in various observational tests. http://www.astro.umd.edu/~ssm/mond/mondvsDM.html Perhaps both are needed. Surfer wrote on Mon, 30 Jun 2008 13:39:07 +0930: > There is a comparison here of how Dark Matter and MOND fare in various > observational tests. > > http://www.astro.umd.edu/~ssm/mond/mondvsDM.html > > Perhaps both are needed. No really. MOND explains the data that DM does not or get wrong. Also, one may maintain in mind MOND is non-relativistic and cannot explain (really one would say "does not apply to") relativistic phenomena. This is task for relativistic-MOND. A proposal is TeVeS. It explain same data than MOND more relativistic data: GR, lensing, cluster, etc. I am not convinced that TeVeS was the adequate theory, but remember that GR was obtained after several years of unsuccessful tries, including the previous versions without the fundamental trace term. I wait one or two more version of relativistic MOND before having at hand a good version. SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org > On Sun, 29 Jun 2008 07:46:56 -0700 (PDT), Eric Gisse > [quoted text clipped - 12 lines] > "Gravitational lensing with modified gravity".http://www.iap.fr/col2007/talks/Tuesday/Sanders.ppt > "Strong lensing always occurs in “Newtonian” regime." I don't do powerpoint - got an actual PDF or web link? > So I guess his position must be not that DM doesn't exist, but that > for certain phenomena the DM explanations are not proving to be [quoted text clipped - 5 lines] > photometry and kinematics– aspects which CDM does not address or gets > wrong." Repeating the point doesn't make them true. All he does is repeat what is already known - that MOND handily explains things like the Tulley- Fisher relation. > There is a comparison here of how Dark Matter and MOND fare in various > observational tests. > > http://www.astro.umd.edu/~ssm/mond/mondvsDM.html Got anything with...say...REFERENCES? A score card by one of the primary investigators of MOND is hardly objective, especially with no literature references on things that MOND gets right or dark matter gets wrong. Hell, go anything more recent? The page has not been updated in years and does not even discuss recent lensing observations. I'm becoming tired of articles that "support" MOND which predate 2006 in either content or publishing date. > Perhaps both are needed. Worst of both worlds - good idea. Eric Gisse wrote on Mon, 30 Jun 2008 09:30:16 -0700: >> http://www.astro.umd.edu/~ssm/mond/mondvsDM.html > > Got anything with...say...REFERENCES? A score card by one of the primary > investigators of MOND is hardly objective, It is 10^99 times more objective and informed that your usual rambling against MOND. > especially with no literature > references on things that MOND gets right or dark matter gets wrong. Another lye. The author gives a hundred of references. (snip) SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org On Jun 30, 8:47 am, "Juan R." González-Álvarez <juanREM...@canonicalscience.com> wrote: > Eric Gisse wrote on Mon, 30 Jun 2008 09:30:16 -0700: > [quoted text clipped - 5 lines] > It is 10^99 times more objective and informed that your usual rambling > against MOND. You wouldn't know objectivity if it punched you in the balls. > > especially with no literature > > references on things that MOND gets right or dark matter gets wrong. > > Another lye. The author gives a hundred of references. Not for his little score card, and I'm not going to trawl through his page to find them. > (snip) > > -- > Center for CANONICAL |SCIENCE) http://canonicalscience.org Eric Gisse wrote on Mon, 30 Jun 2008 11:53:28 -0700: > On Jun 30, 8:47 am, "Juan R." González-Álvarez > <juanREM...@canonicalscience.com> wrote: [quoted text clipped - 9 lines] > > You wouldn't know objectivity if it punched you in the balls. Your objectivity is showed below. >> > especially with no literature >> > references on things that MOND gets right or dark matter gets wrong. [quoted text clipped - 3 lines] > Not for his little score card, and I'm not going to trawl through his > page to find them. This is a very objective and fair attitude. SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org On Jul 1, 1:43 am, "Juan R." González-Álvarez <juanREM...@canonicalscience.com> wrote: > Eric Gisse wrote on Mon, 30 Jun 2008 11:53:28 -0700: > [quoted text clipped - 26 lines] > -- > Center for CANONICAL |SCIENCE) http://canonicalscience.org I never ever claimed to be objective. You aren't objective either - which somewhat taints the accusation. Eric Gisse wrote on Tue, 01 Jul 2008 09:15:08 -0700: > On Jul 1, 1:43 am, "Juan R." González-Álvarez > <juanREM...@canonicalscience.com> wrote: [quoted text clipped - 31 lines] > > I never ever claimed to be objective. Then both agree that your unfounded accusation was not objective, which *was* my point. (\blockquote A score card by one of the primary investigators of MOND is hardly objective ) SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org On Jul 2, 1:28 am, "Juan R." González-Álvarez <juanREM...@canonicalscience.com> wrote: > Eric Gisse wrote on Tue, 01 Jul 2008 09:15:08 -0700: > [quoted text clipped - 36 lines] > Then both agree that your unfounded accusation was not objective, which > *was* my point. The accusation rings hollow when you are guilty of being just as not- objective as me. I simply realize it, and you don't. > (\blockquote > A score card by one of the primary investigators of MOND is hardly [quoted text clipped - 3 lines] > -- > Center for CANONICAL |SCIENCE) http://canonicalscience.org Eric Gisse wrote on Wed, 02 Jul 2008 10:31:06 -0700: > On Jul 2, 1:28 am, "Juan R." González-Álvarez > <juanREM...