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THE OLD RAT SENTENCED TO DEATH:
http://www.prospect-magazine.co.uk/a...ls.php?id=5538 Paul Davies: "Was Einstein wrong? Einstein's famous equation E=mc2 is the only scientific formula known to just about everyone. The "c" here stands for the speed of light. It is one of the most fundamental of the basic constants of physics. Or is it? In recent years a few maverick scientists have claimed that the speed of light might not be constant at all. Shock, horror! Does this mean the next Great Revolution in Science is just around the corner?" http://roychristopher.com/joao-mague...tier-cosmology "Likewise, Joao Magueijo has radical ideas, but his ideas intend to turn that Einsteinian dogma on its head. Magueijo is trying to pick apart one of Einstein's most impenetrable tenets, the constancy of the speed of light. This idea of a constant speed (about 3×106 meters/ second) is familiar to anyone who is remotely acquainted with modern physics. It is known as the universal speed limit. Nothing can, has, or ever will travel faster than light. Magueijo doesn't buy it. His VSL (Varying Speed of Light) presupposes a speed of light that can be energy or time-space dependent. Before you declare that he's out of his mind, understand that this man received his doctorate from Cambridge, has been a faculty member at Princeton and Cambridge, and is currently a professor at Imperial College, London." http://query.nytimes.com/gst/fullpag...pagewanted=all "As propounded by Einstein as an audaciously confident young patent clerk in 1905, relativity declares that the laws of physics, and in particular the speed of light -- 186,000 miles per second -- are the same no matter where you are or how fast you are moving. Generations of students and philosophers have struggled with the paradoxical consequences of Einstein's deceptively simple notion, which underlies all of modern physics and technology, wrestling with clocks that speed up and slow down, yardsticks that contract and expand and bad jokes using the word ''relative.''......''Perhaps relativity is too restrictive for what we need in quantum gravity,'' Dr. Magueijo said. ''We need to drop a postulate, perhaps the constancy of the speed of light.'' http://www.freerepublic.com/focus/f-news/519406/posts "A GROUP of astronomers and cosmologists has warned that the laws thought to govern the universe, including Albert Einstein's theory of relativity, must be rewritten. The group, which includes Professor Stephen Hawking and Sir Martin Rees, the astronomer royal, say such laws may only work for our universe but not in others that are now also thought to exist. "It is becoming increasingly likely that the rules we had thought were fundamental through time and space are actually just bylaws for our bit of it," said Rees, whose new book, Our Cosmic Habitat, is published next month. "Creation is emerging as even stranger than we thought." Among the ideas facing revision is Einstein's belief that the speed of light must always be the same - 186,000 miles a second in a vacuum. There is growing evidence that light moved much faster during the early stages of our universe. Rees, Hawking and others are so concerned at the impact of such ideas that they recently organised a private conference in Cambridge for more than 30 leading cosmologists." http://www.sciscoop.com/2008/10 "Does the apparently constant speed of light change over the vast stretches of the universe? Would our understanding of black holes, ancient supernovae, dark matter, dark energy, the origins of the universe and its ultimate fate be different if the speed of light were not constant?.....Couldn't it be that the supposed vacuum of space is acting as an interstellar medium to lower the speed of light like some cosmic swimming pool? If so, wouldn't a stick plunged into the pool appear bent as the light is refracted and won't that affect all our observations about the universe. I asked theoretical physicist Leonard Susskind, author of The Black Hole War, recently reviewed in Science Books to explain this apparent anomaly....."You are entirely right," he told me, "there are all sorts of effects on the propagation of light that astronomers and astrophysicists must account for. The point of course is that they (not me) do take these effects into account and correct for them." "In a way this work is very heroic but unheralded," adds Susskind, "An immense amount of extremely brilliant analysis has gone into the detailed corrections that are needed to eliminate these 'spurious' effects so that people like me can just say 'light travels with the speed of light.' So, there you have it. My concern about cosmic swimming pools