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Essay:Rebuttal to Counterexamples to Relativity (view source)
Revision as of 02:46, September 7, 2012
, 02:46, September 7, 2012Add some more, keep it up to date with the other page.
Unlike most essay pages, anyone is welcome to contribute. We ask that you abide by the usual guidelines—do not remove non-vandal, non-parody, non-libelous material without discussing it first on the talk page, or explaining after-the-fact for serious problems.
Unlike most essay pages, anyone is welcome to contribute. We ask that you abide by the usual guidelines—do not remove non-vandal, non-parody, non-libelous material without discussing it first on the talk page, or explaining after-the-fact for serious problems.
#''Despite wasting millions of taxpayer dollars searching for gravity waves predicted by the theory, none has ever been found. Sound like global warming?''
#:True, the ''direct'' searches for gravitational waves have not yet yielded any clear results, though indirect observations have been made (the Hulse/Taylor observations.) Before people dismiss indirect observations, recall that no one has ever seen an electron.
#:The Earth-based LIGO detectors have, so far, not detected any unambiguous gravitational wave signatures from such events as a black-hole merger. It is barely sensitive enough to find such things in the Milky Way or very nearby galaxies. It is being upgraded in a plan that should complete in 2014. It is hoped that, after the upgrade, it will be able to see these events clearly and unambiguously.
#:The space-based LISA detectors have not been built yet, and the original proposal has been scrapped because of budgetary problems. A new version, called "eLISA" has been proposed, and should be sensitive to events as far away as redshift 15.
#:Whether these experiments are a good use of money is another question, one that has no bearing on whether relativity is correct.
#::The objection has been raised that the experiments should not have been funded if scientists were going to ignore negative results.
#:::The results are only partly negative. The scientists knew all along that a certain amount of luck would be involved in finding a sufficiently strong signal within the time frame of the experiment. The failure so far does not mean that black-hole mergers do not emit gravitational waves; just that they haven't been lucky enough to find them. They will continue to search.
#:'''Update:''' Another, much more commonplace observation of gravitational wave emission has neen reported<ref>http://www.bbc.co.uk/news/science-environment-19408363 BBC article</ref>. The article suggests that, since it shows detectable gravitational waves are more common than previously thought, there is optimism that the eLISA detector, when completed, might find one source per week.
#:This has nothing to do with global warming.
#''The orbital radius of the Moon's orbit is increasing, contrary to what Relativity predicts''.
#''The orbital radius of the Moon's orbit is increasing, contrary to what Relativity predicts''.
#:This could be a counterexample to both GR and Newtonian gravity--in both, the radius is defined in terms of conserved quantities.
#:This could be a counterexample to both GR and Newtonian gravity--in both, the radius is defined in terms of conserved quantities.
#''Subatomic particles have a speed observed to be faster than the speed of light, which contradicts a fundamental assumption of Relativity. The Italian lab that "shocked the scientific world" has announced more precise results, confirming their previous announcement''.
#''Subatomic particles have a speed observed to be faster than the speed of light, which contradicts a fundamental assumption of Relativity. The Italian lab that "shocked the scientific world" has announced more precise results, confirming their previous announcement''.
#:This is an interesting observation. The world's best scientific minds are looking into it. That relativity is incorrect is not being taken seriously as a possible explanation.
#:This is an interesting observation. The world's best scientific minds are looking into it. That relativity is incorrect is not being taken seriously as a possible explanation.
#:'''Update:''' The problem seems to have been caused by a faulty cable connection between a computer and a GPS unit. When the connection was repaired, the travel time increased by 60 nanoseconds, which had been the amount of the anomaly <ref>http://www.cbc.ca/news/world/story/2012/02/22/technology-faster-than-light-neutrinos.html</ref> <ref>http://www.foxnews.com/scitech/2012/02/22/loose-wire-led-to-stunning-faster-than-light-particle-finding/?intcmp=features</ref>.
#:'''Update:''' The problem seems to have been caused by a faulty cable connection between a computer and a GPS unit. When the connection was repaired, the travel time increased by 60 nanoseconds, which had been the amount of the anomaly <ref>http://www.cbc.ca/news/world/story/2012/02/22/technology-faster-than-light-neutrinos.html</ref> <ref>http://www.foxnews.com/scitech/2012/02/22/loose-wire-led-to-stunning-faster-than-light-particle-finding/?intcmp=features</ref>. The claims of faster-than-light neutrinos have now been refuted very thoroughly<ref>http://news.sciencemag.org/scienceinsider/2012/02/breaking-news-error-undoes-faster.html</ref><ref>http://news.sciencemag.org/scienceinsider/2012/06/once-again-physicists-debunk.html</ref>.
#:The objection has been raised that a recent news report from the BBC ("now we are 100% sure that the speed of light is the speed of neutrinos") is also contradictory, since neutrinos have mass and are therefore forbidden by relativity to travel at exactly the speed of light. Since the neutrino energies were 17GeV, and the current estimate for the neutrino mass is about 0.25eV, the deviation from the speed of light would be about 1 part in 10<sup>22</sup>. This means that the neutrinos would arrive at the detector about .26x10<sup>-24</sup> seconds (.26 yoctoseconds) later than the speed of light itself. This is one quarter of a billionth of a femtosecond, or about .26x10<sup>-15</sup> of a nanosecond. The accuracy of the GPS units and cesium clocks used in the measurement is greater than a nanosecond, so the discrepancy cannot possibly be detected. It is unfortunate that the claim "the speed of light is the speed of neutrinos" was taken so literally.