@canonicalscience.com> wrote: [quoted text clipped - 38 lines] >> Then both agree that your unfounded accusation was not objective, which >> *was* my point. (snip) >> (\blockquote >> A score card by one of the primary investigators of MOND is hardly [quoted text clipped - 3 lines] >> -- >> Center for CANONICAL |SCIENCE) http://canonicalscience.org SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org >> On Sun, 29 Jun 2008 07:46:56 -0700 (PDT), Eric Gisse >> [quoted text clipped - 14 lines] > >I don't do powerpoint - got an actual PDF or web link? The author is different, but there is a section on gravitational lensing in here: Modified Newtonian Dynamics, an Introductory Review http://arxiv.org/abs/astro-ph/0601478 > On Mon, 30 Jun 2008 09:30:16 -0700 (PDT), Eric Gisse > [quoted text clipped - 22 lines] > > Modified Newtonian Dynamics, an Introductory Reviewhttp://arxiv.org/abs/astro-ph/0601478 ....again, predates the bullet cluster. Uninteresting. >>>> That is interesting, because he wrote here: >>>> "Gravitational lensing with modified gravity".http://www.iap.fr/col2007/talks/Tuesday/Sanders.ppt >>>> "Strong lensing always occurs in “Newtonian” regime." >>> I don't do powerpoint - got an actual PDF or web link? "I don't do powerpoint", dude, even OpenOffice does Powerpoint. Download it someday. It's available for *all* platforms. >> The author is different, but there is a section on gravitational >> lensing in here: >> >> Modified Newtonian Dynamics, an Introductory Reviewhttp://arxiv.org/abs/astro-ph/0601478 > > ....again, predates the bullet cluster. Uninteresting. And most of the articles that do talk about the Bullet Cluster seem to predate the Abell 520 Cluster. At least it seems like they must predate Abell 520, since so few have any mention of it. It's funny, but I thought Abell 520 was discovered only a year after the Bullet, but I guess it takes several years to get these tests done, and articles written about it, etc. Here's an early article about the Bullet, Aug 21, 2006: SPACE.com -- Colossal Cosmic Collision Reveals Mysterious Dark Matter http://www.space.com/scienceastronomy/060821_dark_matter.html And here's an article about Abell 520, Aug 17, 2007: SPACE.com -- New Mystery of Invisible Matter Generated by Cosmic Collision http://www.space.com/scienceastronomy/070817_dm_mystery.html Abell 520 cluster shows Dark Matter in places where there aren't even any galaxies, and then where there are galaxies, some of them don't even have any Dark Matter around them! Tsk, tsk, how inconvenient that must be?! ;-) Yousuf Khan [...] Yea, most DM articles aren't going to mention Abell 520 - and why would they? Nothing conclusive can be derived from the cluster, other than "we need to think about this more". On the other hand, any article about MOND that tries to evangelize the theory and vilify DM that /does not mention/ DM is automagically suspect and most likely crap. Ditto for any person who does the same. The analogy "Abell 520 is to DM as the bullet cluster is to MOND" is utterly invalid. > And here's an article about Abell 520, Aug 17, 2007: > SPACE.com -- New Mystery of Invisible Matter Generated by Cosmic Collisionhttp://www.space.com/scienceastronomy/070817_dm_mystery.html Anything past the original Space and the original article in the arXiv? > Abell 520 cluster shows Dark Matter in places where there aren't even > any galaxies, and then where there are galaxies, some of them don't even > have any Dark Matter around them! Tsk, tsk, how inconvenient that must > be?! ;-) > > Yousuf Khan How exactly is Abell 520 something that conclusively blows dark matter out of the water? Lensing observations that directly map mass have ruled out MOND, though that hasn't stopped the MOND/TeVeS crew from claiming they "can" explain everything. All I see is something that raises interesting questions. I'd like to know how the DM got dropped in the center - was it some lucky gravitational coincidence, was it a collision between a regular galaxy and a product of a previous collision that had no dark matter? Something else? What I don't see is something that /anyone/ can smugly point to and say 'ha ha, your theory is dead'. Though it gives me a perverse sense of amusement to see the occasional article that takes a crack at using MOND, and then comes up with / reducing/ the amount of DM needed so you need MOND *and* DM - worst of both worlds. As far as using a particular theory to explain individual galactic dynamics is concerned, MOND is the clear winner regardless of who is right. You don't need a supercomputer to apply MOND, however you _do_ need one to do the particle simulations for dark matter. Which is then dependent on the assumptions used for DM, etc. So claims of success about the dynamics of individual galaxies are interesting but not something I regard with a large amount of merit. On the other hand I find it very interesting that while MOND cannot even remotely explain the observed big bang power spectrum, folks still treat MOND as viable. Or even TeVeS as viable! How did it get to the point where a theory with a half dozen extra arbitrary degrees of freedom is more palatable than the concept of matter that's electromagnetically neutral? > [...] > > Yea, most DM articles aren't going to mention Abell 520 - and why > would they? Nothing conclusive can be derived from the cluster, other > than "we need to think about this more". ROFL! Yeah, I'd say they need to think about this some more. I couldn't have said it better. > On the other hand, any article about MOND that tries to evangelize the > theory and vilify DM that /does not mention/ DM is automagically > suspect and most likely crap. Ditto for any person who does the same. > The analogy "Abell 520 is to DM as the bullet cluster is to MOND" is > utterly invalid. Really, so you're telling me that it's not just a teensy bit disturbing that the supposed dark matter doesn't even correspond to galaxies in this cluster? The dark matter is not only in places where there are no galaxies, but it's also *not* in places where there are galaxies. I thought DM was only supposed to exist in galaxies? That would be my first clue that perhaps the lensing effect is due to something other than DM and/or gravity in general. > How exactly is Abell 520 something that conclusively blows dark matter > out of the water? Lensing observations that directly map mass have > ruled out MOND, though that hasn't stopped the MOND/TeVeS crew from > claiming they "can" explain everything. There's no proof the lensing effect is due to mass or gravity. To me, the lensing effect looks very much like the lensing effect of shimmering water. Certain new quantum-gravity theories are looking at space-time not as a continuum, but as discrete atoms. If space-time is atomic, then it can be fluidic. A fluidic space-time could fluctuate in a way that will shimmer and create lensing effects. MOND and TeVeS could simply be the initial numerical approximations of the deeper fluidic reality. > As far as using a particular theory to explain individual galactic > dynamics is concerned, MOND is the clear winner regardless of who is [quoted text clipped - 3 lines] > about the dynamics of individual galaxies are interesting but not > something I regard with a large amount of merit. Something to be said