and bent sticks does indeed apply, but physicists have taken the deviations into account so that other physicists, such as Susskind, who once proved Stephen Hawking wrong, can battle their way to a better understanding of the universe." http://www.newscientist.com/article/...erse-tick.html "General relativity knits together space, time and gravity. Confounding all common sense, how time passes in Einstein's universe depends on what you are doing and where you are. Clocks run faster when the pull of gravity is weaker, so if you live up a skyscraper you age ever so slightly faster than you would if you lived on the ground floor, where Earth's gravitational tug is stronger. "General relativity completely changed our understanding of time," says Carlo Rovelli, a theoretical physicist at the University of the Mediterranean in Marseille, France.....It is still not clear who is right, says John Norton, a philosopher based at the University of Pittsburgh, Pennsylvania. Norton is hesitant to express it, but his instinct - and the consensus in physics - seems to be that space and time exist on their own. The trouble with this idea, though, is that it doesn't sit well with relativity, which describes space-time as a malleable fabric whose geometry can be changed by the gravity of stars, planets and matter." http://www.pitt.edu/~jdnorton/Goodie...age/index.html John Norton: "A common belief among philosophers of physics is that the passage of time of ordinary experience is merely an illusion. The idea is seductive since it explains away the awkward fact that our best physical theories of space and time have yet to capture this passage. I urge that we should resist the idea. We know what illusions are like and how to detect them. Passage exhibits no sign of being an illusion....Following from the work of Einstein, Minkowski and many more, physics has given a wonderfully powerful conception of space and time. Relativity theory, in its most perspicacious form, melds space and time together to form a four-dimensional spacetime. The study of motion in space and and all other processes that unfold in them merely reduce to the study of an odd sort of geometry that prevails in spacetime. In many ways, time turns out to be just like space. In this spacetime geometry, there are differences between space and time. But a difference that somehow captures the passage of time is not to be found. There is no passage of time. There are temporal orderings. We can identify earlier and later stages of temporal processes and everything in between. What we cannot find is a passing of those stages that recapitulates the presentation of the successive moments to our consciousness, all centered on the one preferred moment of "now." At first, that seems like an extraordinary lacuna. It is, it would seem, a failure of our best physical theories of time to capture one of time's most important properties. However the longer one works with the physics, the less worrisome it becomes....I was, I confess, a happy and contented believer that passage is an illusion. It did bother me a little that we seemed to have no idea of just how the news of the moments of time gets to be rationed to consciousness in such rigid doses.....Now consider the passage of time. Is there a comparable reason in the known physics of space and time to dismiss it as an illusion? I know of none. The only stimulus is a negative one. We don't find passage in our present theories and we would like to preserve the vanity that our physical theories of time have captured all the important facts of time. So we protect our vanity by the stratagem of dismissing passage as an illusion." ALWAYS REPRIEVING THE OLD RAT: http://www.amazon.com/Petit-Prince-F.../dp/0156013983 "Hem! Hem! dit le roi, je crois bien que sur ma planète il y a quelque part un vieux rat. Je l'entends la nuit. Tu pourras juger ce vieux rat. Tu le condamneras à mort de temps en temps. Ainsi sa vie dépendra de ta justice. Mais tu le gracieras chaque fois pour l'économiser. Il n'y en a qu'un." http://www.amazon.com/Little-Prince-.../dp/0156012197 "Hum! Hum!" said the king. "I have good reason to believe that somewhere on my planet there is an old rat. I hear him at night. You can judge this old rat. From time to time you will condemn him to death. Thus his life will depend on your justice. But you will pardon him on each occasion; for he must be treated thriftily. He is the only one we have." Pentcho Valev |
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"Pentcho Valev" wrote in message
