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PaperCut
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Posts: 1616
Joined: May 14th, 2004, 6:45 pm

Dark Matter Is Crap

March 15th, 2005, 3:38 am

Dark matter - massive yet undetectable, untestable, unproveable. It must exist, because otherwise Newton's equations don't work for really big things (galaxies, et cetera).Is it me? You can't just make up a bunch of untestable crap just to fit the data. This is exactly what they did with the "Ether Wind," more nonsense to try to explain the propagation of light. Now we know better, and the Ether is laughable.Look at it this way: Newton works on ordinary things that we are all familiar with - rockets, baseball trajectories and other macroscopic issues. When you get down to Really Small Things, guess what happens? Newton doesn't work for electrons and their interactions with one another and their nuclei. So? What's the solution? Quantum mechanics - a different set of equations that explains the funny (non-Newtonian) behavior you get. Is there a bridge between these two extremes? Sure. It's called Statistical Mechanics. Fine - all is well.Given that scales of measurement are culpable when it comes to scientific explanations ( or lack thereof), then why do people seem to have a problem believing that we simply need a new set of equations (a Theory) to give explanation to unexpected behavior of Really Big Things?What is more bizarre is that a NYU researcher, Georgi Dvali, has decided that maybe this Dark Matter thing is all wet and his primary tool to suggest an alternative view is - that's right - String Theory. The other Big Fat Untestable Unprovable Bunch of Crap. cf:Crapski.
 
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OMD
Posts: 146
Joined: September 27th, 2004, 1:51 pm

Dark Matter Is Crap

March 15th, 2005, 8:59 am

Come on Papercut!I think it is generally stated very clearly that these are merely theories. One needs to make hypotheses before they prove an assertion. Before a proof is offered, first scientists must think of possible explanations and test things out. I am no astrophysicist, but I am guessing that most experiments and observations have yet to disprove the existence of dark matter/energy, so it will remain a possibility - and that is all - until something significantly more conclusive can be shown - or a better explanation offered that also has no conclusive evidence to give it solid backing. Additionally, while looking for dark matter - and even if it does not exist at all - other things will be discovered that DO have solid scientific backing. Just think of all the relevant mathematics that came from all the people that failed to prove Fermat's last theorem! Something useful will come of these theories one way or another!
 
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DominicConnor
Posts: 11684
Joined: July 14th, 2002, 3:00 am

Dark Matter Is Crap

March 15th, 2005, 9:37 am

You can't just make up a bunch of untestable crap just to fit the data.Interesting philosophical assumptio you make there.We are taught to assume that everything that is "false" about the universe can be proven so by experiment. When we run out of falsehoods, we are left with the truth.There is no a priori reason to believe that we won't at some point bimp into something which does not yield to experimental verification. On a more pedestrian level, there are loads of things about dark matter which admit to testing. It intreacts "weakly" with matter, so this can be tested. I rather suspect that like in so many things what we currently model as a single thing with unified properties is actually several effects who happen to be found together.
 
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OMD
Posts: 146
Joined: September 27th, 2004, 1:51 pm

Dark Matter Is Crap

March 15th, 2005, 9:47 am

QuoteOriginally posted by: DCFCThere is no a priori reason to believe that we won't at some point bump into something which does not yield to experimental verification. I think the inner workings of black holes probably fit into this category. Yahoo! 100 posts - it took only 6 months...though my pace has been much more rapid lately!
Last edited by OMD on March 14th, 2005, 11:00 pm, edited 1 time in total.
 
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farmer
Posts: 13462
Joined: December 16th, 2002, 7:09 am

Dark Matter Is Crap

March 15th, 2005, 10:03 am

QuoteOriginally posted by: DCFCThere is no a priori reason to believe that we won't at some point bimp into something which does not yield to experimental verification.I believe the laws of physics are not fixed, though this property is nearly impossible to observe (whatever subset was held constant enough for whatever creatured God created to do the observing to survive, would then be called "law").
 
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OMD
Posts: 146
Joined: September 27th, 2004, 1:51 pm

Dark Matter Is Crap

March 15th, 2005, 10:06 am

QuoteOriginally posted by: farmerI believe the laws of physics are not fixed, though this property is nearly impossible to observe (whatever subset was held constant enough for whatever creatured God created to do the observing to survive, would then be called "law").I heard an interesting discussion on NPR one time from someone who posed the supposition about what would it mean if the speed of light were not constant throughout the history of time - and the implications it would have on time in and of itself. It was a really long time ago - I wish I could remember all the stuff that was discussed....maybe someone here could recommend some interestingf papers on the subject.
 