for calculations that don't require a supercomputer. Engineers have been using approximate calculations to build upto your modern lifestyle long before there were supercomputers or even full explanations of those phenomenon. Yousuf Khan YKhan wrote on Wed, 02 Jul 2008 01:29:54 -0700: > There's no proof the lensing effect is due to mass or gravity. To me, > the lensing effect looks very much like the lensing effect of shimmering [quoted text clipped - 3 lines] > will shimmer and create lensing effects. MOND and TeVeS could simply be > the initial numerical approximations of the deeper fluidic reality. Both MOND and TeVeS are being derived from several fundamental theories. For instance, in one of prepints I cited in a previous message TeVeS is obtained from string theory, and since MOND can be obtained from TeVeS, therefore MOND would receive a string theory foundation. Personally I would prefer another foundation for MOND, but the idea that MOND is just "curve fitting" is another myth promoted by CDM fans. SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org On Jul 2, 11:25 am, "Juan R." González-Álvarez <juanREM...@canonicalscience.com> wrote: > YKhan wrote on Wed, 02 Jul 2008 01:29:54 -0700: > [quoted text clipped - 13 lines] > Personally I would prefer another foundation for MOND, but the idea that > MOND is just "curve fitting" is another myth promoted by CDM fans. Certainly ironic if CDM fans claim to not like empiricism or curve- fitting.. how do they place the CDM? On Jul 2, 4:01 am, luke.s...@space.unibe.ch wrote: > On Jul 2, 11:25 am, "Juan R." González-Álvarez > [quoted text clipped - 19 lines] > Certainly ironic if CDM fans claim to not like empiricism or curve- > fitting.. how do they place the CDM? Still curve fitting, just that its' backed with a shade more observational evidence. luke.saul wrote on Wed, 02 Jul 2008 05:01:05 -0700: > On Jul 2, 11:25 am, "Juan R." González-Álvarez > <juanREM...@canonicalscience.com> wrote: [quoted text clipped - 20 lines] > Certainly ironic if CDM fans claim to not like empiricism or curve- > fitting.. how do they place the CDM? Ironic maybe, unfair sure. The big advantage of MOND is that is a *predictive* theory. Its predictions have been verified. Milgrom did several when started MOND and were verified. CDM has done no real prediction, and in some cases did wrong ones. CDM is an exercise on data fitting a /posteriori/. SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org On Jul 2, 1:25 am, "Juan R." González-Álvarez <juanREM...@canonicalscience.com> wrote: > YKhan wrote on Wed, 02 Jul 2008 01:29:54 -0700: > [quoted text clipped - 13 lines] > Personally I would prefer another foundation for MOND, but the idea that > MOND is just "curve fitting" is another myth promoted by CDM fans. Then what's with that arbitrary function in MOND, and the arbitrary scalar & vector fields in TeVeS? > -- > Center for CANONICAL |SCIENCE) http://canonicalscience.org Eric Gisse wrote on Wed, 02 Jul 2008 10:47:06 -0700: > On Jul 2, 1:25 am, "Juan R." González-Álvarez > <juanREM...@canonicalscience.com> wrote: [quoted text clipped - 17 lines] >> Personally I would prefer another foundation for MOND, but the idea >> that MOND is just "curve fitting" is another myth promoted by CDM fans. (snip) SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org On Jul 2, 5:25 am, "Juan R." González-Álvarez <juanREM...@canonicalscience.com> wrote: > Both MOND and TeVeS are being derived from several fundamental theories. > For instance, in one of prepints I cited in a previous message TeVeS is > obtained from string theory, and since MOND can be obtained from TeVeS, > therefore MOND would receive a string theory foundation. Well, if Teves comes from Strings then it would be the first really useful thing that Strings will have derived. Finally make it something other than a sci-fi theory. > Personally I would prefer another foundation for MOND, but the idea that > MOND is just "curve fitting" is another myth promoted by CDM fans. MOND and Teves aren't the only theories on the block. John Moffat has another theory called MOG. I don't know if its derived from MOND, but I suspect that it predates MOND. "Previous studies suggested that the Bullet Cluster clearly demonstrates the presence of dark matter. But when Brownstein and Moffat compared the observed gravitational lensing and distribution of gas with that predicted using MOG theory, they found no evidence for this. In other words, it is more natural to explain the appearance of this cluster using a revised theory of gravitation than by including dark matter. MOG theory emerges from a generalization of relativity that eluded even Einstein, has been developed by Moffat for nearly thirty years and is now yielding astronomical and cosmological results. The theory has been used to successfully explain the movement of stars in over 100 galaxies and the motion of galaxies in more than 100 clusters. MOG theory may also explain the apparent anomalous deceleration of the Pioneer 10 and 11 space probes, launched in the early 1970s and now more than 12000 million km from the Sun. " http://www.physorg.com/news113031879.html [...] Physics by press release is unacceptable. It didn't work for cold fusion, it isn't working for string theory, and by god it will /not/ work for Moffat and his pet theory. Fortunately, arXiv is riddled with papers from him so there is something to actually go on. His theory is, from what I can see, a whole lot like TeVeS. He has the tensor field from the Einstein-Hilbert action along with the contributions from a vector and not just one - not two - but _THREE_ scalar fields. Lest I confuse anyone, my complaint with TeVeS [and MOG] is roughly similar to that of string theory. With an arbitrarily large set of free parameters you can predict anything you want. Not to detract too much from any successful predictions, but the complaint that dark matter/energy is "wrong" or whatever because it is silly that invisible matter and energy are assumed rings rather hollow. Especially when the primary competing theories have an increasingly large number of free parameters. MOND has its' free interpolative function while doing a good job in a surprising set of circumstances, fails miserably elsewhere. TeVeS has 5 extra degrees of freedom in addition to the ten from the tensor field, subject to whatever apparently weak constraints that the field equations impose. MOG has two more degrees of freedom when compared to TeVeS from two