Changes

#''Despite wasting millions of taxpayer dollars searching for gravity waves predicted by the theory, none has ever been found.  Sound like global warming?''

#''Despite wasting millions of taxpayer dollars searching for gravity waves predicted by the theory, none has ever been found.  Sound like global warming?''

#:This is because the experimental capability to do so doesn't exist.

#: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.

#:It has nothing to do with global warming.

#: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.

#:::"This is because the experimental capability to do so doesn't exist." - if that were true, then were the costly experiments done if relativists were going to ignore the negative results?--[[User:Aschlafly|Andy Schlafly]] 00:56, 26 February 2012 (EST)

#: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.

#: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.

#:::So?  That wouldn't change the fact that this is a counterexample to Relativity.--[[User:Aschlafly|Andy Schlafly]] 00:56, 26 February 2012 (EST)

#::The objection has been raised that this would still be a counterexample to Relativity.

#''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''.

#:::Yes, if it were actually true that the Moon's orbit is undergoing some kind of anomalous perturbation, it would indeed be a disproof of Relativity, Newtonian mechanics, and, in fact, all of physics since Galileo.

<!--#''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 Pioneer anomaly.''

-->#''The Pioneer anomaly.''

#:The "Pioneer anomaly" is the deviation in the motion of the Pioneer 10 and Pioneer 11 spacecraft from their predicted motion, at the distance of Saturn and beyond.  It should be noted that the anomaly is about 1000 times greater than the difference between the classical Newtonian prediction and the prediction of relativity, so this is not a problem with relativity ''per se''; it is more general than that.

#:The "Pioneer anomaly" is the deviation in the motion of the Pioneer 10 and Pioneer 11 spacecraft from their predicted motion, at the distance of Saturn and beyond.  It should be noted that the anomaly is about 1000 times greater than the difference between the classical Newtonian prediction and the prediction of relativity, so this is not a problem with relativity ''per se''; it is more general than that.

#:Calculating the force caused by heat (that is, miniscule amounts of infrared radiation) from the radioactive power source was one of the first effects that was examined.  The anomaly arose when this and other known effects could not fully explain the deviation.

#:Calculating the force caused by heat (that is, miniscule amounts of infrared radiation) from the radioactive power source was one of the first effects that was examined.  The anomaly arose when this and other known effects could not fully explain the deviation.

#:Correct me if I'm wrong, but wasn't it due to the acceleration of various parts of galaxies that accelerated funny that led to dark matter (based on simple Newtonian dynamics)?  

#:Correct me if I'm wrong, but wasn't it due to the acceleration of various parts of galaxies that accelerated funny that led to dark matter (based on simple Newtonian dynamics)?  

#''The acceleration in the expansion of the universe confounds Relativity, and unseen "dark energy" has been invented to try to retrofit observations to the theory.''

#''The acceleration in the expansion of the universe confounds Relativity, and unseen "dark energy" has been invented to try to retrofit observations to the theory.''

#:Uh-oh....the dark energy/cosmological constant argument....That term was added by Einstein after he discovered that his field equations (<math>\mathbf{G}=8\pi \mathbf{T}</math>) predicted that the universe was expanding, contradicting his firm philosophical belief in a static universe. So he inserted <math>\Lambda \mathbf{g}</math> to the LHS so that it would predict a static universe. A few years later, Hubble showed the universe to be expanding, and Einstein called the cosmological constant the worst mistake of his career. So, it sort of had a bad reputation, and people didn't want to seriously consider it, until recent observations have shown the universe's expansion to be accelerating forced them to do so. It could have had a very different history. Einstein could have had that term in the EFE's from the start, and pointed out that it would determine if the universe's expansion was accelerating (or not expanding at all!) and it would take further observation to determine its value.   

#:This is the dark energy/cosmological constant argument. The cosmological constant was added by Einstein after he discovered that his field equations (<math>\mathbf{G}=8\pi \mathbf{T}</math>) predicted that the universe was expanding, contradicting his firm philosophical belief in a static universe. So he inserted <math>\Lambda \mathbf{g}</math> to the LHS so that it would predict a static universe. A few years later, Hubble showed the universe to be expanding, and Einstein called the cosmological constant the worst mistake of his career. So, it sort of had a bad reputation, and people didn't want to seriously consider it, until recent observations have shown the universe's expansion to be accelerating forced them to do so. It could have had a very different history. Einstein could have had that term in the EFE's from the start, and pointed out that it would determine if the universe's expansion was accelerating (or not expanding at all!) and it would take further observation to determine its value.   

