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Strange

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Everything posted by Strange

  1. Mainly because GR requires things to be smooth and continuous (differentiable) which conflicts with the quantization of QM. More here: http://www.askamathematician.com/2009/12/q-howwhy-are-quantum-mechanics-and-relativity-incompatible/
  2. I think "fabric" is a very misleading analogy. On another forum someone came up with this (I'm sure he won't mind me pinching it): In other words it isn't "space" that is curved (after all, it doesn't exist) it is the lines (geometry) connecting points in space and time that are curved. "Embodies" is an odd choice of word. Even "pervades" would be odd, but perhaps more accurate. The zero point is just a statement of the fact that the minimum energy of empty space is non-zero. And I don't see why this value has any relevance to the big bang theory; it is a purely quantum effect.
  3. That is hardly surprising. That is one reason why YouTube is not considered a reliable source of information. And yet so many people with their "personal" theories seem to rely on it ...
  4. Absolutely. A good strategy is to start by writing the tests and then write the function to be tested. This is a good way to make sure that the specification (you do have a specification, right? ) is complete and consistent. Or, in the (sadly more realistic) case that you don't have a spec, that you understand what you are trying to do.
  5. Don't be ridiculous. I didn't say that. I said that you chose to give up your rights. If you regret that now, then you just have to stop posting here. Worth noting that the development of the Internet was funded by the US Defense Advanced Research Projects Agency so perhaps not as idealistic as you think.
  6. Even if it were a universal right, you voluntarily gave up that right by agreeing to the rules of the forum.
  7. Could it be this? Nostoc commune - A Cyanobacteria (Cyanobacteria Images) Blue-green algae, recognition and eradication (Though I don't know how it got into a lemonade bottle...) Edit: Or Wood Ear Fungus? (but I don't know how that would get into the lemonade either!)
  8. Because they absorb infra-red as well as light.
  9. It WASN'T a spaceship. Read the OP again. It was a bunch of kids. The only thing the bunch of kids could use as mass to change their velocity was some of the kids. Because that is all they had: a bunch of kids. (OK, they could have tried throwing their underwear, but I doubt that would have been very effective.)
  10. Because that is the scenario in the movie/book. Note that they are not thrown out of a spaceship: "no kids were harmed in the creation of this scenario".
  11. No. Not Mercury. And not "appeared from behind the Sun before it should have". Again, here is a simple description of the experiment. Why not read it? Does it mention Mercury? Einstein’s theory of general relativity is tested, May 29, 1919 | EDN
  12. I hope it is (and not a real exercise). Also, note that in the book/film/question, kids are not being thrown from a spaceship, but from a larger group.
  13. Fabrics are dark because they absorb light. The idea is that if they absorb visible light then they may be more likely to absorb UV as well.
  14. To really get the most out of a language like C++, Java, C#, etc you should read up on design patterns. For example: http://www.amazon.com/Design-Patterns-Elements-Reusable-Object-Oriented/dp/0201633612 http://www.headfirstlabs.com/books/hfdp/
  15. I hate to be picky (*) but shouldn't that be hypervalent_bromine (*) You're right. I don't.
  16. Looks like the OP hasn't been back for a while. But Gerard 't Hooft wrote a good guide to the sort of studying you would have to do to reach this goal: http://www.staff.science.uu.nl/~hooft101/theorist.html
  17. Maybe that was Ellington. Unless you mean Subrahmanyan Chandrasekhar.
  18. The words are, inevitably, ambiguous. On the surface of the Earth, a geodesic is equivalent to a straight line in that it is the shortest distance between two points; i.e. part of a great circle. Projected onto a map it may not appear straight. Considered in 3D space it is not straight. The definition in GR is somewhat more complex.
  19. The missing words include "Eddington" and "stars". Here is the briefest (and reasonably accurate) description of the experiment I have found: http://www.edn.com/electronics-blogs/edn-moments/4415308/Einstein-s-theory-of-general-relativity-is-tested--May-29--1919
  20. I stand corrected, yes "Ellington" was a pompous physicist,, my mistake! My irony meter just broke.
  21. Hang on! You mean yours doesn't?
  22. As a concrete example, if you are in free fall you are travelling along a geodesic (the equivalent of a straight line in curved space-time). When you are sitting in your chair, you are (I think) being accelerated along a curved path. [Don't be surprised if someone more knowledgeable says I have got that wrong. I certainly won't be ... ]
  23. It isn't like a force "pushing" the galaxies through space. It is just that the "metric" (crudely, the measurement of distance between things) increases over time. So, over time, things get further apart (without themselves moving).
  24. Also, the clue is in the title: "urban legends"
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