extra scalar fields which gives it *17* degrees of freedom to explain and postdict. Is it just me or have the people who are trying to explain away dark matter and dark energy getting caught up in exactly what they are deriding? > Physics by press release is unacceptable. It didn't work for cold > fusion, it isn't working for string theory, and by god it will /not/ > work for Moffat and his pet theory. Then, why did it work for you when the press proclaimed Einstein the nitwit, the plagiarist, and the liar as the messiah to the unified religion of SR and GR? > His theory is, from what I can see, a whole lot like TeVeS. He has the > tensor field from the Einstein-Hilbert action along with the > contributions from a vector and not just one - not two - but _THREE_ > scalar fields. Since GR is based on man-made mathematical gages to decide how much space or spacetime is curved, it is utterly absurd for anther conjecture to do the same. <shrug> > Lest I confuse anyone, my complaint with TeVeS [and MOG] is roughly > similar to that of string theory. Your assessment is not even close. <shrug> > With an arbitrarily large set of > free parameters you can predict anything you want. Not to detract too > much from any successful predictions, but the complaint that dark > matter/energy is "wrong" or whatever because it is silly that > invisible matter and energy are assumed rings rather hollow. Well, GR is based on very faulty mathematical foundation. GR can only be wrong. Any conjectures based on GR or its faulty mathematical foundation can only be wrong as well. Correct me if I am wrong. This is called logical thinking. > Especially when the primary competing theories have an increasingly > large number of free parameters. [...] Oh, boy. We have someone who has been a multi-year super senior struggling to get his BA/BS degree talking like a true expert. > Is it just me or have the people who are trying to explain away dark > matter and dark energy getting caught up in exactly what they are > deriding? Just you the multi-year super senior. | > Physics by press release is unacceptable. It didn't work for cold | > fusion, it isn't working for string theory, and by god it will /not/ [quoted text clipped - 3 lines] | nitwit, the plagiarist, and the liar as the messiah to the unified | religion of SR and GR? Because accepting aether leads to stupidity. Yours. <shrug> > | > Physics by press release is unacceptable. It didn't work for cold > | > fusion, it isn't working for string theory, and by god it will /not/ [quoted text clipped - 5 lines] > > Because accepting aether leads to stupidity. Yours. <shrug> This statement is utterly false. <shrug> Denying the Aether is accepting Voodooism in physics. After all, it has been observed how light propagates for several hundred years already. Have you been hiding under a rock some where in England? | > | > Physics by press release is unacceptable. It didn't work for cold | > | > fusion, it isn't working for string theory, and by god it will /not/ [quoted text clipped - 9 lines] | | Denying the Aether is accepting Voodooism in physics. You are a nitwit, a plagiarist, and a liar. <shrug (plagiarised)> | After all, it | has been observed how light propagates for several hundred years | already. Have you been hiding under a rock some where in England? Accepting aether is accepting voodooism in technology. After all, it has been observed that ring laser gyroscopes work and would not do so if your stupid aether were present. <shrug (plagiarised)> Therefore for someone that can understand GPS but cannot understand how another piece of common technology works you have to be utterly stupid, a pig-headed nitwit just like Roberts. <shrug (plagiarised)> After all, it has been observed how light propagates for several hundred years already and there is no aether. <shrug (plagiarised)> Rather than hiding under a rock, you have your stupid head up your arse just like Roberts and refuse to recognise Sagnac, you f.cking ignorant nitwit shaman. <shrug (plagiarised)> http://www.androcles01.pwp.blueyonder.co.uk/Sagnac/Sagnac.htm http://www.androcles01.pwp.blueyonder.co.uk/Sagnac/SagnacIdiocy.htm > "Koobee Wublee" <koobee.wub...@gmail.com> wrote in message > | Denying the Aether is accepting Voodooism in physics. > > You are a nitwit, a plagiarist, and a liar. <shrug (plagiarised)> Your accusation is cheap. <shrug> > | After all, it > | has been observed how light propagates for several hundred years > | already. Have you been hiding under a rock some where in England? > > Accepting aether is accepting voodooism in technology. Well, that is how the mathematics of electromagnetism tells you. <shrug> > After all, > it has been observed that ring laser gyroscopes work and would > not do so if your stupid aether were present. <shrug (plagiarised)> So, you do not understand how the Aether would behave even with all these textbooks explaining how electromagnetism works. <shrug> > Therefore for someone that can understand GPS but cannot understand > how another piece of common technology works you have to be > utterly stupid, a pig-headed nitwit just like Roberts. <shrug (plagiarised)> You are ranting now. <shrug> > After all, it has been observed how light propagates for several hundred > years already and there is no aether. <shrug (plagiarised)> You are merely ignorant. <shrug> > Rather than hiding under a rock, you have your stupid head up your arse > just like Roberts and refuse to recognise Sagnac, you f.cking ignorant > nitwit shaman. <shrug (plagiarised)> How is that possible? You are utterly delusional in your ignorance. <shrug> > http://www.androcles01.pwp.blueyonder.co.uk/Sagnac/Sagnac.htm > http://www.androcles01.pwp.blueyonder.co.uk/Sagnac/SagnacIdiocy.htm Androcles’ website is mostly junk except my GPS write-up. <shrug> On Jul 4, 12:43 am, "Androcles" wrote: > "Koobee Wublee" <koobee.wub...