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Colli
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re: Developing non-inertial navigation devices
Colli   12/13/2012 10:26:02 AM
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So, is it just me, or is this gibberish?

David Brown
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re: Developing non-inertial navigation devices
David Brown   11/14/2012 3:12:44 PM
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I did not mean to be specific about the issues surrounding the combination between relativity and quantum mechanics - I know there are some things that work fine, and some things that have big unanswered questions. I think that is enough detail here (unless you want to go into depth). And I don't consider M-M to be a failure - I can't see how you read that into my posts. It attempted to measure the ether drag - by failing to do so, it succeeded in disproving the ether theory. So it was very much a success. The comments section here is primarily for discussing the article in question - and is therefore the best place for such discussions. I agree that more detailed discussions of QED or relativity would be best moved elsewhere - but I am not sure if there is a worse possible choice than twitter! After all, it is not a discussion for short and concise posts. A more suitable forum might be a newsgroup like sci.physics.relativity

vofptc
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re: Developing non-inertial navigation devices
vofptc   11/14/2012 2:50:03 PM
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I hate to intrude into your friendly exchange and turn the subject of the article into the colloquium on physics that I ran with my students long time ago, but there is a couple of thoughts. Firstly, there are no problems between Relativity (Special and General) and Quantum Mechanics; there are some discrepancies between Classic and Quantum Electrodynamics. Secondly, before call M-M a failure you have to realize what this experiment did prove. You may be surprised by your findings. Anyway, if there will be more discussion on this subject it would be more productive to move it away from this article and into some other media like twitter, and etc...

David Brown
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re: Developing non-inertial navigation devices
David Brown   11/14/2012 11:34:53 AM
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Why would it be interesting? What do you really think it would show? The M-M experiment was designed to confirm that the speed of light is the same in every direction (well, two perpendicular directions). It was made to disprove the theory of "ether" as a physical medium for light waves. It confirmed that the speed of light is independent of direction (and hence there is no ether), to within the margin of experimental error. Later experiments have greatly improved on the accuracy of M-M. All sorts of experiments have further confirmed the theory of relativity in all sorts of circumstances. There are still plenty of open questions in physics, of course - combining relativity and quantum mechanics is the big one, along with questions about the constancy of fundamental constants (such as "c") throughout the history of the universe. But you can be sure that the speed of light measured by M-M experiments will be independent of direction, regardless of where you do the experiment. So taking an M-M experiment into space is as useful as taking a multimeter, a battery, and some resistors just to check that Ohm's law works in orbit.

Theophilus_
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re: Developing non-inertial navigation devices
Theophilus_   11/14/2012 10:48:12 AM
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Maybe the M-M experiment should be performed in a spacecraft orbiting the earth. This would surely be free of vibration. It would be interesting to see the results.

David Brown
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re: Developing non-inertial navigation devices
David Brown   11/14/2012 7:26:37 AM
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Of course the M-M experiment was performed on a non-stationary platform - at the equator you are moving at 463 m/s around the earth, at around 30 km/s around the sun, the solar system is moving at around 200 km/s around the centre of the Milky Way, and the Milky Way is moving at about 300 km/s within the Local Group, and about 500 km/s compared to the cosmic microwave background. The M-M experiment is not suitable for something like an aeroplane (though related experiments were done in balloons in the twenties) - any vibration would mess it up. But there have been huge numbers of different kinds of experiments demonstrating and confirming relativity that have been done in different places, moving at different speeds relative to the earth's surface.

Theophilus_
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re: Developing non-inertial navigation devices
Theophilus_   11/14/2012 2:35:14 AM
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Has anyone ever performed the Michelson-Morley experiment on a non-stationary platform, e.g. in an aeroplane flying at a constant velocity?

David Brown
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re: Developing non-inertial navigation devices
David Brown   11/13/2012 10:07:27 PM
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I'll happily agree that I've not been particularly polite here. I've called it as I see it, rather directly and to-the-point. And you have been very patient at repeating the same arguments. But what do you want me to say? Should I commend you on how politely you regurgitate nonsense? I would /love/ your idea to be true. I fully agree that a non-inertial measurement of velocity from within the moving object would be a revolution. But there are so many obvious flaws that I am surprised anyone thinks this is possible. I have tried to point out some of them, but was met with babble (photons are bosons and therefore have no mass!). If you would like, I can give you an expansive list of the more obvious effects from the inertial effects on photons. But I fully understand if you don't want to communicate any more here. As for the editor of this article, I suspect he (or she) is cringing in a corner and hoping that this whole article will somehow just go away. To him (or her), I'd say that mistakes do happen - but maybe do a bit more reality checking before publishing next time. Mind you, this has been an entertaining article!

vofptc
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re: Developing non-inertial navigation devices
vofptc   11/13/2012 8:01:25 PM
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Every comment that you have made so far demonstrates in-your-face attitude and total lack of knowledge in the area you are trying to explore. This is my final reply on your comments and I hope that the editor will be aware of your inadequacy and behavior that is inappropriate for a subscriber of such professional magazine.

David Brown
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re: Developing non-inertial navigation devices
David Brown   11/13/2012 6:42:09 PM
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The Sagnac effect measures angular rotation - which is acceleration. Acceleration can be measured - that's easy enough. But every experiment on the subject in the last hundred years has conclusively demonstrated that you cannot detect linear velocity like this - it is the whole basis of relativity. And there are vast numbers of completely pointless patents out there. IBM has a patent on faster-than-light travel, and there are dozens of patents on devices for letting you kick your own backside. The EETimes editors should be making use of them for publishing this article - it greatly lowers the website's standing.

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