... THE OLD RAT SENTENCED TO DEATH: http://www.pitt.edu/~jdnorton/Goodie...age/index.html John Norton: "A common belief among philosophers of physics is that the passage of time of ordinary experience is merely an illusion. The idea is seductive since it explains away the awkward fact that our best physical theories of space and time have yet to capture this passage. I urge that we should resist the idea. We know what illusions are like and how to detect them. Passage exhibits no sign of being an illusion....Following from the work of Einstein, Minkowski and many more, physics has given a wonderfully powerful conception of space and time. Relativity theory, in its most perspicacious form, melds space and time together to form a four-dimensional spacetime. The study of motion in space and and Stop stop repeating repeatign words words you you ****ing ****ing imbecile imbecile. |
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Einstein comdemning the old rat to death in 1954:
http://www.perimeterinstitute.ca/pdf...09145525ca.pdf Albert Einstein 1954: "I consider it entirely possible that physics cannot be based upon the field concept, that is on continuous structures. Then nothing will remain of my whole castle in the air, including the theory of gravitation, but also nothing of the rest of contemporary physics." The statement "physics cannot be based upon the field concept, that is on continuous structures" is somewhat obscure but here are three clues to Einstein's verdict: http://www.pbs.org/wgbh/nova/einstein/genius/ "Genius Among Geniuses" by Thomas Levenson "And then, in June, Einstein completes special relativity, which adds a twist to the story: Einstein's March paper treated light as particles, but special relativity sees light as a continuous field of waves. Alice's Red Queen can accept many impossible things before breakfast, but it takes a supremely confident mind to do so. Einstein, age 26, sees light as wave and particle, picking the attribute he needs to confront each problem in turn. Now that's tough." http://books.google.com/books?id=JokgnS1JtmMC "Relativity and Its Roots" By Banesh Hoffmann p.92: "Moreover, if light consists of particles, as Einstein had suggested in his paper submitted just thirteen weeks before this one, the second principle seems absurd: A stone thrown from a speeding train can do far more damage than one thrown from a train at rest; the speed of the particle is not independent of the motion of the object emitting it. And if we take light to consist of particles and assume that these particles obey Newton's laws, they will conform to Newtonian relativity and thus automatically account for the null result of the Michelson-Morley experiment without recourse to contracting lengths, local time, or Lorentz transformations. Yet, as we have seen, Einstein resisted the temptation to account for the null result in terms of particles of light and simple, familiar Newtonian ideas, and introduced as his second postulate something that was more or less obvious when thought of in terms of waves in an ether." http://www.ekkehard-friebe.de/wallace.htm Bryan Wallace: "Einstein's special relativity theory with his second postulate that the speed of light in space is constant is the linchpin that holds the whole range of modern physics theories together. Shatter this postulate, and modern physics becomes an elaborate farce! (...) The speed of light is c+v." Yet the old rat survives for a simple reason. Replacing Einstein's 1905 false light postulate with its true antithesis, the equation c'=c +v given by Newton's emission theory of light (v is the relative speed of the emitter and the observer), is tantamount to replacing Einstein's theory with Newton's theory, and this is unbearable for Einsteinians. So they are waiting for the genius who would reject Einstein's 1905 false light postulate without killing the old rat (Einstein's relativity). They simply cannot lose the old rat. There is nothing else on their planet: http://www.amazon.com/Petit-Prince-F.../dp/0156013983 "Hem! Hem! dit le roi, je crois bien que sur ma planète il y a quelque part un vieux rat. Je l'entends la nuit. Tu pourras juger ce vieux rat. Tu le condamneras à mort de temps en temps. Ainsi sa vie dépendra de ta justice. Mais tu le gracieras chaque fois pour l'économiser. Il n'y en a qu'un." http://www.amazon.com/Little-Prince-.../dp/0156012197 "Hum! Hum!" said the king. "I have good reason to believe that somewhere on my planet there is an old rat. I hear him at night. You can judge this old rat. From time to time you will condemn him to death. Thus his life will depend on your justice. But you will pardon him on each occasion; for he must be treated thriftily. He is the only one we have." Pentcho Valev |
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Philosophers of science grant the old rat (Einstein's theory) an
