Gravitation is not geometrical
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From: "Juan R." González-Álvarez on 29 Nov 2008 11:58 Sam Wormley wrote on Sat, 29 Nov 2008 14:48:32 +0000: > Juan R. González-Álvarez wrote: >> Albertito wrote on Fri, 28 Nov 2008 11:33:19 -0800: >> >>> On Nov 28, 7:26 pm, "Juan R." González-Álvarez >>> <juanREM...(a)canonicalscience.com> wrote: >>>> Albertito wrote on Fri, 28 Nov 2008 11:20:41 -0800: >>>> >>>>> On Nov 28, 7:08 pm, "Juan R." González-Álvarez >>>>> <juanREM...(a)canonicalscience.com> wrote: >>>>>> Albertito wrote on Fri, 28 Nov 2008 11:03:38 -0800: (snip more >>>>>> misunderstanding) >>>>>> --http://www.canonicalscience.org/ >>>>> what misunderstanding? >>>> *Plural* >>>> >>>> --http://www.canonicalscience.org/ >>> what misunderstandings? >> >> 1) For example, gravitional waves are prediction of relativity. >> >> 2) Since, gravitational waves will never be observed, its >> non-observation never will contradict relativity! >> >> >> >> > Black hoes are predicted by GTR... Have we ever seen black holes? No! > But we see their paw prints! We measure their properties. > > > "A binary pulsar found in 1974 by the American physicists Russell > Hulse and Joseph Taylor of Princeton University, a discovery for > which they shared the 1993 Nobel prize in physics. It consists of a > pulsar (a neutron star) with a pulsation period of 59 milliseconds > (equal to 17 pulses per second) and a companion that move around each > other in an elongated orbit (period 7.75 hours, periastron 1.1 Rsun, > apastron 4.8 Rsun). > > "Although the nature of the companion is not known for certain, it is > thought to have the same mass as the pulsar (1.4 Msun) and so is > probably also a neutron star. The orbit is gradually shrinking, by > about 3.1 mm per orbit, because of gravitational waves as predicted > by the general theory of relativity. > > "This will cause the two stars to merge – about 300 million years > from now. The extreme density and small orbital radius of this system > results in a huge orbital precession of 4.2° per year, exactly in > agreement with the value predicted by the general theory of > relativity. Indeed, PSR 1913+16 has proved to be a rich > testing-ground for gravitational theories. > > "One interesting aspect is that the period of the orbit is gradually > shortening as the pulsars spiral towards each other. This implies a > loss of energy, similar to that of an artificial satellite as its > orbit gradually decays due to atmospheric drag; the rate at which the > decay is happening is consistent with the radiation of energy via > gravitational waves, again as predicted by Einstein's theory". Relax -- http://www.canonicalscience.org/
From: "Juan R." González-Álvarez on 29 Nov 2008 12:01 Sam Wormley wrote on Sat, 29 Nov 2008 14:52:52 +0000: > As I said, you misunderstand the significance of Russell Hulse and > Joseph Taylor's work with PSR 1913+16. Both received a Nobel for discovering of the famous binary pulsar, just that. 1) Gravitational waves have been never detected. Everything about pulsar is about indirect tests. 2) Last high precision observations reveals that binary pulsar is better described by non-geometrical theory of gravity which gives the same prediction than GR more a 1% excess cannot be explained using GR. -- http://www.canonicalscience.org/
From: "Juan R." González-Álvarez on 29 Nov 2008 13:19 Sam Wormley wrote on Sat, 29 Nov 2008 17:56:24 +0000: >> Relax >> >> > I was all along. Relax more :-) -- http://www.canonicalscience.org/
From: "Juan R." González-Álvarez on 29 Nov 2008 13:27 eric gisse wrote on Sat, 29 Nov 2008 08:29:18 -0900: > On Sat, 29 Nov 2008 18:01:33 +0100 (CET), "Juan R." González-Álvarez > <juanREMOVE(a)canonicalscience.com> wrote: > >>Sam Wormley wrote on Sat, 29 Nov 2008 14:52:52 +0000: >> >>> As I said, you misunderstand the significance of Russell Hulse and >>> Joseph Taylor's work with PSR 1913+16. >> >>Both received a Nobel for discovering of the famous binary pulsar, just >>that. > > No, they recieved the Nobel for discovering that the pulsar's components > were decaying exactly in accordance with general relativity's prediction > of gravitational radiation. Crackpot, why do you insist on trying to find a mistake in my posts? Do you feel some need to be permanently ridiculed in public? :-) From the Nobel commite: (\blockquote The Royal Swedish Academy of Sciences has decided to award the Nobel Prize Physics for 1993 jointly to Russell A. Hulse and Joseph H. Taylor, Jr, both of Princeton University, New Jersey, USA *FOR* the discovery of a new type of pulsar, a discovery that has opened up new possibilities for the study of gravitation ) >>1) Gravitational waves have been never detected. Everything about >> pulsar is about indirect tests. >> >>2) Last high precision observations reveals that binary pulsar is >> better >> described by non-geometrical theory of gravity which gives the same >> prediction than GR more a 1% excess cannot be explained using GR. > > Let's see the literature reference. Why would waste time with a crackpot liar as you? :-) -- http://www.canonicalscience.org/