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AlanB
Posts: 662
Joined: July 14th, 2002, 3:00 am

Dark Matter Is Crap

March 15th, 2005, 11:44 am

QuoteOriginally posted by: farmerQuoteOriginally posted by: DCFCThere is no a priori reason to believe that we won't at some point bimp into something which does not yield to experimental verification.I believe the laws of physics are not fixed,.....I believe that the laws of physics are fixed - we just don't know all of them to date! I've always had a feeling, deep down, that the constraint that an object can not travel faster than the speed of light is a function of the fact that we haven't observed it and that we simply don't know how to describe the physics. It can't be simply because the mass of the object "blows up" at v=c (again, just a gut feeling).
 
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alexandreC
Posts: 678
Joined: June 9th, 2004, 11:35 pm

Dark Matter Is Crap

March 15th, 2005, 1:26 pm

AlanB, I would suggest you to read about the Michelson-Morley experiment, as well as Einsteins motivations for the two basic principles of special relativity(Relativity principle, which merely states inercial reference frames are all equivelent, and the principle of the volocity of light, read about the gadenkan experiments, of Einstein traveling with a mirror at the speed of liget - when he looks at it, what should he see??!!)These things are actually really easy to read, - and the most complex mathematical concept you should have need is the definition of square root.(of course, things get complicated with the general theory, as the existence of mass changes the topology of space-time, you will need more complex mathematical objects to describe all this, like the metric tensor, Ricci scalars, some way of defining derivatives in these spaces, etc. but the point is; special relativity is prety much straight forward, and its beautiful, so give it a go if you have the time!!)
Last edited by alexandreC on March 14th, 2005, 11:00 pm, edited 1 time in total.
 
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alexandreC
Posts: 678
Joined: June 9th, 2004, 11:35 pm

Dark Matter Is Crap

March 15th, 2005, 1:32 pm

PaperCut, I agree with the others.For example, they were seeing some experiments where the conservation of Energy was not holding true, there was an excess of energy in the end of the experiments. To solve this problem Pauli postulated the existence of the neutrino. Now,as the technology has improved, and other experiments can be made, we know the neutrino indeed exists. (actually, we are now speaking about neutrino oscilations, CP violation, and all that.)so, you will guess that there is an obvious analogy,neutrino-- dark matterenergy conservation -- newtons laws.Obviously, this does not prove the existence of dark matter, but, and accordingly to DCFC's lines,we should not discard the possibility, unless there was clear evindence it does not exist.Alex
Last edited by alexandreC on March 14th, 2005, 11:00 pm, edited 1 time in total.
 
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mikebell
Posts: 1698
Joined: July 1st, 2003, 5:23 am