eternal reprieve: W. H. Newton-Smith, The rationality of science, Routledge, London, 1981, p. 78: "There has been no theory, no matter how successful, that has not generated some anomalies from its inception until its demise. The generation of anomalies is not a sufficient condition for rejecting a theory. For a theory with anomalies is better than no theory at all." That is, a theory which predicts that an infinitely long object can be trapped inside an infinitely short container and that an Einsteinian travelling with the rivet sees the bug squashed while the bug sees itself alive and kicking is better than no theory at all (Newton's theory seems to be "no theory at all"): http://math.ucr.edu/home/baez/physic...barn_pole.html "These are the props. You own a barn, 40m long, with automatic doors at either end, that can be opened and closed simultaneously by a switch. You also have a pole, 80m long, which of course won't fit in the barn. Now someone takes the pole and tries to run (at nearly the speed of light) through the barn with the pole horizontal. Special Relativity (SR) says that a moving object is contracted in the direction of motion: this is called the Lorentz Contraction. So, if the pole is set in motion lengthwise, then it will contract in the reference frame of a stationary observer.....So, as the pole passes through the barn, there is an instant when it is completely within the barn. At that instant, you close both doors simultaneously, with your switch. Of course, you open them again pretty quickly, but at least momentarily you had the contracted pole shut up in your barn. The runner emerges from the far door unscathed.....If the doors are kept shut the rod will obviously smash into the barn door at one end. If the door withstands this the leading end of the rod will come to rest in the frame of reference of the stationary observer. There can be no such thing as a rigid rod in relativity so the trailing end will not stop immediately and the rod will be compressed beyond the amount it was Lorentz contracted. If it does not explode under the strain and it is sufficiently elastic it will come to rest and start to spring back to its natural shape but since it is too big for the barn the other end is now going to crash into the back door and the rod will be trapped in a compressed state inside the barn." http://hyperphysics.phy-astr.gsu.edu.../bugrivet.html "The bug-rivet paradox is a variation on the twin paradox and is similar to the pole-barn paradox.....The end of the rivet hits the bottom of the hole before the head of the rivet hits the wall. So it looks like the bug is squashed.....All this is nonsense from the bug's point of view. The rivet head hits the wall when the rivet end is just 0.35 cm down in the hole! The rivet doesn't get close to the bug....The paradox is not resolved." Pentcho Valev |
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![]() Pentcho Valev wrote: Philosophers of science grant the old rat (Einstein's theory) an eternal reprieve: W. H. Newton-Smith, The rationality of science, Routledge, London, 1981, p. 78: "There has been no theory, no matter how successful, that has not generated some anomalies from its inception until its demise. The generation of anomalies is not a sufficient condition for rejecting a theory. For a theory with anomalies is better than no theory at all." That is, a theory which predicts that an infinitely long object can be trapped inside an infinitely short container and that an Einsteinian travelling with the rivet sees the bug squashed while the bug sees itself alive and kicking is better than no theory at all (Newton's theory seems to be "no theory at all"): http://math.ucr.edu/home/baez/physic...barn_pole.html "These are the props. You own a barn, 40m long, with automatic doors at either end, that can be opened and closed simultaneously The doors do not close or open simultaneously in both the frame of reference of the barn and the frame of reference of the pole. by a switch. You also have a pole, 80m long, which of course won't fit in the barn. Now someone takes the pole and tries to run (at nearly the speed of light) through the barn with the pole horizontal. Special Relativity (SR) says that a moving object is contracted in the direction of motion: this is called the Lorentz Contraction. So, if the pole is set in motion lengthwise, then it will contract in the reference frame of a stationary observer.....So, as the pole passes through the barn, there is an instant when it is completely within the barn. At that instant, you close both doors simultaneously, with your switch. Of course, you open them again pretty quickly, but at least momentarily you had the contracted