From: "Juan R." González-Álvarez on 29 Nov 2008 13:47
Sam Wormley wrote on Sat, 29 Nov 2008 18:39:30 +0000: > Juan R. González-Álvarez wrote: > > >> From the Nobel commite: >> >> (\blockquote >> The Royal Swedish Academy of Sciences has decided to award the Nobel >> Prize Physics for 1993 jointly to Russell A. Hulse and Joseph H. >> Taylor, Jr, both of Princeton University, New Jersey, USA *FOR* the >> discovery of a new type of pulsar, a discovery that has opened up new >> possibilities for the study of gravitation > > Ref: > http://nobelprize.org/nobel_prizes/physics/laureates/1993/press.html > > The press release continues: > > > The significance of the discovery of the binary pulsar > > The discovery of the first binary pulsar is primarily of great > significance for astrophysics and gravitational physics. Gravity is the > oldest known natural force, the one we are most aware of in daily life. > At the same time it is in one sense the force that is hardest to study > since it is so much weaker than the other three natural forces: the > electromagnetic force and the strong and the weak nuclear forces. The > development of technology and science since the second World War with > rockets, satellites, space voyages, radioastronomy, radar technology and > the precise measurement of time using atomic clocks has led to a > renaissance of the study of this earliest-known natural force. The > discovery of the binary pulsar represents an important milestone in this > historical development. > > Relativity theory and gravitational physics > > According to Albert Einstein's general theory of relativity, gravity is > caused by changes in the geometry of space and time: space-time curves > near masses. Einstein presented his theory in 1915 and became a world > celebrity when in 1919 the English astrophysicist Arthur Eddington > announced that one of the predictions of the theory, the deflection of > starlight passing near the surface of the sun - "the light is drawn > towards the sun" - had been verified during solar eclipse expeditions. > This deflection of light. together with a small general-relativity > contribution to the perihelion motion of Mercury (a slow rotation of > Mercury's elliptical orbit round the sun), was for several decades the > only, partly rather uncertain, support for Einstein's theory. > > For a long time the theory of relativity was considered aesthetically > very beautiful and satisfying, probably correct, but of little practical > significance to physics except in applications in cosmology, the study > of the origin, development and structure of the universe. > > Attitudes to the general theory of relativity changed, however, during > the 1960s when both experimental and theoretical developments made > gravitational physics a topical part of physics. New opportunities for > precise experiments, based on satellite and radar technology, opened up. > In particular, the research of the Americans R. Dicke and I. Shapiro > contributed to this. Dicke performed precision experiments in which the > sun's gravitational field on the earth was used for verifying what is > termed the equivalence principle, the identity between gravitational and > inertial mass - one of the basic principles of the general theory of > relativity (and also of several alternative gravitation theories). > Important contributions were also Shapiro's theoretical prediction and > experimental verification, using radar echoes from Mercury, of a new > consequence of the general theory of relativity - a time-delay effect > for electromagnetic signals passing through gravitational fields. > > All these experiments, however, were confined to our solar system with > its very weak gravitational fields and consequently small deviations, > hard,to measure, from the Newtonian theory of gravity. Hence it was > possible to test the general theory of relativity and other theories > only in the first post-Newtonian approximation. > > The discovery of the binary pulsar > > Hulse's and Taylor's discovery in 1974 of the first binary pulsar, > called PSR 1913 + 16 (PSR stands for pulsar, and 1913 + 16 specifies the > pulsar's position in the sky) thus brought about a revolution in the > field. We have here two very small astronomical bodies, each with a > radius of some ten kilometres but with a mass comparable with that of > the sun, and at a short distance from each other, only several times the > moon's distance from the earth. Here the deviations from Newton's > gravitational physics are large. As an example may be mentioned that the > periastron shift, the rotation of the elliptical orbit that the pulsar > (according to Kepler's first law from