@gmail.com> wrote in message > | Denying the Aether is accepting Voodooism in physics. > > You are a nitwit, a plagiarist, and a liar. <shrug (plagiarised)> Your accusation is cheap. <shrug> ========================= Yes, as you should know. <shrug> > | After all, it > | has been observed how light propagates for several hundred years > | already. Have you been hiding under a rock some where in England? > > Accepting aether is accepting voodooism in technology. Well, that is how the mathematics of electromagnetism tells you. <shrug> ----------------------------------------------------------------------------- Liar. Faraday's E = -dB/dt doesn't say anything about aether. Shrug that up your arse. ------------------------------------------------------------------------------ > After all, > it has been observed that ring laser gyroscopes work and would > not do so if your stupid aether were present. <shrug (plagiarised)> So, you do not understand how the Aether would behave even with all these textbooks explaining how electromagnetism works. <shrug> ============================================== So you a nitwit that plagiarises text books. <shrug> > Therefore for someone that can understand GPS but cannot understand > how another piece of common technology works you have to be > utterly stupid, a pig-headed nitwit just like Roberts. <shrug > (plagiarised)> You are ranting now. <shrug> =========================================== So you are a liar. <shrug> > After all, it has been observed how light propagates for several hundred > years already and there is no aether. <shrug (plagiarised)> You are merely ignorant. <shrug> =========================== You are merely a nitwit, a plagiarist, and a liar. <shrug> > Rather than hiding under a rock, you have your stupid head up your arse > just like Roberts and refuse to recognise Sagnac, you f.cking ignorant > nitwit shaman. <shrug (plagiarised)> How is that possible? ================ You tell me, you can only hand-wave as you refuse to accept the evidence. <shrug> ======================================= You are utterly delusional in your ignorance. <shrug> ===================================== You are utterly a fuckheaded nitwit, a plagiarist, and a liar. <shrug> > http://www.androcles01.pwp.blueyonder.co.uk/Sagnac/Sagnac.htm > http://www.androcles01.pwp.blueyonder.co.uk/Sagnac/SagnacIdiocy.htm Androcles’ website is mostly junk except my GPS write-up. <shrug> ===================================== Oh... you mean where you wrote "Androcles is correct" before you became a fuckheaded nitwit? > > Physics by press release is unacceptable. It didn't work for cold > > fusion, it isn't working for string theory, and by god it will /not/ [quoted text clipped - 3 lines] > nitwit, the plagiarist, and the liar as the messiah to the unified > religion of SR and GR? I imagine you get a certain gleam in your eye when you start to rant about Einstein, complete with a little bit of saliva gathering in the corner of your mouth. Doesn't Einstein make you MAD? All that fame and admiration for a man whose been dead for a half century now, and not a little bit of attention for poor little kooby. > > His theory is, from what I can see, a whole lot like TeVeS. He has the > > tensor field from the Einstein-Hilbert action along with the [quoted text clipped - 4 lines] > space or spacetime is curved, it is utterly absurd for anther > conjecture to do the same. <shrug> A little ignorance [GR is not based on 'gages'] combined with a whole lot of arrogance does not an argument make. YOU might not think curvature is valid in any meaningful sense, but that isn't for you to decide. > > Lest I confuse anyone, my complaint with TeVeS [and MOG] is roughly > > similar to that of string theory. > > Your assessment is not even close. <shrug> Why even respond to me then? You apparently think you know my thinking process better than I do. You can carry on the entire conversation in your head, without having to post to this newsgroup! > > With an arbitrarily large set of > > free parameters you can predict anything you want. Not to detract too [quoted text clipped - 6 lines] > foundation can only be wrong as well. Correct me if I am wrong. This > is called logical thinking. GR is based on Lagrangian mechanics and Riemannian geometry. Since you understand neither of the subjects, what's the point of correcting you? You can't even prove that the surface area of a sphere in Euclidean geometry is 4 pi r^2 and you have the stones to rant endlessly about general relativity! > > Especially when the primary competing theories have an increasingly > > large number of free parameters. [...] > > Oh, boy. We have someone who has been a multi-year super senior > struggling to get his BA/BS degree talking like a true expert. Keep on firing the scattershot - you'll hit a target eventually. Try not to knock the education of someone who knows more than you regarding a subject you've spent years arguing about. > > Is it just me or have the people who are trying to explain away dark > > matter and dark energy getting caught up in exactly what they are > > deriding? > > Just you the multi-year super senior. When did you get _your_ degree in physics? Oh that's right - you didn't. > > Then, why did it work for you when the press proclaimed Einstein the > > nitwit, the plagiarist, and the liar as the messiah to the unified [quoted text clipped - 3 lines] > about Einstein, complete with a little bit of saliva gathering in the > corner of your mouth. Your imagination remains your imagination. <shrug> Einstein was a nitwit, a plagiarist, and a liar. There is nothing that I can gain from Einstein the nitwit, the plagiarist, and the liar. <shrug> > Doesn't Einstein make you MAD? No. <shrug> > All that fame and admiration for a man > whose been dead for a half century now, and not a little bit of > attention for poor little kooby. Well, there is nothing to capitalize on Einstein the nitwit, the plagiarist, and the liar. <shrug> > > Since GR is based on man-made mathematical gages to decide how much > > space or spacetime is curved, it is utterly absurd for anther [quoted text clipped - 4 lines] > curvature is valid in any meaningful sense, but that isn't for you to > decide. Yes, the group decision is laughable. <shrug> > > Your assessment is not even close. <shrug> > > Why even respond to me then? You apparently think you know my thinking > process better than I do. You can carry on the entire conversation in > your head, without having to post to this newsgroup! Hey, this is a public newsgroup discussion, is it not? Why are you so devastated? You must be taking this very personally. <shrug> You need to concentrating on getting your degree first before you can criticizing others. > > Well, GR is based on very faulty mathematical foundation. GR can only > > be wrong. Any conjectures based on GR or its faulty mathematical > > foundation can only be wrong as well. Correct me if I am wrong. This > > is called logical thinking. > > GR is based on Lagrangian mechanics and Riemannian geometry. Yes, GR is based on Riemannian geometry, but