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REDISCOVERING HUBBLE'S LAW?
http://physicsworld.com/cws/article/news/47392
"The 2011 Nobel Prize for Physics has been awarded to Saul Perlmutter from the Lawrence Berkeley National Laboratory, US, Adam Riess at Johns Hopkins University, in Baltimore, and Brian Schmidt from the Australian National University, Weston Creek, "for the discovery of the accelerating expansion of the universe through observations of distant supernovae". (...) In 1987 physicists at the Lawrence Berkeley National Laboratory and the University of California at Berkeley initiated the Supernova Cosmology Project (SCP) to hunt for certain distant exploding stars, known as Type Ia supernovae. They hoped to use these stars to calculate, among other things, the rate at which the expansion of the universe was slowing down. (...) In 1998, after years of observations, two rival groups of supernova hunters - the High-Z Supernovae Search Team led by Schmidt and Riess and the SCP led by Perlmutter - came to the conclusion that the cosmic expansion is actually accelerating and not slowing under the influence of gravity as might be expected." Why did they expect the expansion of the universe to slow down? If there is expansion (I think there isn't), Hubble's redshift should have made them expect it to accelerate: http://en.wikipedia.org/wiki/Acceler..._of_the_cosmos "In 1929, American astronomer Edwin Hubble studied the relative velocities of a number of comparatively far-away galaxies and compared the information obtained from this, with estimates of the galaxies' distance from Earth. He found that more distant galaxies appeared to be moving away from the Earth at a faster rate than closer galaxies. This fact became known as Hubble's Law." Pentcho Valev |
#2
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REDISCOVERING HUBBLE'S LAW?
Hubble's Law: V = HD
where V is the velocity of the galaxy, D is the distance to it and H is the Hubble constant. H may vary slightly but as long as it remains positive (H0), the expansion is ACCELERATING. An expansion that IS SLOWING DOWN will obey the equation: dV/dD = -H H is positive again and may vary slightly but the minus sign guarantees the deceleration. Now in two cases a contribution deserves the Nobel prize: 1. The world believes V=HD is true but you prove dV/dD=-H is true. 2. The world believes dV/dD=-H is true but you prove V=HD is true. In any other case the contribution deserves, at best, to be published in a prestigious journal. Pentcho Valev wrote: http://physicsworld.com/cws/article/news/47392 "The 2011 Nobel Prize for Physics has been awarded to Saul Perlmutter from the Lawrence Berkeley National Laboratory, US, Adam Riess at Johns Hopkins University, in Baltimore, and Brian Schmidt from the Australian National University, Weston Creek, "for the discovery of the accelerating expansion of the universe through observations of distant supernovae". (...) In 1987 physicists at the Lawrence Berkeley National Laboratory and the University of California at Berkeley initiated the Supernova Cosmology Project (SCP) to hunt for certain distant exploding stars, known as Type Ia supernovae. They hoped to use these stars to calculate, among other things, the rate at which the expansion of the universe was slowing down. (...) In 1998, after years of observations, two rival groups of supernova hunters - the High-Z Supernovae Search Team led by Schmidt and Riess and the SCP led by Perlmutter - came to the conclusion that the cosmic expansion is actually accelerating and not slowing under the influence of gravity as might be expected." Why did they expect the expansion of the universe to slow down? If there is expansion (I think there isn't), Hubble's redshift should have made them expect it to accelerate: http://en.wikipedia.org/wiki/Acceler..._of_the_cosmos "In 1929, American astronomer Edwin Hubble studied the relative velocities of a number of comparatively far-away galaxies and compared the information obtained from this, with estimates of the galaxies' distance from Earth. He found that more distant galaxies appeared to be moving away from the Earth at a faster rate than closer galaxies. This fact became known as Hubble's Law." Pentcho Valev |
#3
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REDISCOVERING HUBBLE'S LAW?