pole shut up in your barn. The runner emerges from the far door unscathed.....If the doors are kept shut the rod will obviously smash into the barn door at one end. If the door withstands this the leading end of the rod will come to rest in the frame of reference of the stationary observer. There can be no such thing as a rigid rod in relativity so the trailing end will not stop immediately and the rod will be compressed beyond the amount it was Lorentz contracted. If it does not explode under the strain and it is sufficiently elastic it will come to rest and start to spring back to its natural shape but since it is too big for the barn the other end is now going to crash into the back door and the rod will be trapped in a compressed state inside the barn." http://hyperphysics.phy-astr.gsu.edu.../bugrivet.html "The bug-rivet paradox is a variation on the twin paradox and is similar to the pole-barn paradox.....The end of the rivet hits the bottom of the hole before the head of the rivet hits the wall. So it looks like the bug is squashed.....All this is nonsense from the bug's point of view. The rivet head hits the wall when the rivet end is just 0.35 cm down in the hole! The rivet doesn't get close to the bug....The paradox is not resolved." http://www.physicsforums.com/archive...p/t-57063.html Have I mentioned recently that you're a moron? -- hz sci.logic |
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The journal NATURE reprieving relativity:
http://www.nature.com/news/2007/0709...070903-20.html Philip Ball, a consultant editor for Natu "Arthur Eddington was innocent! (...) One of the more recent victims of this revised thinking is the 'confirmation' of Einstein's theory of general relativity, offered in 1919 by the British astronomer Arthur Eddington. Eddington reported observing the bending of light during a total eclipse, as predicted by Einstein. But some have claimed that he cooked his books to make sure that Einstein was vindicated over Newton, because Eddington had already decided that this must be so. Now, even physicists who celebrate Einstein's theory commonly charge Eddington with over-interpreting his data. In his Brief History of Time, Stephen Hawking says of the result that: "Their measurement had been sheer luck, or a case of knowing the result they wanted to get." Hawking reports the widespread view that the errors in the data were as big as the effect they were meant to probe. Some go further, saying that Eddington deliberately excluded data that didn't agree with Einstein's prediction. Is that true? According to a study by Daniel Kennefick, a physicist at the University of Arkansas in Fayetteville, Eddington was in fact completely justified in asserting that his measurements matched the prediction of general relativity. Kennefick thinks that anyone now presented with the same data would have to share Eddington's conclusion." Now Philip Ball will have to prove that Eddington was innocent in performing the third classical test of general relativity - when he UNDERESTIMATED THE TRUE SIRIUS B GRAVITATIONAL REDSHIFT BY A FACTOR OF FOUR (see below). The three classical tests of Einstein's general relativity - the 1919 measurement of the deflection of starlight, Mercury's anomalous perihelion advance and Eddington's estimate and Adams' measurement of Sirius B gravitational redshift: http://www.newscientist.com/article/...to-albert.html New Scientist: Ode to Albert "Enter another piece of luck for Einstein. We now know that the light- bending effect was actually too small for Eddington to have discerned at that time. Had Eddington not been so receptive to Einstein's theory, he might not have reached such strong conclusions so soon, and the world would have had to wait for more accurate eclipse measurements to confirm general relativity." http://www.amazon.com/Brief-History-.../dp/0553380168 Stephen Hawking: "Einsteins prediction of light deflection could not be tested immediately in 1915, because the First World War was in progress, and it was not until 1919 that a British expedition, observing an eclipse from West Africa, showed that light was indeed deflected by the sun, just as predicted by the theory. This proof of a German theory by British scientists was hailed as a great act of reconciliation between the two countries after the war. It is ionic, therefore, that later examination of the photographs taken on that expedition showed the errors were as great as the effect they were trying to measure. Their measurement had been sheer luck, or a case of knowing the result they wanted to get, not an uncommon occurrence in science." http://discovermagazine.com/2008/mar...out-relativity "The eclipse experiment finally happened