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swansont

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Everything posted by swansont

  1. Surely you don't mean geostationary here (it is also mistakenly used in the OP) — this is the general orbit equation one can derive by setting the centripetal force equal to the gravitational force. A geostationary orbit has the added requirements that the orbital period be a day and that the orbit be equatorial. i.e. there is only one solution for r for a geostationary orbit.
  2. Only if it helps you figure out where you are wrong. Any model that is not using a rigid object will likely have the problem that has plagued your examples. Once the object is free to move relative to another part of itself, you cannot describe length and time with a single reference frame. A wheel or track moves relative to the body of a car, so an observer (which includes a speedometer) in the car will see it length-contract. A revolution will not be the same length as when measured in the rest frame. The common crank response is to come up with a different, more complicated example, rather than address the flaw in the simple model. Please stop giving crank responses.
  3. Once you work the numbers it's obvious that a circular track is assumed, even though tracks are generally not circular. Bad question in that regard, if that information wasn't explicitly given.
  4. Can you make out footprints with Google maps, or the equivalent, which use airplanes vs satellites? The laughable thing here is that the "coverup" demanded requires more advanced capability than the original landings.
  5. The post office isn't supported by taxes, other than the government paying them for things like free mail for the blind and for overseas voting, and for free mail from congressmen (franking) i.e. the government is a customer and pays for certain services. They haven't gotten operating appropriations for quite some time (1971, I think), when they stopped being a government department. They even show a profit on occasion. When they start losing money, the raise the price of stamps. http://usgovinfo.about.com/b/2008/02/12/postal-service-turns-a-profit-in-q1.htm Compare the quality of the US postal service to foreign counterparts. A letter takes 2 or 3 days to go cross country - anywhere, as opposed to weeks in some places. They're pretty good, for all our complaining to the contrary.
  6. The track is moving with respect to the head. The separation of the track marks changes with speed, due to length contraction. Every example you have come up with so far has this relative motion, which you ignore. Proof by repeated assertion is invalid.
  7. This is a strawman representation of the situation, as well as an appeal to ridicule. Please refrain from arguments based on logical fallacies. ——— The basic notion of space being a propagation medium raises the questions about the original aether. There are implications of the hypothesis, and if you purport to do science, you have to go out and test them. So if space is full of "something," through which light propagates, are we at rest with respect to it or moving?
  8. The "linear coefficients" including a possible - sign, which has certain ramifications. But probably beyond the scope of discussion here. Merged post follows: Consecutive posts merged No, the superposition has actual consequences — the states can interfere. An ensemble in a linear superposition of states is not simply a mixture of particles with half in one state and half in another. http://electron6.phys.utk.edu/QM1/modules/m5/interference.htm This has implications on what results one can see, and these can be (and have been) measured.
  9. No, this is wrong. Speedometers generally do NOT measure proper velocity. Your example is flawed. You can't treat the man as being in a single frame of reference for this example. The legs are moving with respect to the man's head, and you would have to take length contraction effects into account, which you haven't done.
  10. Because that's the way it is in quantum mechanics. When a system is in a superposition of states, it behaves like it is in both states at once. It isn't in just one state until you actually measure it to be in that state.
  11. Not that I am aware. But roads often have markers that would allow one to attempt this kind of measurement, so I am happy to concede that this type of measurement is possible. But I agree, the claim that standard speedometers measure "proper velocity" has not been supported and has been shown to be wrong.
  12. This behavior is seen ONLY in a collective system. There is nothing "fundamental" (as used in this context) about it.
  13. I don't know if this is an aside or follows directly, but one should note that these "death panels" already exist. They are comprised of the managers at whatever insurance company sold you your policy.
  14. A speedometer that measured passage of the trees/markers placed at regular intervals (as described earlier) would do this, if it were calibrated to the rest frame distance of the trees. i.e. your speed would be measured in trees-per-second, and converted to proper speed by knowing the rest frame distance between the trees. However, this is not how most speedometers are configured, and it would not be a true speedometer, since it is measuring this contrived "proper speed." It would be a "properspeed"-ometer. The obvious followup is: why would one bother to do this?