If distant supernovae are farther away than one would expect based on
the LINEAR increase of red shift with distance, this can be explained on the assumption that, as the photon travels through "empty" space (in a STATIC universe), it loses speed in much the same way that a golf ball loses speed due to the resistance of the air: http://www.citebase.org/fulltext?for...rg%3A0706.2885 An Alternative Explanation for Cosmological Redshift David Schuster Department of Physics and Astronomy, University of Denver "Current models of the intergalactic medium contend that it has mass density on the order of 10^(-27) kg/m^3. While it is true that this equates to approximately one atom of neutral Hydrogen per cubic meter, averaging over cosmological distances, it is reasonable to consider the IGM a super-low density fluid. (...) Obviously, as the density of the intervening medium increases, so does the number of interactions and, consequently, so does the travel time of the light. This is the effect seen in a dense material like calcite where there are so many interactions that THE LIGHT SLOWS DOWN appreciably in a short distance. (...) Assuming the interaction cross-section to correspond to the Bohr radius. This means that a photon will, on average, have an interaction and, accordingly, a characteristic delay every 37600 light years. This is using the minimum particle density in intergalactic space, which can vary widely up to approximately 1000 particles/m^3 in areas of particularly high density." On this analogy the resistive force (Fr) is proportional to the the velocity of the photon (V): Fr = - KV That is, the speed of light decreases in accordance with the equation: dV/dt = - K'V Clearly, at the end of a very long journey of photons (coming from a very distant object), the contribution to the redshift is much smaller than the contribution at the beginning of the journey. Light coming from nearer objects is less subject to this difference, that is, the increase of the redshift with distance is closer to LINEAR. Pentcho Valev |
#4
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REDISCOVERING HUBBLE'S LAW?
The most reasonable question in cosmology:
http://www.sciscoop.com/2008-10-30-41323-484.html "Shine a light through a piece of glass, a swimming pool or any other medium and it slows down ever so slightly, it's why a plunged part way into the surface of a pool appears to be bent. So, what about the space in between those distant astronomical objects and our earthly telescopes? 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?" So far phrases like "TO LOWER THE SPEED OF LIGHT" have been actuating absolute crimestop: http://www.liferesearchuniversal.com/1984-17 George Orwell: "Crimestop means the faculty of stopping short, as though by instinct, at the threshold of any dangerous thought. It includes the power of not grasping analogies, of failing to perceive logical errors, of misunderstanding the simplest arguments if they are inimical to Ingsoc, and of being bored or repelled by any train of thought which is capable of leading in a heretical direction. Crimestop, in short, means protective stupidity." Pentcho Valev |
#5
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REDISCOVERING HUBBLE'S LAW?
How can an intelligent person put up with the idiotic transition from
the original "Doppler" interpretation of the Hubble redshift to the modern universe-expansion-stretches-the-wavelength interpretation? Cosmologists, do all of you teach the following wisdom: http://curious.astro.cornell.edu/que...php?number=278 "In both cases, the light emitted by one body and received by the other will be "redshifted" - i.e. its wavelength will be stretched, so the color of the light is more towards the red end of the spectrum. But there's a subtle difference, which you sort of allude to. In fact, only in the first case (a nearby body moving away from the earth) is the redshift caused by the Doppler effect. You've experienced the Doppler effect if you've ever had a train go past you and heard the whistle go to a lower pitch (corresponding to a longer wavelength for the sound wave) as the train moves away. The Doppler effect can happen for light waves too (though it can't be properly understood without knowing special relativity). It turns out that just like for sound waves, the wavelength of light emitted by an object that is moving away from you is longer when you measure it than it is when measured in the rest frame of the emitting object. In the case of distant objects where the expansion of the universe becomes an important factor, the redshift is referred to as the "cosmological redshift" and it is due to an entirely different effect. According to general relativity, the expansion of the universe does not consist of objects actually moving away from each other - rather, the space between these objects stretches. Any light moving through that space will also be stretched, and its wavelength will increase - i.e. be redshifted. (This is a special case of a more general phenomenon known as the "gravitational redshift" which describes how gravity's effect on spacetime changes the wavelength of light moving through that spacetime. The classic example of the gravitational redshift has been observed on the earth; if you shine a light up to a tower and measure its wavelength when it is received as compared to its wavelength when emitted, you find that the wavelength has increased, and this is due to the fact that the gravitational field of the earth is stronger the closer you get to its surface, causing time to pass slower - or, if you like, to be "stretched" - near the surface and thereby affecting the frequency and hence the wavelength of the light.) Practically speaking, the difference between the two (Doppler redshift and cosmological redshift) is this: in the case of a Doppler shift, the only thing that matters is the relative velocity of the emitting object when the light is emitted compared to that of the receiving object when the light is received. After the light is emitted, it doesn't matter what happens to the emitting object - it won't affect the wavelength of the light that is received. In the case of the cosmological redshift, however, the emitting object is expanding along with the rest of the universe, and if the rate of expansion changes between the time the light is emitted and the time it is received, that will affect the received wavelength. Basically, the cosmological redshift is a measure of the total "stretching" that the universe has undergone between the time the light was emitted and the time it was received." Pentcho Valev |
#6
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REDISCOVERING HUBBLE'S LAW?