#''Increasingly precise measurements of the advance of the perihelion of Mercury show a shift greater than predicted by Relativity, well beyond the margin of error.''

#''Increasingly precise measurements of the advance of the perihelion of Mercury show a shift greater than predicted by Relativity, well beyond the margin of error.''

#:A footnote goes on to say that "In a complicated or contrived series of calculations that most physics majors cannot duplicate even after learning them, the theory of general relativity's fundamental formula, <math>G_{\mu\nu} = 8 \pi K T_{\mu\nu}\,</math>, was conformed to match Mercury's then-observed precession of 5600.0 arc-seconds per century.  Subsequently, however, more sophisticated technology has measured a different value of this precession (5599.7 arc-seconds per century, with a margin of error of only 0.01) ..."

#:A footnote goes on to say that "In a complicated or contrived series of calculations that most physics majors cannot duplicate even after learning them, the theory of general relativity's fundamental formula, <math>G_{\mu\nu} = 8 \pi K T_{\mu\nu}\,</math>, was conformed to match Mercury's then-observed precession of 5600.0 arc-seconds per century.  Subsequently, however, more sophisticated technology has measured a different value of this precession (5599.7 arc-seconds per century, with a margin of error of only 0.01) ..."

#:The topology of wormholes is an interesting topic, widely discussed among theoretical physicists and mathematicians.  There is much speculation about what they would be like (if they could exist at all under quantum gravity), and what kind of "cosmic censorship" or "chronology protection" theorems might make practical time travel impossible.  The nature of these theorems seems to be intertwined with theories of quantum gravity and "grand unification", so the exact form of the "cosmic censorship", if it exists, can't be known until quantum mechanics and relativistic geometry are unified.  It is an exciting field of research.  No one believes that the "cosmic censorship" will take the form of relativity not being a true non-quantum approximation to reality.

#:The topology of wormholes is an interesting topic, widely discussed among theoretical physicists and mathematicians.  There is much speculation about what they would be like (if they could exist at all under quantum gravity), and what kind of "cosmic censorship" or "chronology protection" theorems might make practical time travel impossible.  The nature of these theorems seems to be intertwined with theories of quantum gravity and "grand unification", so the exact form of the "cosmic censorship", if it exists, can't be known until quantum mechanics and relativistic geometry are unified.  It is an exciting field of research.  No one believes that the "cosmic censorship" will take the form of relativity not being a true non-quantum approximation to reality.

#''The theory predicts natural formation of highly ordered (and thus low entropy) black holes despite the increase in entropy required by the Second Law of Thermodynamics.''

#''The theory predicts natural formation of highly ordered (and thus low entropy) black holes despite the increase in entropy required by the Second Law of Thermodynamics.''

#: Since the 70's much works has been done on the subject of black hole thermodynamics <ref>http://adsabs.harvard.edu/abs/1973CMaPh..31..161B</ref><ref>http://arxiv.org/pdf/gr-qc/9307035v1.pdf</ref>, most notably by the Lucasian Professorship of Mathematics at Cambridge [[Stephen Hawking]]. When quantum field theory is added to the analysis of black holes it is found that they do not possess "low entropy" (quite the opposite, in fact) and are consistent with the laws of thermodynamics <ref>http://adsabs.harvard.edu/abs/1973PhRvD...7.2333B</ref>. The [[Counterexamples to Relativity]] article has labelled this work in a footnote as "[c]ontrived explanations", with no explanation for this characterization given.

#:Since the 70's much work has been done on the subject of black hole thermodynamics<ref>http://adsabs.harvard.edu/abs/1973CMaPh..31..161B</ref><ref>http://arxiv.org/pdf/gr-qc/9307035v1.pdf</ref>, most notably by the Lucasian Professorship of Mathematics at Cambridge [[Stephen Hawking]]. When quantum field theory is added to the analysis of black holes it is found that they do not possess "low entropy" (quite the opposite, in fact) and are consistent with the laws of thermodynamics<ref>http://adsabs.harvard.edu/abs/1973PhRvD...7.2333B</ref>. The [[Counterexamples to Relativity]] article has labelled this work in a footnote as "[c]ontrived explanations", with no explanation for this characterization given.

#''Data from the PSR B1913+16 increasingly diverge from predictions of the General Theory of Relativity such that, despite a Nobel Prize in Physics being awarded for early work on this pulsar, no data at all have been released about it for over five years.''

#''Data from the PSR B1913+16 increasingly diverge from predictions of the General Theory of Relativity such that, despite a Nobel Prize in Physics being awarded for early work on this pulsar, no data at all have been released about it for over five years.''

