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Talk:Counterexamples to Relativity (view source)
Revision as of 14:52, August 19, 2010
, 14:52, August 19, 2010→Reversion of my edit: Who did the GR calculations? Conservapedia did!
*Intelligent design: The last time a journal editor managed to get an ID paper through peer review, he was forced to resign. The refrain, "No peer reviewed papers on ID" is the strongest (non-scientific) argument against ID, but it's based on [[circular reasoning]].
*Intelligent design: The last time a journal editor managed to get an ID paper through peer review, he was forced to resign. The refrain, "No peer reviewed papers on ID" is the strongest (non-scientific) argument against ID, but it's based on [[circular reasoning]].
Perhaps we need an article on [[Scientific censorship]]. --[[User:Ed Poor|Ed Poor]] <sup>[[User talk:Ed Poor|Talk]]</sup> 13:12, 16 August 2010 (EDT)
Perhaps we need an article on [[Scientific censorship]]. --[[User:Ed Poor|Ed Poor]] <sup>[[User talk:Ed Poor|Talk]]</sup> 13:12, 16 August 2010 (EDT)
My goodness! Andy and RonLar are ''still'' debating the GPS issue? You two clearly enjoy debating each other, and I enjoy reading what you have to say.
As far as the questions above "who did the Relativity calculations?" and "who did the Newtonian calculations?" for GPS, I don't think it's important for the person doing the relativity calculations to have published his work or otherwise made himself known. The fundamental formulas for the GR time dilation effect under discussion are known to nearly all physics graduate students. This isn't to say that GR isn't very complicated, but the number of people who understand it is now ''way'' more than 3. The equation for the relative incremental time dilation/contraction is <math>g/c^2</math> where <math>g</math> is the strength of the gravitational field. Now the rest of the derivation is straightforward. I'll take you through it. In the vicinity of the Earth, we have
::<math>g = \frac{GM}{r^2}</math>
so the dilation is
::<math>\frac{GM}{c^2r^2}</math>
Because the satellites are so high, we have to take into account the change in strength between the receiver and the transmitter, so we have to do an integration:
::<math>\int_{R1}^{R2}\frac{GM}{c^2r^2}\ dr</math>
where <math>R_1</math> and<math>R_2</math> are the radii at the receiving point (6.4E6 meters) and the satellite (20E6 meters). We have G (Newton's constant) equals 6.7E-12, and M (Earth's mass) equals 6E24.
The integral is
::<math>- \frac{GM}{c^2r}\left|\right.^{R_2}_{R_1}</math>
Plugging in the numbers, we get .477E-9, which is about 45 microseconds per day. The special relativity correction due to the speed of motion is about 7 microseconds per day in the opposite direction. The total is about 38 microseconds per day, which is compensated for by adjusting the clock rates. Without this, the ability of GPS devices to show position would drift by about 10 kilometers per day, which would make them useless.
The correctness of these equations is independent of whether the people running the system have gone through the derivation, just as the correctness of Maxwell's equations is independent of whether people using electric motors understand those equations. Scientific theories are not correct or incorrect depending on whether specific people understand them, or the thought processes that went into the design of any particular device.
A final note to Andy: Since you and RonLar are clearly enjoying this debate, and clearly consider each other to be worthy adversaries, I'd suggest that you unblock RonLar's IP address, if indeed it is still blocked. It's the honorable and gentlemanly thing to do. [[User:Simeon|Simeon]] 10:52, 19 August 2010 (EDT)
== Quote mine ==
== Quote mine ==