the beginning of the 17th century) > follows in this system, is 4 degrees per year. The corresponding > relativistic shift for the most favourable example in our solar system, > the above-mentioned perihelion motion of Mercury, is 43 seconds of arc > per century (this is less than a tenth of the very much larger > contributions to the perihelion motion caused by perturbations from > other planets, chiefly Venus and Jupiter). The difference in size > between the shifts is partly due to the orbital speed in the binary > pulsar, which is almost five times greater than Mercury's, and partly > due to the pulsar performing about 250 times more orbits a year than > Mercury. The orbiting time of the binary pulsar is less than eight > hours, which can be compared with the one month our moon takes to orbit > the earth. > > A very important property of the new pulsar is that its pulse period, > the time between two beacon sweeps (0.05903 see) has proved to be > extremely stable, as opposed to what applies to many other pulsars. The > pulsar's pulse period increases by less than 5% during 1 million years. > This means that the pulsar can be used as a clock which for precision > can compete with the best atomic clocks, This is a very useful feature > when studying the characteristics of the system. > > The very stable pulse period is in fact a mean of the pulse period > observed on earth over the time of one orbit of the pulsar system. The > observed period actually varies by several tens of microseconds, i.e. by > an amount that is much greater than the variation in the mean value. > This is a Doppler effect, and led to the conclusion that the observed > pulsar moves in a periodic orbit, meaning that it must have a companion. > As the pulsar approaches the earth, the pulses reach the earth more > frequently; as it recedes they arrive less frequently. From the > variation in pulse period, conclusions can be drawn about the pulsar's > speed in its orbit and other important features of the system. > Demonstration of gravitational waves > > A very important observation was made when the system had been followed > for some years. This followed theoretical predictions made shortly after > the original discovery of the pulsar. It was found that the orbit period > is declining: the two astronomical bodies are rotating faster and faster > about each other in an increasingly tight orbit. The change is very > small. It corresponds to a reduction of the orbit period by about 75 > millionths of a second per year, but, through observation over > sufficient time, it is nevertheless fully measurable. This change was > presumed to occur because the system is emitting energy in the form of > gravitational waves in accordance with what Einstein in 1916 predicted > should happen to masses moving relatively to each other. According to > the latest data, the theoretically calculated value from the relativity > theory agrees to within about one half of a percent with the observed > value. The first report of this effect was made by Taylor and co-workers > at the end of 1978, four years after the discovery of the binary pulsar > was reported. > > The good agreement between the observed value and the theoretically > calculated value of the orbital path can be seen as an indirect proof of > the existence of gravitational waves. We will probably have to wait > until next century for a direct demonstration of their existence. Many > long-term projects have been started for making direct observations of > gravitational waves impinging upon the earth. The radiation emitted by > the binary pulsar is too weak to be observed on the earth with existing > techniques. However, perhaps the violent perturbations of matter that > take place when the two astronomical bodies in a binary star (or a > binary pulsar) approach each other so closely that they fall into each > other may give rise to gravitational waves that could be observed here. > It is also hoped to be able to observe many other violent events in the > universe. Gravitational wave astronomy is the latest, as yet unproven, > branch of observational astronomy, where neutrino astronomy is the most > direct predecessor. Gravitational wave astronomy would then be the first > observational technique for which the basic principle was first tested > in an astrophysical context. All earlier observational techniques in > astronomy have been based on physical phenomena which first became known > in a terrestrial connection. Both received a Nobel for discovering of the famous binary pulsar, just that. 1) Gravitational waves have been never detected. Everything about pulsar is about indirect tests. 2) Last high precision observations reveals that binary pulsar is better described by non-geometrical theory of gravity which gives the same prediction than GR more a 1% excess cannot be explained using GR. -- http://www.canonicalscience.org/ |