  15. Yes, and … ? "the hole decays into a spinon and a holon" The hole. i.e. the quasiparticle, which is a description of the absence of an electron, displays this behavior. Not the free electron.
  16. No, right answer. From your own source (emphasis added): "Under the worst of circumstances, the report said, the government's maximum exposure could total nearly $24 trillion … Much of the government assistance is backed by collateral and Barofsky's $23.7 trillion estimate represents the gross, not net, exposure that the government could face." You want to try again?
  17. By that metric, then, most government programs are failures. In fact, I think by that metric, all government programs are failures. I imagine you can find some aspect of society that does not benefit by any randomly chosen government program. Which pretty much makes it a useless metric for defining success. ——— Despite the anecdotes presented, the actual results thus far have been better: http://blogs.wsj.com/environmentalcapital/2009/08/05/cash-for-clunkers-an-expensive-environmental-fix/
  18. This is condensed matter physics — it's collective behavior of the electron and its surroundings (i.e. in a wire) that is being treated as a quasi-particle. This is not describing a bare electron.
  19. Why does it need to? That seems to be a contrived objection. Is that a problem the program promised to address? Because it's a strawman argument, since the goods aren't destroyed. The cars, except for the engine, are available as parts. If they get destroyed after six months of being unsold, how much of a market was there for them? New product, representing a larger increase in value of material, has been sold. Merged post follows: Consecutive posts merged If they were waiting, then they were not "in the market" to get a new car. If they were going to buy the new or used car anyway, they have not reduced the existing supply of used cars since they did not buy a used car; all you can say is that they did not add to the supply of used car by not trading one in. Bringing in the housing market and debt is a red herring. You have provided absolutely nothing to back that statement up. Stop it.
  20. The electron is not divided into charge and spin — the "quasiparticle" term refers to a collective behavior of electron and its surroundings that's being investigated.
  21. Let me clarify what I meant — a car that is traded in under the cash-for-clunkers program was not sitting on the lot at Bob's Beaters, waiting to be sold, it was owned by somebody. Bob has just as many cars on the lot for someone to buy. As for vehicles being sold by their owner, if they were going to then buy a used car, that's a zero-sum game. So again, no effect. They didn't sell their car to someone but neither did they buy a used car. So I'm not buying the argument that this program has removed a whole bunch of cars from the used-car supply. And, as you point out, since the parts other than the engine are stripped and an be sold, that points to an increase in supply of these parts, not a decrease, as claimed by navigator. Merged post follows: Consecutive posts merged Yes and yes. I intentionally try to be difficult — it usually makes the fact content of posts go up. And I had hoped for something more substantial than a few snippets in an NPR piece. "Chameides calculates that if you trade in an 18 mpg clunker for a 22 mpg new car (22 miles per gallon is the minimum mileage allowed for a new car under the program), it would take five and a half years of typical driving to offset the new car's carbon footprint. With trucks, it might take eight or nine years, he says." So, for cars, the worst-case scenario is 5.5 years to break-even for the carbon fooprint. Someone who buys a Prius gets break-even in less than 1.5 years (since 18 mpg < 20 mpg used in the story). Which means "buying a used car will reduce your carbon footprint compared to buying new" is only true under a limited set of circumstances, and not generally the case.
  22. A reference would be nice. And what are these numbers. Reference? No existing used cars were destroyed (i.e. used cars for sale, on a lot somewhere), so how exactly did the supply drop? And since people tend to buy used cars more often in a recession, this program has had the effect of reducing demand for used cars, thus easing any pricing pressure on them and making them more affordable. Decent goods? What part of "clunker" is giving you trouble here? We're talking about cars that got less than 18 mpg and were worth less than $4500 (otherwise you'd just trade in your car).
  23. Yes, they do (to the latter) — just barely. http://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/apollosites.html Also, check this out http://www.technologyreview.com/blog/arxiv/23205/ Faking that level of detail would be pretty impressive.
  24. If the other scientist had not yet made a measurement, allowing the particle to still be in a superposition, they would have to communicate this to you somehow. Which would require normal communication speed.
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