#:Please read the cited paper carefully.  It is a survey of their observations over a 30 year period.  They point out that their data matches general relativity to within 0.2 percent, and is now down in the "noise" of other effects, such as lack of accurate knowledge of just how far away the pulsars are, and lack of accurate knowledge of galactic constants.  As they say in the abstract, "tighter bounds will be difficult to obtain."  The paper, written in 2004, also notes that, because the pulsar beams are slowly tilting out of the line of sight to Earth, "A core component [of the emission] is quite prominent in the data taken in 1980-81, but it faded very significantly between 1980 and 1998 and was nearly gone by 2003."

#:Please read the cited paper carefully.  It is a survey of their observations over a 30 year period.  They point out that their data matches general relativity to within 0.2 percent, and is now down in the "noise" of other effects, such as lack of accurate knowledge of just how far away the pulsars are, and lack of accurate knowledge of galactic constants.  As they say in the abstract, "tighter bounds will be difficult to obtain."  The paper, written in 2004, also notes that, because the pulsar beams are slowly tilting out of the line of sight to Earth, "A core component [of the emission] is quite prominent in the data taken in 1980-81, but it faded very significantly between 1980 and 1998 and was nearly gone by 2003."

#:The reference to the twin paradox suggests that the author thought that the passage of time is some kind of scalar field that should be obtainable as the path integral of a conservative vector field.  It is not.  Passage of time is a property of one's path through spacetime, and is similar to path length.  (In fact, under the Lorentz/Minkowski metric, it is exactly path length.)  Just as two paths from point A to point B on a sheet of paper can have different lengths, the paths of the twins can have different lengths, and hence different elapsed local times.

#:The reference to the twin paradox suggests that the author thought that the passage of time is some kind of scalar field that should be obtainable as the path integral of a conservative vector field.  It is not.  Passage of time is a property of one's path through spacetime, and is similar to path length.  (In fact, under the Lorentz/Minkowski metric, it is exactly path length.)  Just as two paths from point A to point B on a sheet of paper can have different lengths, the paths of the twins can have different lengths, and hence different elapsed local times.

#''The Ehrenfest Paradox: Consider a spinning hoop, where the tangential velocity is near the speed of light. In this case, the circumference (2&pi;R) is length-contracted. However, since R is always perpendicular to the motion, it is not contracted. This leads to an apparent paradox: does the radius of the accelerating hoop equal R, or is it less than R?''

#''The Ehrenfest Paradox: Consider a spinning hoop, where the tangential velocity is near the speed of light. In this case, the circumference (2&pi;R) is length-contracted. However, since R is always perpendicular to the motion, it is not contracted. This leads to an apparent paradox: does the radius of the accelerating hoop equal R, or is it less than R?''

#:(not done yet)

#:The "Ehrenfest paradox" is not an actual paradox.  Non-inertial relativistic motion of solid bodies is quite complicated, involving such concepts as "Born rigidity", "Langevin observers", the "Langevin-Landau-Lifschitz metric", and "quotient manifolds".  In general, the subject is complicated, and has provided physicists with much food for thought.  But it does not disprove relativity.

#''Based on Relativity, Einstein predicted in 1905 that clocks at the Earth's equator would be slower than clocks at the North Pole, due to different velocities; in fact, all clocks at sea level measure time at the same rate, and Relativists made new assumptions about the Earth's shape to justify this contradiction of the theory; they also make the implausible claim that relativistic effects from gravitation precisely offset the effects from differences in velocity.''

#''Based on Relativity, Einstein predicted in 1905 that clocks at the Earth's equator would be slower than clocks at the North Pole, due to different velocities; in fact, all clocks at sea level measure time at the same rate, and Relativists made new assumptions about the Earth's shape to justify this contradiction of the theory; they also make the implausible claim that relativistic effects from gravitation precisely offset the effects from differences in velocity.''

#:The claims of that item are preposterous.  Read the cited paper (or its abstract) carefully.  Einstein's statement that clocks would run slower at the equator, due to time dilation, was correct according to special relativity alone.  What Einstein didn't realize, because he wouldn't discover general relativity for another 10 years, was that the gravitational time shift would offset that.

#:The claims of that item are preposterous.  Read the cited paper (or its abstract) carefully.  Einstein's statement that clocks would run slower at the equator, due to time dilation, was correct according to special relativity alone.  What Einstein didn't realize, because he wouldn't discover general relativity for another 10 years, was that the gravitational time shift would offset that.