Incommensurable texts (that is, texts that would never be juxtaposed)
in Einsteiniana's schizophrenic world: http://ldolphin.org/recentlight.html "However, since a major paper by Andreas Albrecht and Jao Magueijo in 1999, and another one by John Barrow in the same issue of Physical Review D, the speed of light has come under increasing scrutiny as a physical quantity that may be varying. These scientists are saying that if lightspeed was significantly higher at the inception of the cosmos (about 10^60 higher) then a number of astronomical problems can be readily resolved. Paul Davies statements echo that and he, like Barrow, considers that lightspeed has declined over the history of the universe. By contrast, Albrecht and Magueijo contained the lightspeed change to the earliest moments of the Big Bang and had it drop to its present value immediately afterwards. In that sense, this recent work is consolidating the belief that the drop in lightspeed has extended over the whole history of the universe. This is the position that the cDK research has advocated since the early 1980's. The cause of the change in the speed of light has still to be determined, but according to Lineweaver, one of the prime suspects is that the structure of the vacuum has been changing uniformly across the cosmos. This is also the position that the cDK research has advocated since the early to mid 1990's and was formalised a technical paper which has so far been submitted for publication to two physics journals, one astronomy journal and one general science journal and none have been willing to publish it. It is also the key subject of another paper also under review, entitled "Exploring the Vacuum." Because there is an intrinsic energy in every cubic centimetre of the vacuum, this energy may manifest as virtual particle pairs like electron/positron pairs that flit in and out of existence. As a photon of light travels through the vacuum, it hits a virtual particle, is absorbed, and then shortly after is re-emitted. This process, while fast, still takes a finite time to occur. Thus, a photon of light is like a runner going over hurdles. The more hurdles over a set distance on the track the longer it takes for runners to reach their destination. Thus, if the energy content of space increased with time, more virtual particles would manifest per unit distance, and so the longer light would take to reach its destination." http://www.npr.org/2011/10/07/141156...ating-universe Nobelist Adam Riess: "Yes, well, you know, I think the best candidate remains our understanding the vacuum in a sort of quantum mechanical sense, that there is what we call a zero-point energy to the vacuum, that is the energy - the vacuum is a much livelier and more interesting place than we learned about in high school chemistry - there are particles flitting in and out of existence - and that the sum energy associated with all those gives rise to, on a macroscopic scale, this thing we call dark energy." Pentcho Valev |
#7
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REDISCOVERING HUBBLE'S LAW?
Intrinsic redshift:
http://arstechnica.com/science/news/...dshif-test.ars "Light emitted by distant objects rarely makes it to Earth at the same wavelength that it started out at. The fabric of the Universe is expanding, which causes a redshift. Most objects are also moving relative to the Earth, which adds a Doppler shift to the light. Finally, light that has to climb out of a large gravity well on its way to Earth also gets red-shifted." How can Einsteinians claim that "light that has to climb out of a large gravity well on its way to Earth also gets red-shifted" and reject Halton Arp's intrinsic redshift at the same time? In Einsteiniana's schizophrenic world texts referring to the gravitational redshift are incommensurable (never appear together) with texts referring to the fact that, according to Einstein's general relativity, the speed of light varies with the gravitational potential. That is, according to general relativity, "light that has to climb out of a large gravity well on its way to Earth", on its arrival, has a speed lower than c: http://www.speed-light.info/speed_of_light_variable.htm "Einstein wrote this paper in 1911 in German. It predated the full formal development of general relativity by about four years. You can find an English translation of this paper in the Dover book 'The Principle of Relativity' beginning on page 99; you will find in section 3 of that paper Einstein's derivation of the variable speed of light in a gravitational potential, eqn (3). The result is: c'=c0(1+phi/c^2) where phi is the gravitational potential relative to the point where the speed of light co is measured......You can find a more sophisticated derivation later by Einstein (1955) from the full theory of general relativity in the weak field approximation....For the 1955 results but not in coordinates see page 93, eqn (6.28): c(r)=[1+2phi(r)/c^2]c. Namely the 1955 approximation shows a variation in km/sec twice as much as first predicted in 1911." http://www.mathpages.com/rr/s6-01/6-01.htm "Around 1911 Einstein proposed to incorporate gravitation into a modified version of special relativity by allowing the speed of light to vary as a scalar from place to place in Euclidean space as a function of the gravitational potential. This "scalar c field" is remarkably similar to a simple refractive medium, in which the speed of light varies as a function of the density. Fermat's principle of least time can then be applied to define the paths of light rays as geodesics in the spacetime manifold (as discussed in Section 8.4). Specifically, Einstein wrote in 1911 that the speed of light at a place with the gravitational potential phi would be c(1+phi/c^2), where c is the nominal speed of light in the absence of gravity. In geometrical units we define c=1, so Einstein's 1911 formula can be written simply as c'=1+phi. However, this formula for the speed of light (not to mention this whole approach to gravity) turned out to be incorrect, as Einstein realized during the years leading up to 1915 and the completion of the general theory. (...) ...we have c_r =1+2phi, which corresponds to Einstein's 1911 equation, except that we have a factor of 2 instead of 1 on the potential term." Pentcho Valev |
#8
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REDISCOVERING HUBBLE'S LAW?