it is mis-applied. Let’s try this again. The geometry must be invariant. To describe the invariant geometry, the metric must vary with the choice of coordinate system. Thus, the metric cannot be a tensor. If you call the geodesic equations as part of GR, then yes part of GR is based on the Lagrangian method. However, since geodesic equations preceded GR by many decades, I would not claim the geodesic equations as part of GR. GR is only limited to the field equations. > Since you > understand neither of the subjects, what's the point of correcting > you? Your accusation is cheap. <shrug> > You can't even prove that the surface area of a sphere in Euclidean > geometry is 4 pi r^2 and you have the stones to rant endlessly about > general relativity! Yes, I did. You just do not understand the answer. <shrug> > > Oh, boy. We have someone who has been a multi-year super senior > > struggling to get his BA/BS degree talking like a true expert. > > Keep on firing the scattershot - you'll hit a target eventually. Did I say something wrong? Are you not a multi-year super senior without a BA/BS degree still? > Try not to knock the education of someone who knows more than you > regarding a subject you've spent years arguing about. Daydreaming about disposing your opponent is sometimes very healthy fro your mind especially after your *ss has been kicked so badly by your opponent. <shrug> > > Just you the multi-year super senior. > > When did you get _your_ degree in physics? Oh that's right - you > didn't. Keep guessing. Are you helping Professor Draper to find out which university gave me all these degrees? I would very much to be there when you guys register a complaint about that institution awarding me these degrees. Don’t forget to tell them that you got your *sses kicked so badly in these newsgroup discussions that you are supposed to know the subjects well. Ahahahaha... > > > Then, why did it work for you when the press proclaimed Einstein the > > > nitwit, the plagiarist, and the liar as the messiah to the unified [quoted text clipped - 5 lines] > > Your imagination remains your imagination. <shrug> Because if it weren't, it wouldn't be. > Einstein was a nitwit, a plagiarist, and a liar. There is nothing > that I can gain from Einstein the nitwit, the plagiarist, and the > liar. <shrug> Other than as a platform to being relevant - even if it is in a small recess of the internet that only laughs at you when it isn't ignoring you. Still that's more attention than you usually get - do your children or grandchildren ever call you anymore? > > Doesn't Einstein make you MAD? > > No. <shrug> Oh, so you have *no* emotional investment in Einstein? Even though you have spent several years defaming and generally lying your a.s off about him personally and professionally? I think people who act like that are called sociopaths. The choices here are "sociopath" or "liar". Which are you? > > All that fame and admiration for a man > > whose been dead for a half century now, and not a little bit of > > attention for poor little kooby. > > Well, there is nothing to capitalize on Einstein the nitwit, the > plagiarist, and the liar. <shrug> Other than the attention you get by making the claims. > > > Since GR is based on man-made mathematical gages to decide how much > > > space or spacetime is curved, it is utterly absurd for anther [quoted text clipped - 6 lines] > > Yes, the group decision is laughable. <shrug> Again - who are you to make that call? You are unable to demonstrate competence in the tools you criticize. > > > Your assessment is not even close. <shrug> > [quoted text clipped - 4 lines] > Hey, this is a public newsgroup discussion, is it not? Why are you so > devastated? You must be taking this very personally. <shrug> I'm more devastated that my cheap gungzhao chinese sh.t fireworks don't work worth a damn. I'm sure the roll of black cats will make up the difference though! Actually I'm more devastated that my legs are covered in mosquito bites. Little f.ckers are out for blood tonight. > You need to concentrating on getting your degree first before you can > criticizing others. Multitasking, kooby! Multitasking! Not just a feature of a modern operating system anymore! > > > Well, GR is based on very faulty mathematical foundation. GR can only > > > be wrong. Any conjectures based on GR or its faulty mathematical [quoted text clipped - 7 lines] > invariant geometry, the metric must vary with the choice of coordinate > system. Thus, the metric cannot be a tensor. How do you expect an actual discussion of the subject in question when you can't even use the terms right despite several years of corrections? The phrase "the geometry must be invariant" has no meaning to anyone but yourself and those who have the kooby<-->GR dictionary. Your whining touches on a larger scale of ignorance than you have yet mentioned. Evaluate the good ol' metric tensor in Euclidean geometry for Cartesian and then spherical coordinates. What's the difference? NOTHING. You haven't managed to explain your way past that simple SIMPLE example since I started bringing it up in when...2006? > If you call the geodesic equations as part of GR, then yes part of GR > is based on the Lagrangian method. However, since geodesic equations > preceded GR by many decades, I would not claim the geodesic equations > as part of GR. GR is only limited to the field equations. So you think GR isn't related to Riemannian geometry even though the Einstein-Hilbert action is proportional to the Ricci scalar? Or do you still reject the Einstein-Hilbert action on some arbitrary and capricious basis as per usual? > > Since you > > understand neither of the subjects, what's the point of correcting > > you? > > Your accusation is cheap. <shrug> Then prove me wrong. Again - the Euclidean metric in spherical coordinates is ds^2 = dr^2 + r^2 [d\theta^2 + sin(\theta)^2 d\phi^2]. Prove that the surface area of a sphere in this specific metric is 4 pi r^2. Its' like 8 lines of math, why are you afraid of proving me wrong with 8 lines of near- trivial calculus? > > You can't even prove that the surface area of a sphere in Euclidean > > geometry is 4 pi r^2 and you have the stones to rant endlessly about > > general relativity! > > Yes, I did. You just do not understand the answer. <shrug> No, you didn't - you simply _wrote the answer_. You are not able to fill in the steps between writing the Euclidean metric in spherical coordinates and writing "the surface area