in 1919 (youre looking at it on this very page). Eminent British physicist Arthur Eddington declared general relativity a success, catapulting Einstein into fame and onto coffee mugs. In retrospect, it seems that Eddington fudged the results, throwing out photos that showed the wrong outcome. No wonder nobody noticed: At the time of Einsteins death in 1955, scientists still had almost no evidence of general relativity in action." http://www.cieletespace.fr/evenement...taient-fausses Jean-Marc Bonnet-Bidaud: "L'expédition britannique envoie deux équipes indépendantes sur le trajet de l'éclipse : l'une dirigée par Andrew Crommelin dans la ville de Sobral, dans le nord du Brésil, l'autre conduite par Eddington lui-même sur l'île de Principe, en face de Libreville, au Gabon. Le matériel embarqué est des plus sommaires au regard des moyens actuels : une lunette astronomique de seulement 20 cm de diamètre en chaque lieu, avec un instrument de secours de 10 cm à Sobral. Pour éviter l'emploi d'une monture mécanique trop lourde à transporter, la lumière est dirigée vers les lunettes par de simples miroirs mobiles, ce qui se révélera être une bien mauvaise idée. La stratégie est assez complexe. Il s'agit d'exposer des plaques photographiques durant l'éclipse pour enregistrer la position d'un maximum d'étoiles autour du Soleil, puis de comparer avec des plaques témoins de la même région du ciel obtenues de nuit, quelques mois plus tard. La différence des positions entre les deux séries de plaques, avec et sans le Soleil, serait la preuve de l'effet de la relativité et le résultat est bien sûr connu à l'avance. Problème non négligeable : la différence attendue est minuscule. Au maximum, au bord même du Soleil, l'écart prévu est seulement de un demi dix- millième de degré, soit très précisément 1,75 seconde d'arc (1,75"), correspondant à l'écart entre les deux bords d'une pièce de monnaie observée à 3 km de distance ! Or, quantités d'effets parasites peuvent contaminer les mesures, la qualité de l'émulsion photographique, les variations dans l'atmosphère terrestre, la dilatation des miroirs... Le jour J, l'équipe brésilienne voit le ciel se dégager au dernier moment mais Eddington n'aperçoit l'éclipse qu'à travers les nuages ! Sa quête est très maigre, tout juste deux plaques sur lesquelles on distingue à peine cinq étoiles. Pressé de rentrer en Angleterre, Eddington ne prend même pas la précaution d'attendre les plaques témoins. Les choses vont beaucoup mieux à Sobral : 19 plaques avec plus d'une dizaine d'étoiles et huit plaques prises avec la lunette de secours. L'équipe reste sur place deux mois pour réaliser les fameuses plaques témoins et, le 25 août, tout le monde est en Angleterre. Eddington se lance dans des calculs qu'il est le seul à contrôler, décidant de corriger ses propres mesures avec des plaques obtenues avec un autre instrument, dans une autre région du ciel, autour d'Arcturus. Il conclut finalement à une déviation comprise entre 1,31" et 1,91" : le triomphe d'Einstein est assuré ! Très peu sûr de sa méthode, Eddington attend anxieusement les résultats de l'autre expédition qui arrivent en octobre, comme une douche froide : suivant une méthode d'analyse rigoureuse, l'instrument principal de Sobral a mesuré une déviation de seulement 0,93". La catastrophe est en vue. S'ensuivent de longues tractations entre Eddington et Dyson, directeurs respectifs des observatoires de Cambridge et de Greenwich. On repêche alors les données de la lunette de secours de Sobral, qui a le bon goût de produire comme résultat un confortable 1,98", et le tour de passe-passe est joué. Dans la publication historique de la Royal Society, on lit comme justification une simple note : "Il reste les plaques astrographiques de Sobral qui donnent une déviation de 0,93", discordantes par une quantité au-delà des limites des erreurs accidentelles. Pour les raisons déjà longuement exposées, peu de poids est accordé à cette détermination." Plus loin, apparaît la conclusion catégorique: "Les résultats de Sobral et Principe laissent peu de doute qu'une déviation de la lumière existe au voisinage du Soleil et qu'elle est d'une amplitude exigée par la théorie de la relativité généralisée d'Einstein." Les données gênantes ont donc tout simplement été escamotées." http://alasource.blogs.nouvelobs.com...