Dark Matter Is Crap

March 15th, 2005, 1:33 pm

" Astronomers find star-less galaxy" : http://news.bbc.co.uk/1/hi/wales/south_ ... 633.stmAnd someone else explains it this way:QuoteExposing The Myth Of Dark MatterBy David TalbottIn the picture above, something not seen in the inscribed circle has astronomers excited. At an estimated 50 million light-years from Earth, they found a large mass of hydrogen a hundred million times the mass of the Sun-a galaxy of sorts, but containing no stars. Hydrogen gas releases radiation that can be detected at radio wavelengths. Using radio telescopes in England and Puerto Rico, a team of investigators detected the massive cloud in the Virgo Cluster. They named it "VIRGOHI21." The challenge they faced began with the fact that the cloud is rotating way too fast, in apparent defiance of gravity. Without some other force acting on the cloud it should fly apart. The astronomers assumed this force must be gravity. As reported in the BBC story on the discovery, "there must be a stronger gravitational force acting than can be accounted for using visible matter." But this is the same problem posed by galaxies: they rotate too fast for gravity to hold them together. Due to the similarities in rotational dynamics, the investigators of VIRGOHI21 concluded that the remote cloud is a starless "galaxy," held together by the same invisible stuff that they now claim holds all galaxies together -- "dark matter." To give their mathematical models of galaxies integrity, astronomers envision a universe of invisible matter at least five times as voluminous as visible matter. So they've applied the same theories to the hydrogen cloud, except that the proportions of dark matter are much larger. The theorists were not constrained by any consideration other than the calculation of invisible "mass" using their gravitational equations. In this case, however, adding just a little dark matter would not suffice. According to Dr Robert Minchin, of Cardiff University: "From its speed, we realised that VIRGOHI21 was a THOUSAND TIMES more massive than could be accounted for by the observed hydrogen atoms alone." (emphasis ours) One might have thought the investigators would pause in the face of such proportions. To get the results they were looking for, they posited a thousand times more invisible matter than visible matter, with the freedom to place the invisible stuff wherever it is needed for their gravitational equations to work. Is such a leap of faith permissible? The investigators' confidence was undimmed. As reported by Dr Jon Davies, one of the Cardiff team members "The Universe has all sorts of secrets still to reveal to us, but this shows that we are beginning to understand how to look at it in the right way. It's a really exciting discovery." It sounds as if a leap of faith produced an "exciting" scientific breakthrough. But this is the kind of "breakthrough" that causes plasma cosmologists to wonder aloud about the state of science today. They know all too well that it does not take "dark matter" to produce the rapid rotation of a vast hydrogen cloud. Even the weakest electric fields imaginable can routinely achieve such results over vast distances. And since magnetic fields and filamentation -- the most direct pointers to electric currents -- appear everywhere we look in space, the experts on plasma and electricity are growing increasingly impatient with a "science" unwilling to consider the obvious. Dark matter and dark energy field is higly speculative and does require a leap of faith... leap of faith similar to string theory "research".
 
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alexandreC
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Joined: June 9th, 2004, 11:35 pm

Dark Matter Is Crap

March 15th, 2005, 1:36 pm

leap of faith similar to string theory "research". mikebell, what do you mean? "faith", "research"?I call it Research.
Last edited by alexandreC on March 14th, 2005, 11:00 pm, edited 1 time in total.
 
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alexandreC
Posts: 678
Joined: June 9th, 2004, 11:35 pm

Dark Matter Is Crap

March 15th, 2005, 1:50 pm

QuoteOriginally posted by: farmerQuoteOriginally posted by: DCFCThere is no a priori reason to believe that we won't at some point bimp into something which does not yield to experimental verification.I believe the laws of physics are not fixed, though this property is nearly impossible to observe (whatever subset was held constant enough for whatever creatured God created to do the observing to survive, would then be called "law").if the laws of physics are not fixed, then.. they change.if they change there must be a reason for it.Call "Laws of Physics" the reason of the change of your "laws of physics".Also, we identify phenomena in very very far away galaxies, which means that this phenomena has happened hundreds and hundreds of light-years ago.We compare this phenomena with experiments we can preform in the labs, in the present, therefore we can conclude that, in this time scale, there was no change of the laws of physics that describe the experiments under consideration.Alex
Last edited by alexandreC on March 14th, 2005, 11:00 pm, edited 1 time in total.
 
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mikebell
Posts: 1698
Joined: July 1st, 2003, 5:23 am

Dark Matter Is Crap

March 15th, 2005, 2:44 pm

QuoteI call it Research. All right, name one, just one will suffice, experiment which proves or disproves any finding stemming from string theory.
 
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alexandreC
Posts: 678
Joined: June 9th, 2004, 11:35 pm

Dark Matter Is Crap

March 15th, 2005, 4:39 pm

All right, name one, just one will suffice, experiment which proves or disproves any finding stemming from string theory.Name one, any one, experiment that could prove or disprove general relativity,at the time it was being formulated.But still, Einstein was researching, was he not?Like general relativity, you could name plenty of other thories.Some were proven to be wrong, "bien sur", but others survived in time.
Last edited by alexandreC on March 14th, 2005, 11:00 pm, edited 1 time in total.
 