#:The objection has been raised that a recent news report from the BBC ("now we are 100% sure that the speed of light is the speed of neutrinos") is also contradictory, since neutrinos have mass and are therefore forbidden by relativity to travel at exactly the speed of light. Since the neutrino energies were 17GeV, and the current estimate for the neutrino mass is about 0.25eV, the deviation from the speed of light would be about 1 part in 10<sup>22</sup>. This means that the neutrinos would arrive at the detector about .26x10<sup>-24</sup> seconds (.26 yoctoseconds) later than the speed of light itself. This is one quarter of a billionth of a femtosecond, or about .26x10<sup>-15</sup> of a nanosecond. The accuracy of the GPS units and cesium clocks used in the measurement is greater than a nanosecond, so the discrepancy cannot possibly be detected. It is unfortunate that the claim "the speed of light is the speed of neutrinos" was taken so literally.
#''Anomalies in the locations of spacecraft that have flown by Earth ("flybys").''
#''Anomalies in the locations of spacecraft that have flown by Earth ("flybys").''
#''Relativity breaks down if a solenoid is traveling at or near the speed of light.''
#''Relativity breaks down if a solenoid is traveling at or near the speed of light.''
#:The equations of electrodynamics (Maxwell's equations), and their connection with relativity, are well known. Hundreds of electrodynamics textbooks cover this subject. The equations are correct at all realizable speeds, even relativistic (''near'' the speed of light) speeds. (Maxwell's equations are said to be the only equations from classical physics that did not need to be modified for relativity.) The equations correctly describe the behavior of magnets (this is presumably what was meant by "solenoids"), charges, and electric and magnetic fields, even at speeds near the speed of light. Of course the equations don't work ''at'' the speed of light. The cited article never discussed speeds ''near'' the speed of light, only ''at'' the speed of light. The questioner was rightly taken to task for his physically unrealizable assumption.
#:The equations of electrodynamics (Maxwell's equations), and their connection with relativity, are well known. Hundreds of electrodynamics textbooks cover this subject. The equations are correct at all realizable speeds, even relativistic (''near'' the speed of light) speeds. (Maxwell's equations are said to be the only equations from classical physics that did not need to be modified for relativity.) The equations correctly describe the behavior of magnets (this is presumably what was meant by "solenoids"), charges, and electric and magnetic fields, even at speeds near the speed of light. Of course the equations don't work ''at'' the speed of light. The cited article never discussed speeds ''near'' the speed of light, only ''at'' the speed of light. The questioner was rightly taken to task for his physically unrealizable assumption.
#''General Relativity predicts how the gravitational fields of the Sun and Moon generate ocean tides. However, in the summer of 2009, tides along the East Coast of the United States were higher than expected.''
#:This one is utterly absurd. The calculation of the gravity of the Sun and Moon in producing tides has been known for hundreds of years, explained by Newtonian gravity. The effect of relativity on this is microscopic.
#:
#:The cited article is about the many things affecting the gross behavior of tides. Keep in mind that the factors affecting the tides involve a lot of hard-to-precisely-quantify things such as wind and ocean currents, and the melting of glaciers. As an example of how imprecise things are, the Atlantic and Pacific Oceans differ in mean height by about 8 inches at the Panama Canal, and the tides are about 20 feet on the Pacific side and 1 foot on the Atlantic side. As another example, tides in the Bay of Fundy are as high as 53 feet. Tides are not a simple calculation from Newtonian or Einsteinian mechanics. The difference between Newtonian gravitation and Einsteinian gravitation is utterly insignificant in comparison to these gross effects.
#''During the gravity assists from Earth, both the Galileo spacecraft and the Near Earth Asteroid Rendezvous (NEAR) spacecraft experienced a change in velocity different than that predicted by General Relativity.''
#:Saying that, every time someone finds some phenomenon that is puzzling, that shows that relativity is wrong, is not a convincing way to do science. The cited paper is about unexpected behavior of some spacecraft as they use "gravity assists" in near-Earth flybys. The hypothesized causes involve errors in the mathematical models to calculate such effects as relativistic effects (the detailed calculation of them, not the question of whether they exist), tidal effects, Earth radiation pressure, or atmospheric drag. The paper suggests that most of those can be ruled out, though there could be round-off and integration errors, or errors in the spherical harmonic representation of Earth's gravity field.
#''The supermassive black hole within the Andromeda galaxy puzzled researchers by increasing in brightness by a factor of 100 in 2006.''
#:This item is about unexpected behavior of the supermassive black holes at the centers of many galaxies. Black holes are a prediction of relativity. The fact that people are still learning new things about them is hardly surprising.
#:
#:The cited article never mentions relativity or the possibility that relativity is wrong. In fact, the entire discussion is in the context of black holes. The second study was about a black hole at the center of a galaxy apparently wandering out of place. The hypothesis is that a merger of two galaxies was involved, and "the theoretical prediction is that when two black holes merge, the newly combined black hole receives a 'kick' due to the emission of gravitational waves ..." Gravitational waves are, of course, a specific prediction of general relativity.
== References ==
== References ==