-deuxieme.html "D'abord il [Einstein] fait une hypothèse fausse (facile à dire aujourd'hui !) dans son équation de départ qui décrit les relations étroites entre géométrie de l'espace et contenu de matière de cet espace. Avec cette hypothèse il tente de calculer l'avance du périhélie de Mercure. Cette petite anomalie (à l'époque) du mouvement de la planète était un mystère. Einstein et Besso aboutissent finalement sur un nombre aberrant et s'aperçoivent qu'en fait le résultat est cent fois trop grand à cause d'une erreur dans la masse du soleil... Mais, même corrigé, le résultat reste loin des observations. Pourtant le physicien ne rejeta pas son idée. "Nous voyons là que si les critères de Popper étaient toujours respectés, la théorie aurait dû être abandonnée", constate, ironique, Etienne Klein. Un coup de main d'un autre ami, Grossmann, sortira Einstein de la difficulté et sa nouvelle équation s'avéra bonne. En quelques jours, il trouve la bonne réponse pour l'avance du périhélie de Mercure..." http://www.cieletespace.fr/evenement...taient-fausses Jean-Marc Bonnet-Bidaud: "L'épilogue du dernier test de la relativité, celui de l'orbite de Mercure, est encore plus passionnant. Ce fut en réalité un test a posteriori de la théorie, puisque la prédiction a fait suite à l'observation et ne l'a pas précédée. L'accord est stupéfiant. Le décalage observé dans la position de Mercure est de 43,11" par siècle, tandis que la prédiction de la relativité est de 42,98" par siècle ! Cette révision de l'horloge cosmique est toujours considérée comme le grand succès d'Einstein, mais elle est encore sous l'épée de Damoclès. En effet, des scientifiques soupçonnent que le Soleil pourrait ne pas être rigoureusement sphérique et un "aplatissement" réel introduirait une correction supplémentaire. La précision actuelle deviendrait alors le talon d'Achille compromettant le bel accord de la théorie." http://www.upd.aas.org/had/meetings/2010Abstracts.html Open Questions Regarding the 1925 Measurement of the Gravitational Redshift of Sirius B Jay B. Holberg Univ. of Arizona. "In January 1924 Arthur Eddington wrote to Walter S. Adams at the Mt. Wilson Observatory suggesting a measurement of the "Einstein shift" in Sirius B and providing an estimate of its magnitude. Adams' 1925 published results agreed remarkably well with Eddington's estimate. Initially this achievement was hailed as the third empirical test of General Relativity (after Mercury's anomalous perihelion advance and the 1919 measurement of the deflection of starlight). IT HAS BEEN KNOWN FOR SOME TIME THAT BOTH EDDINGTON'S ESTIMATE AND ADAMS' MEASUREMENT UNDERESTIMATED THE TRUE SIRIUS B GRAVITATIONAL REDSHIFT BY A FACTOR OF FOUR." http://www.cieletespace.fr/evenement...taient-fausses Jean-Marc Bonnet Bidaud: "Autour de l'étoile brillante Sirius, on découvre une petite étoile, Sirius B, à la fois très chaude et très faiblement lumineuse. Pour expliquer ces deux particularités, il faut supposer que l'étoile est aussi massive que le Soleil et aussi petite qu'une planète comme la Terre. C'est Eddington lui-même qui aboutit à cette conclusion dont il voit vite l'intérêt : avec de telles caractéristiques, ces naines blanches sont extrêmement denses et leur gravité très puissante. Le décalage vers le rouge de la gravitation est donc 100 fois plus élevé que sur le Soleil. Une occasion inespérée pour mesurer enfin quelque chose d'appréciable. Eddington s'adresse aussitôt à Walter Adams, directeur de l'observatoire du mont Wilson, en Californie, afin que le télescope de 2,5 m de diamètre Hooker entreprenne les vérifications. Selon ses estimations, basées sur une température de 8 000 degrés de Sirius B, mesurée par Adams lui-même, le décalage vers le rouge prédit par la relativité, en s'élevant à 20 km/s, devrait être facilement mesurable. Adams mobilise d'urgence le grand télescope et expose 28 plaques photographiques pour réaliser la mesure. Son rapport, publié le 18 mai 1925, est très confus car il mesure des vitesses allant de 2 à 33 km/s. Mais, par le jeu de corrections arbitraires dont personne ne comprendra jamais la logique, le décalage passe finalement à 21 km/s, plus tard corrigé à 19 km/s, et Eddington de conclure : "Les résultats peuvent être considérés comme fournissant une preuve directe de la validité du troisième test de la théorie de la relativité générale." Adams et Eddington se congratulent, ils viennent encore de "prouver" Einstein. Ce résultat, pourtant faux, ne sera pas remis en cause avant 1971. Manque de chance effectivement, la première mesure de température de Sirius B était largement inexacte : au lieu des 8 000 degrés envisagés par Eddington, l'étoile fait en réalité près de 30 000 degrés. Elle est donc beaucoup plus petite, sa gravité est plus intense et le décalage vers le rouge mesurable est de 89 km/s. C'est ce qu'aurait dû trouver Adams sur ses plaques s'il n'avait pas été "influencé" par le calcul erroné d'Eddington. L'écart est tellement flagrant que la suspicion de fraude a bien été envisagée." Pentcho Valev |
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