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mdubuque
Posts: 2411
Joined: July 22nd, 2004, 9:04 pm

Dark Matter Is Crap

March 15th, 2005, 5:25 pm

This was an interesting article on superstring theory I thought, with some comparing it to postmodernism....Matthew'Theory of everything' tying researchers up in knots - Keay Davidson, Chronicle Science WriterMonday, March 14, 2005 The most celebrated theory in modern physics faces increasing attacks from skeptics who fear it has lured a generation of researchers down an intellectual dead end. In its original, simplified form, circa the mid-1980s, string theory held that reality consists of infinitesimally small, wiggling objects called strings, which vibrate in ways that yield the different subatomic particles that comprise the cosmos. An analogy is the vibrations on a violin string, which yield different musical notes. Advocates claimed that string theory would smooth out the conflicts between Einsteinian relativity and quantum mechanics. The result, they said, would be a grand unifying "theory of everything," which could explain everything from the nature of matter to the Big Bang to the fate of the cosmos. Over the years, string theory has simultaneously become more frustrating and fabulous. On the one hand, the original theory has become mind-bogglingly complex, one that posits an 11-dimensional universe (far more than the four- dimensional universe of Einstein). The modified theory is so mathematically dense that many Ph.D.-bearing physicists haven't a clue what their string- theorist colleagues are talking about. On the other hand, new versions of the theory suggest our universe is just one of zillions of alternate, invisible -- perhaps even inhabited -- universes where the laws of physics are radically different. String buffs claim this bizarre hypothesis might help to explain various cosmic mysteries. Untestable theory But skeptics suggest it's the latest sign of how string theorists, sometimes called "superstringers," try to colorfully camouflage the theory's flaws, like "a 50-year-old woman wearing way too much lipstick," jokes Robert B. Laughlin, a Nobel Prize-winning physicist at Stanford. "People have been changing string theory in wild ways because it has never worked." Already, the split over string theory has caused tensions at some of the nation's university physics departments. "The physics department at Stanford effectively fissioned over this issue," said Laughlin, now on sabbatical in South Korea. "I think string theory is textbook 'post-modernism' (and) fueled by irresponsible expenditures of money." The dispute could become explosive this year, with the publication of contrarily minded books by two of the best-known and most eloquent scientific popularizers of physics, string theorist Michio Kaku of City University of New York and astrophysicist-particle theorist Lawrence Krauss of Case Western Reserve University in Cleveland. Skeptics have long mocked string theory as untestable, because experimental studies of it would require machines of huge scale, perhaps even as big as the solar system. In his new book "Parallel Worlds" (Doubleday), Kaku disagrees and argues that the first experimental evidence for string theory might begin to emerge within several years from experiments with scientific instruments such as a new particle accelerator, the Large Hadron Collider, which opens for business near Geneva in 2007. Wormhole travel Kaku, whose previous books include the acclaimed "Hyperspace" and equation-packed textbooks on string theory, also suggests that humans might eventually travel to those alternate universes, perhaps via hypothetical portals in space called wormholes. Such claims dismay Krauss, a leading expert on cosmic dark matter and dark energy who is popularly known as author of a best-seller, "The Physics of Star Trek." In his book "Hiding in the Mirror: The Mysterious Allure of Extra Dimensions," to be published by Viking in September, Krauss argues that string theorists have produced no satisfactory explanations for anything. Krauss believes continued research is worthwhile just in case it pans out. But he said that so far, string theorists have promised far more than they have delivered and have fostered the false impression that string theory is the only feasible way to explain cosmic mysteries. Those who dabble in alternate-universe speculations might be just modern versions of "16th century theologians (who) speculated that spirits and angels emerge from the extra-dimensional universe," says Krauss, who is also an outspoken foe of creationist teaching in schools. A great deal is at stake. Over the last two decades, a generation of brilliant young physicists -- the kinds of proto-Einsteins who historically have led intellectual revolution after revolution -- has flocked to string theory because their professors told them that's where the action was. Now many of them are reaching middle age and have gained tenured posts on prestigious campuses. They're also educating a whole new generation of fresh- faced wannabe string theorists who are thrilled by the publicity that string theory attracts, which has included several best-selling books and a special effects-packed TV extravaganza on PBS. The dispute has split partly along subdisciplinary lines, and mirrors a timeless squabble in the philosophy of science: Which is more important for scientific innovation -- theoretical daring or empirical observations and experiments? "Superstringers have now created a culture in physics departments that is openly disdainful of experiments. ... There is an intellectual struggle going on for the very soul of theoretical physics, and for the hearts and minds of young scientists entering our field," says