The only reason behind Dark Energy:
http://www.physorg.com/news179508040.html "More than a dozen ground-based Dark Energy projects are proposed or under way, and at least four space-based missions, each of the order of a billion dollars, are at the design concept stage." http://www.laprovence.com/article/a-...du-cote-obscur "Dark Vador peut aller se rhabiller. Les Marseillais sont du côté obscur et pour une fois, personne ne leur en fera le reproche. C'est même une fierté au Laboratoire d'astrophysique de Marseille (LAM) qui vient d'être choisi pour participer à l'une des deux missions phares de l'Agence spatiale européenne pour les dix ans à venir sur l'énergie et la matière noires. Celle qui constitue l'essentiel de notre univers et qui serait à l'origine de l'expansion de l'accélération de l'univers. 800 millions d'euros. Cette mission, baptisée Euclid, du nom du mathématicien fondateur de la géométrie qui porte son nom, va être dotée d'un budget de quelque 800 millions d'euros et mobiliser 700 personnes en Europe et donc une cinquantaine dans la région provençale." So even if dark energy were 10 times sillier, scientists will continue to worship it, Nobel prizes will go in that direction etc. Billions are billions! http://io9.com/5607692/are-physicist...up-dark-energy Dave Goldberg, Associate Professor of Physics at Drexel University: "The idea of dark energy is so ridiculous that almost every question is based on trying to make it go away. And believe me, I share your concerns. I don't want to believe in dark energy, but I have no choice. (...) Basically, if you want to get rid of dark energy, you have to get rid of relativity." http://www.smithsonianmag.com/scienc.../87150187.html "Dark Energy: The Biggest Mystery in the Universe (...) "We have a complete inventory of the universe," Sean Carroll, a California Institute of Technology cosmologist, has said, "and it makes no sense." http://www.nytimes.com/2010/01/26/science/26essay.html "The worrying continued. Lawrence Krauss, a cosmologist from Arizona State, said that most theories were wrong. "We get the notions they are right because we keep talking about them," he said. Not only are most theories wrong, he said, but most data are also wrong..." http://io9.com/5528758/ask-a-physici...in-dark-matter Dave Goldberg, Associate Professor of Physics at Drexel University: "And don't even get me started about Dark Energy. It's the stuff that accelerates the universe, and if you think you've got a problem with Dark Matter, wait'll you see Dark Energy. It's no so much that we don't understand where Dark Energy could come from; it's just that the "natural" value (the one that comes out of reasonable assumptions based on vacuum energy) is about 10^100 times the density that we actually observe. For my money, this is the absolute biggest problem in physics." Pentcho Valev |
#9
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REDISCOVERING HUBBLE'S LAW?