of a sphere is 4 pi r^2". Since you like to harp on me being in school, I'll relay a relevant example. If you are assigned a problem and you simply write down what you think the answer is, you will get zero points whether it is right or not. > > > Oh, boy. We have someone who has been a multi-year super senior > > > struggling to get his BA/BS degree talking like a true expert. [quoted text clipped - 3 lines] > Did I say something wrong? Are you not a multi-year super senior > without a BA/BS degree still? Keep on firing, kooby. I'll discuss my personal life with you when you stop posting under a pseudonym and join in the discussion under equal terms. > > Try not to knock the education of someone who knows more than you > > regarding a subject you've spent years arguing about. > > Daydreaming about disposing your opponent is sometimes very healthy > fro your mind especially after your *ss has been kicked so badly by > your opponent. <shrug> You are hallucinating. I blame whatever drugs you are on. > > > Just you the multi-year super senior. > [quoted text clipped - 7 lines] > kicked so badly in these newsgroup discussions that you are supposed > to know the subjects well. Ahahahaha... Whether or not you actually have them is irrelevant at this point because you do not have access to that knowledge. You are unable to display competence in even basic calculus, much less the complicated subjects you routinely rant about. > > Your imagination remains your imagination. <shrug> > > Because if it weren't, it wouldn't be. That is what is called a farce. <shrug> > > Einstein was a nitwit, a plagiarist, and a liar. There is nothing > > that I can gain from Einstein the nitwit, the plagiarist, and the [quoted text clipped - 3 lines] > recess of the internet that only laughs at you when it isn't ignoring > you. Well, at least I got more stars (one, two, three...) from anyone else. <shrug> > Still that's more attention than you usually get - do your > children or grandchildren ever call you anymore? My children still call me ‘daddy’. <shrug> I have no way to predict what my grand children would call me, but ‘grandpa’ is a likely bet. <shrug> > Oh, so you have *no* emotional investment in Einstein? That is very correct. > Even though you > have spent several years defaming and generally lying your a.s off > about him personally and professionally? What lies? Einstein being a nitwit, a plagiarist, and a liar is no lie. <shrug> > I think people who act like that are called sociopaths. I think people like yourself who denies the truth are called ignorant. <shrug> > The choices here are "sociopath" or "liar". Which are you? Neither. <shrug> > > Well, there is nothing to capitalize on Einstein the nitwit, the > > plagiarist, and the liar. <shrug> > > Other than the attention you get by making the claims. Einstein being a nitwit, a plagiarist, and a liar is the truth when discussing about Einstein. <shrug> > A little ignorance [GR is not based on 'gages'] combined with a whole > lot of arrogance does not an argument make. YOU might not think [quoted text clipped - 5 lines] > Again - who are you to make that call? You are unable to demonstrate > competence in the tools you criticize. This is because I do not see the emperor’s clothes as everyone is peer- pressured into claiming so. <shrug> > > Hey, this is a public newsgroup discussion, is it not? Why are you so > > devastated? You must be taking this very personally. <shrug> > > I'm more devastated that my cheap gungzhao chinese sh.t fireworks > don't work worth a damn. So, you are racist again the Chinese among many other groups. > I'm sure the roll of black cats will make up > the difference though! How is that? > Actually I'm more devastated that my legs are covered in mosquito > bites. It is understandable. At least, your private part did not get chewed up by fleas. Now, that is something for you to avoid sitting on certain grass at all cost. <shrug> > Little f.ckers are out for blood tonight. Try the ancient incent stuff. That seems to work very well whenever I go out backpacking. > > You need to concentrating on getting your degree first before you can > > criticizing others. > > Multitasking, kooby! Multitasking! Yes, we all do in real life. <shrug> > Not just a feature of a modern operating system anymore! That is a bad analogy. All you need is one operating system to run a program. <shrug> > > Yes, GR is based on Riemannian geometry, but it is mis-applied. Let’s > > try this again. The geometry must be invariant. To describe the [quoted text clipped - 4 lines] > you can't even use the terms right despite several years of > corrections? That is because you do not understand the subject. <shrug> > The phrase "the geometry must be invariant" has no > meaning to anyone but yourself and those who have the kooby<-->GR > dictionary. So, the contra argument that you are embracing is that the actual geometry must vary in accordance to each observation. That means you embrace the darkside of art. You must think yourself to be a warlock. <shrug> > Your whining touches on a larger scale of ignorance than you have yet > mentioned. Evaluate the good ol' metric tensor in Euclidean geometry > for Cartesian and then spherical coordinates. What's the difference? > NOTHING. You haven't managed to explain your way past that simple > SIMPLE example since I started bringing it up in when...2006? We have discussed this before. Given an identify metric in 3 dimensional space does not mean space is flat. On the other hand, given a non-diagonal metric does not mean space is curved. You still have to take the choice of coordinate system into account. <shrug> > > If you call the geodesic equations as part of GR, then yes part of GR > > is based on the Lagrangian method. However, since geodesic equations [quoted text clipped - 3 lines] > So you think GR isn't related to Riemannian geometry even though the > Einstein-Hilbert action is proportional to the Ricci scalar? That depends on how you want to draw an umbrella to include GR. <shrug> > Or do you > still reject the Einstein-Hilbert action on some arbitrary and > capricious basis as per usual? The Einstein-Hilbert action is absolutely nonsense. <shrug> > > Your accusation is cheap. <shrug> > > Then prove me wrong. Already done that in these discussions we had. <shrug> > Again - the Euclidean metric in spherical coordinates is ds^2 = dr^2 + > r^2 [d\theta^2 + sin(\theta)^2 d\phi^2]. Prove that the surface area > of a sphere in this specific