physicist Zlatko Tesanovic of Johns Hopkins University. String theorists and their foes can't even agree on what constitutes success or failure. For example, the most unexpected and counterintuitive discovery of recent science occurred in the 1990s, when astrophysicists at Berkeley and elsewhere realized the universe is expanding faster with time. The apparent reason: a mysterious dark energy pervades space and drives the accelerated expansion. Critics mock superstringers because their so-called theory of everything failed to predict this colossal discovery. String theorists fire back that no one else predicted it, either, and besides, "string theory is the only approach that has the potential for explaining dark energy" based on pure theory, says John Schwarz, a pioneering string theorist at Caltech. That's because string theory is the only existing hypothesis that holds serious promise of merging the two grandest branches of physics -- the theory of gravity, the basis of cosmological theory; and quantum mechanics, the science of the subatomic realm, Schwarz says. Even so, "it's my impression that more and more physicists are starting to join Krauss as 'skeptical agnostics' about string theory," said mathematician Peter Woit of Columbia University, who offers comments on string- theory developments at his blog: www.math.columbia.edu/~woit/blog/. One possible reason for the sea change is that string theory's ambitions have radically changed since the 1980s. Back then, theorists hoped to develop a string theory that would predict the existence of one universe -- ours, of course -- with its given physical forces and constants, such as the known intensity of gravity and the known electrical charge on the electron. In later years, though, string theorists realized their theory predicted innumerable possible universes with widely varying physical forces and constants. As usual, superstringers and their critics viewed this development differently. To critics, like Woit, it is a disaster for string theory because the sheer number of estimated universes -- equal to the number one followed by 500 zeroes -- is unimaginably large. If true, it means that string theory is so flexible that it can be used to predict almost any kind of universe you want, no matter how crazy, and hence it predicts nothing specific enough to be scientifically interesting. "A theory that can't predict anything is not a scientific theory," Woit says. But what if the universe is unimaginably complex and as jammed with diverse universes as the seas are jammed with diverse fish? That's the thesis of Kaku, who compares the history of string research to "wandering around the desert and then stumbling on a tiny pebble. But when we examine it carefully, we find that it's actually the tip of a gigantic pyramid." "But just as we are about to open the door," Kaku says, "some critics say that it's taking too much time, that the writings are too hard to understand, that (it) is draining resources from other projects, that it's getting too much publicity, that the script seems to be mutating as we go from floor to floor, et cetera, et cetera." Opinions on the theory In an informal Chronicle e-mail survey, the world's physicists expressed widely differing, sometimes emotional, opinions on the dispute over string theory: -- "String theory is anything but a futile effort," said an e-mail from David Gross of UC Santa Barbara, who shared the Nobel Prize in physics last year. Among other accomplishments, it has enabled physicists "to understand, finally, many of the mysteries of black holes. ... I am convinced that string theory, as presently understood, is on the right path, but that this path is quite long, and (perhaps many) further breakthroughs are required." -- "I agree entirely with Larry Krauss," says Nobel Prize-winning physicist Philip Anderson of Princeton University. In academia, "we from outside the (string) field are disturbed by our colleagues' insistence that every new semi-adolescent who has done something in string theory is the greatest genius since Einstein and therefore must occupy yet another tenure track. ... Our sciences are becoming increasingly infected with quasi-theology, a tendency which needs to be openly debated." -- "To the considerable extent that string theory has been developed, it has turned out to be a logically consistent quantum theory of gravity," says string theorist Raphael Bousso of Lawrence Berkeley National Laboratory. "This is a very significant achievement utterly unmatched by any other approach to this problem -- and many have been tried over the past several decades." -- "There has been, in recent years, a pernicious, uncritical hype of string theory," says Carlo Rovelli of the Centre de Physique Theorique in Marseille, France. While the theory is worth developing and is a "very interesting attempt to address the fundamental open problems of physics," he says, "so far it is only an attempt, (one) that has delivered less than what was expected some years ago," and "its uncritical promotion is damaging to science." -- Krauss' charge that string theory "has probably been the least successful 'great' idea in physics" in a century is unfair and premature, replies string physicist Brian Greene of Columbia University, author of two acclaimed books on the topic, including "The Elegant Universe." "That's like someone going into Antonio Stradivari's workshop and complaining about the sound produced by one of his as yet unfinished violins." E-mail Keay Davidson at kdavidson@sfchronicle.com. Page A - 6 URL: http://sfgate.com/cgi-bin/article.cgi?f ... BOURE1.DTL
Last edited by mdubuque on March 14th, 2005, 11:00 pm, edited 1 time in total.
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