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swansont

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Everything posted by swansont

  1. They are stationary in a rotating coordinate system, so I think all you have to do is account for the Sagnac effect.
  2. Well, there's also the Vessot experiment with a Hydrogen maser in a rocket, and the Pound-Rebka experiment, which was gravitational redshift. Just off the top of my head. Satellites exist in geosynchronous orbit, too (not sure if the Japanese Quasi-Zenith system is in operation yet, but I imagine telecom satellites all have clocks aboard these days), Galileo will be at a different altitude than GPS, and they've already tested a few satellites, and then there are LEO objects, too. Clocks were to have gone on the ISS via NASA (funding was cut), and the ESA program to do so is still in place AFAIK. So there's plenty of corroboration and further opportunity to measure all this. I predict it will work, relativity-wise, and that almost nobody will be surprised about that. There are reams of time-transfer data from standards labs that nobody bothers to write up because relativity is so well-established that it's simply not worthwhile to do a "relativity confirmed yet again" paper that nobody will publish because it's so blinking far from the cutting edge of physics. You seem to be upset because I don't wish to tilt at your windmills. Sorry, but that's not how it works. You don't get to define the problems I work on, and that I have a choice does not make it a religion. "Relativity doesn't give me a warm, fuzzy feeling" simply isn't a motivation for me, and all you're doing is trying to engage in rhetorical games in order to discredit a scientific theory. Only contradictory evidence can do that.
  3. OK, so look at Ptolemy vs Copernicus. Same answer. The geocentric model isn't invalid. It is equivalent; all you have to do is transform your coordinate systems. The heliocentric model is used and accepted as truth because it's simpler and consistent with other observations (gravity) that have no direct connection with orbital mechanics. But geocentrism was only discarded when the more complete heliocentric model was there to replace it. If you are going to lean on geo vs helio models as examples, you should know that it is not enough to rail on about some perceived problem with SR; to discard it requires some theory that explains what SR explains, and something more, be it extra explanations or simplicity.
  4. But I explained why it's utter crap, rather than stop with a dogmatic statement. You, on the other hand, haven't posted any evidence to the contrary (unless I missed something). It's all about burden of proof.
  5. Actually it was "They couldn't hit an elephant at this distance." General John Sedgwick, Battle of Spotsylvania. Not his final words, and not cut off, though it makes for a good story. He died shortly after uttering them. http://www.civilwarhome.com/sedgwickdeath.htm
  6. We've had several discussions on anomalous dispersion. I suggest availing one's self of the search function.
  7. No, really, it's not very in-depth. There's very little real science described, and several mistakes (e.g. insisting that it's instantaneous communication). There's a limit to how well you can describe the science using macroscopic analogies and philosophical comparisons with other phenomena.
  8. Actually two scenarios are described, since background radiation is a continuum and lasers are generally in a very narrow frequency band. An atom at rest will start moving once it scatters a photon, just as any collision would. The laser detuning issues are more geared toward specific manipulation of atoms; you can get them to do some pretty interesting things under specific conditions (like the Bose-Einstein condensate that Rocket Man mentioed) "detuning of the laser with respect to resonance" means that instead of describing the photon with an absolute frequency, which would be some very large number, the frequency is being described relative to some absorption peak, which has a maximum (or resonance) at some value. The absolute frequency in this case, at ~780.24 nm, is around 3.85 x 1014 Hz, which makes it awkward to discuss changes on the level of 1 MHz or so. It's also often experimentally difficult to measure/generate the frequency directly like that, and much easier to set up a laser to be offset from the absorption feature by several MHz. You can tune a laser until a sample of material absorbs the light (and set it up so you are at the peak of that absorption), which tells you that you are on resonance without measuring the exact value. There are some distinct differences in electronics that drive circuitry in various frequency ranges, so frequencies corresponding roughly to radio (MHz), microwave (GHz) millimeter (THz) and visible waves (100's of THz) all have different issues, and generally more difficulty as the frequency gets higher. You also have issues of trying to change the frequency of light by those various amounts. So mixing in a MHz-sized signal is a lot easier than directly creating a precise one in the 100 THz range.
  9. Ummm, those are simple terms. Resonance, feedback. You'll have to be a little more specific about what you don't understand, because I don't have the time to start at physics 101 and go from there. Photons carry momentum. So scattering photons (absorb from one direction, ejecting them symmetrically) exerts a force (radiation pressure) on atoms. Their ability to absorb atoms, or the rate at which they absorb them, depends on the response curve (absorption vs wavelength). As I explained, you can either slow atoms or speed them up (cool or heat) depending on the original motion of the atoms and the detuning of the laser with respect to resonance.
  10. I have to protest. I can excuse typos and legitmate spelling errors, but unless you are actually posting from your phone, there is no freaking excuse for "texting" instead of typing out words. This isn't a chat room, and you're not sitting at the kids' table. Please act appropriately.
  11. http://mathworld.wolfram.com/SkewLines.html (Markup tag topology error. You have a parenthesis in your url.)
  12. You don't have to restrict the photons to two dimensions, just the perception of them. So, what would a photon "look like" if you could only sample them in 2-D.
  13. And to continue Sisyphus's answer, the reason for the locking is that the tidal deformations do not lie along the axis between the respect center of masses, so there are torques exerted that allow angular momentum transfer (a force along the axis would not allow this). So over time the moon lost rotational angular momentum and now has one side — the more massive side — facing us, and only rotates once per orbit.
  14. swansont

    The Secret

    I'd guess that "the secret" is how to scam people out of $5. "Make a movie," it will say, "and charge folks $5 to watch it. The end."
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