metric is 4 pi r^2. Its' like 8 lines of > math, why are you afraid of proving me wrong with 8 lines of near- > trivial calculus? I had done that. <shrug> > You are not able to fill in the steps between writing the Euclidean > metric in spherical coordinates and writing "the surface area of a > sphere is 4 pi r^2". You are still barking up the wrong tree. <shrug> > Since you like to harp on me being in school, I'll relay a relevant > example. If you are assigned a problem and you simply write down what > you think the answer is, you will get zero points whether it is right > or not. Your assignment to me of a problem is absolutely ridiculous. <shrug> > > Did I say something wrong? Are you not a multi-year super senior > > without a BA/BS degree still? > > Keep on firing, kooby. I'll discuss my personal life with you when you > stop posting under a pseudonym and join in the discussion under equal > terms. Please keep your personal life or lack of it to yourself. I do not want to know how badly your private part is chewed up by mosquitoes. <shrug> > > Daydreaming about disposing your opponent is sometimes very healthy > > fro your mind especially after your *ss has been kicked so badly by > > your opponent. <shrug> > > You are hallucinating. I blame whatever drugs you are on. Which drug is that? > > Keep guessing. Are you helping Professor Draper to find out which > > university gave me all these degrees? I would very much to be there [quoted text clipped - 7 lines] > display competence in even basic calculus, much less the complicated > subjects you routinely rant about. Keep bitching. <shrug> YKhan wrote on Thu, 03 Jul 2008 12:28:28 -0700: > On Jul 2, 5:25 am, "Juan R." González-Álvarez > <juanREM...@canonicalscience.com> wrote: [quoted text clipped - 7 lines] > useful thing that Strings will have derived. Finally make it something > other than a sci-fi theory. Everything in string theory is largely speculative. But the point was that MOND and relativistic MOND are not just phenomenological approaches, as CDM people often claims. I already cited this preprint in the list of modern references I recommended to Sam http://arxiv.org/abs/hep-th/0703156 I myself am working in a different foundation, that even would give the value for Milgrom's a_0. My goal is to explain why MOND has works as well with a precision unmatched by the best CDM models. This part of my work is still speculative but I applied the new generalized theory to cases where we know for sure that dark matter models do not work and the new theory seems to work fine. >> Personally I would prefer another foundation for MOND, but the idea >> that MOND is just "curve fitting" is another myth promoted by CDM fans. > > MOND and Teves aren't the only theories on the block. John Moffat has > another theory called MOG. I don't know if its derived from MOND, but I > suspect that it predates MOND. http://en.wikipedia.org/wiki/Nonsymmetric_gravitational_theory http://arxiv.org/abs/astro-ph/0608675 Apart from Moffat's one, there are several other theories on literature: PCG, AQUAL... SignatureCenter for CANONICAL |SCIENCE) http://canonicalscience.org > > [...] > [quoted text clipped - 4 lines] > ROFL! Yeah, I'd say they need to think about this some more. I > couldn't have said it better. Its' either that or play "jump to conclusions". > > On the other hand, any article about MOND that tries to evangelize the > > theory and vilify DM that /does not mention/ DM is automagically [quoted text clipped - 7 lines] > there are no galaxies, but it's also *not* in places where there are > galaxies. I thought DM was only supposed to exist in galaxies? I think its' /interesting/, but not especially /disturbing/. Maybe I'm not perturbed as easily as other scientists, or something. I was not aware that DM's existence was chained to anything particular, just that galaxies and DM are usually found together. My personal opinion is that the DM halos formed with the galaxy. However, with the bullet cluster lensing results we can see that the DM is detachable which is no terrible surprise if the assumption that DM is an actual particle of some sort. > That would be my first clue that perhaps the lensing effect is due to > something other than DM and/or gravity in general. Try not to think about Abell 520 in isolation - take the bullet cluster in context. Though listening to ideas that there is some supposed force between DM is a step beyond what I'm willing to assume, I think it should be remembered that we ascribe /very little/ to DM past it being electromagnetically neutral and pressureless. Past that, its' up in the air. > > How exactly is Abell 520 something that conclusively blows dark matter > > out of the water? Lensing observations that directly map mass have > > ruled out MOND, though that hasn't stopped the MOND/TeVeS crew from > > claiming they "can" explain everything. > > There's no proof the lensing effect is due to mass or gravity. No more than time dilation in muon decay is proof of special relativity - it simply confirms the theory and doesn't disprove it. Lensing is still the result of mass in TeVeS, for example. The characterization of what generates the lensing is different, though. It is simply the case that to my knowledge there has never been a confirmed case of lensing that was _not_ due to mass. If there is a even vaguely credible alternate theory, then let's see what it says. > To me, > the lensing effect looks very much like the lensing effect of [quoted text clipped - 4 lines] > could simply be the initial numerical approximations of the deeper > fluidic reality. You cannot view these events in isolation. Why is what we call DM only being seen like this in colliding clusters then? > > As far as using a particular theory to explain individual galactic > > dynamics is concerned, MOND is the clear winner regardless of who is [quoted text clipped - 10 lines] > > Yousuf Khan The fact of life is that complicated things need computers to solve the associated differential equations. Hell - look at the paper regarding MOND in this thread. The only way McGauch was able to obtain the MOND prediction [on top of a particular bitch I have..] was by numerical simulation. > > > Yea, most DM articles aren't going to mention Abell 520 - and why > > > would they? Nothing conclusive can be derived from the cluster, other [quoted text clipped - 4 lines] > > Its' either that or play "jump to conclusions" |
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