Dark energy and Nobel prize:
http://www.latimes.com/news/opinion/...,5744065.story "The other question: What is this antigravity force, anyway? Theoretical physicists call it dark energy, but do they have ideas about what it actually is, how it works? Plenty, but are they convincing? "Well, no," Riess said in a telephone interview last week. "They really aren't." Another Nobel awaits whoever figures that one out." Note that no Nobel awaits those who, appalled at the dark idiocy, choose the reasonable explanation Hubble himself had chosen: http://www.springerlink.com/content/...0/fulltext.pdf Misconceptions about the Hubble recession law Wilfred H. Sorrell, Astrophys Space Sci "Reber (1982) pointed out that Hubble himself was never an advocate for the expanding universe idea. Indeed, it was Hubble who personally thought that a model universe based on the tired-light hypothesis is more simple and less irrational than a model universe based on an expanding spacetime geometry (...) ...any photon gradually loses its energy while traveling over a large distance in the vast space of the universe." http://www.time.com/time/magazine/ar...757145,00.html Monday, Dec. 14, 1936: "Other causes for the redshift were suggested, such as cosmic dust or a change in the nature of light over great stretches of space. Two years ago Dr. Hubble admitted that the expanding universe might be an illusion, but implied that this was a cautious and colorless view. Last week it was apparent that he had shifted his position even further away from a literal interpretation of the redshift, that he now regards the expanding universe as more improbable than a non-expanding one." Pentcho Valev |
#10
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REDISCOVERING HUBBLE'S LAW?
Sane voices in Einsteiniana's schizophrenic world:
http://www.scientificamerican.com/po...ysics-11-10-04 Frank Atkinson (comment 6): "I warmly applaud the accurate observatonal work of the prize winners - on supernovae. However, the Prize was awarded on the grounds of the work showing that the Universe is expanding at an accelerating rate but this is merely conjectue based on the prior guess that the Universe is actually expanding. It seems reasonable to expect the elimination of prior guesswork before handing out prestigious Prizes. All the facts relied on for an expanding Universe have alternatie explanations. For example we know the redshift is not due to the Doppler effect. or we would have to be at the centre of the Universe. Problematically, the Doppler effect is the only proved redshift effect caused by motion, others are guesswork. However, a model called the cosmological redshift, has been fabricated, to make the redshift be a measure of a notional expansion. This relies on the expansion being produced by space itself stretching and pushing galaxies apart. The redshift is then said to be caused by the expanding space, stretching the wavelength of light as it passes through it. There is no known method for either space to stretch and expand or for it to stretch light as it passes through it. This model is pure metaphysical speculation." Pentcho Valev wrote: How can an intelligent person put up with the idiotic transition from the original "Doppler" interpretation of the Hubble redshift to the modern universe-expansion-stretches-the-wavelength interpretation? Cosmologists, do all of you teach the following wisdom: http://curious.astro.cornell.edu/que...php?number=278 "In both cases, the light emitted by one body and received by the other will be "redshifted" - i.e. its wavelength will be stretched, so the color of the light is more towards the red end of the spectrum. But there's a subtle difference, which you sort of allude to. In fact, only in the first case (a nearby body moving away from the earth) is the redshift caused by the Doppler effect. You've experienced the Doppler effect if you've ever had a train go past you and heard the whistle go to a lower pitch (corresponding to a longer wavelength for the sound wave) as the train moves away. The Doppler effect can happen for light waves too (though it can't be properly understood without knowing special relativity). It turns out that just like for sound waves, the wavelength of light emitted by an object that is moving away from you is longer when you measure it than it is when measured in the rest frame of the emitting object. In the case of distant objects where the expansion of the universe becomes an important factor, the redshift is referred to as the "cosmological redshift" and it is due to an entirely different effect. According to general relativity, the expansion of the universe does not consist of objects actually moving away from each other - rather, the space between these objects stretches. Any light moving through that space will also be stretched, and its wavelength will increase - i.e. be redshifted. (This is a special case of a more general phenomenon known as the "gravitational redshift" which describes how gravity's effect on spacetime changes the wavelength of light moving through that spacetime. The classic example of the gravitational redshift has been observed on the earth; if you shine a light up to a tower and measure its wavelength when it is received as compared to its wavelength when emitted, you find that the wavelength has increased, and this is due to the fact that the gravitational field of the earth is stronger the closer you get to its surface, causing time to pass slower - or, if you like, to be "stretched" - near the surface and thereby affecting the frequency and hence the wavelength of the light.) Practically speaking, the difference between the two (Doppler redshift and cosmological redshift) is this: in the case of a Doppler shift, the only thing that matters is the relative velocity of the emitting object when the light is emitted compared to that of the receiving object when the light is received. After the light is emitted, it doesn't matter what happens to the emitting object - it won't affect the wavelength of the light that is received. In the case of the cosmological redshift, however, the emitting object is expanding along with the rest of the universe, and if the rate of expansion changes between the time the light is emitted and the time it is received, that will affect the received wavelength. Basically, the cosmological redshift is a measure of the total "stretching" that the universe has undergone between the time the light was emitted and the time it was received." Pentcho Valev |
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