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Radical Edward

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Everything posted by Radical Edward

  1. well gravity is curvature of spacetime... so. make of that what you will, you can't disentangle the two.
  2. while the bones were hollow, there was a small loss in strength, but it was more than made up for by a loss in mass. They use the same principle as things like tower cranes:
  3. I am convinced that the universe will end on the 31st december 2010, because that is the end of the calendar.
  4. massive objects traveling at c makes no mathematical sense. You just get an equation with a load of infinities in it, meaning it is unphysical.
  5. that isn't really true. There is a decent variation of sizes right through the ocean, but one thing you have to remember is that near the surface, there is a lot more energy, and thus food available because of the sun. There are still massive animals deep down, like giant squid and the kraken.
  6. well it is the minimum mass that a black hole can be. any masses of this size or larger would have to be of sufficient density. As you say though. quantum gravitational effects would most likely be important on this sort of scale anyway, so it could be way out. Also if there are higher spatial dimensions that are bigger than a planck length, it would also be different. I'm just working with what we have to go on at the moment though - I don't want to drag things like string theory and quantum loop gravity in here because they are so speculative. Merged post follows: Consecutive posts merged not really. Black holes are defined by their mass, their charge and their angular momentum. The diameter is exactly related to the mass - this is the equation:
  7. a lot of this depends on the sophistication of the explosives. The body bomb probably would not have done much damage unless there was a lot of it, because it is such a terrible shape, and significantly muffled (by the body it was wrapped around), but if the explosive was carefully shaped, it could cause serious damage and punch a hole in the side of an aircraft.
  8. there are lots of organizations with the same acronym. I wouldn't worry about it too much
  9. basically yes. The analogy I like to use (rather than a balloon expanding) is letting a loaf of bread rise. at the start, the loaf of bread is all nicely compact, but as the yeast starts metabolizing, the bread starts to expand. There are two basic forces at work - the expansion of the bread due to the yeast and the molecular forces of the molecules of the dough, pulling it back together. On average, the expansion wins (over long distances) and any two bits of bread are moving away from one another. On very short distances however (half a millimetre say) the tension of the bread molecules holds the bread together, so you get bubbles. When a bubble forms, some bits of bread will be pulled closer together. how does that work for you?
  10. There is a low mass limit - it is roughly the planck mass. The actual limit is such that the reduced Compton Wavelength (which is the minimum size of the region at which a mass of M can be localised) exceeds half of the Schwarzschild radius. below this mass, there is no physical description of black holes.
  11. you'd need something like thick metal and weld it shut.
  12. it can be. That's why things blow up; because there is too little surface area (in the case of nuclear bombs, intentionally so. In the case of chernobyl or the Demon Core, not so much. One possibility is the use of Radioisotope Thermoelectric Generators: http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator. The problem with nuclear waste is the often very complicated series of waste products. Some are metals, some are metals, some are not, some are solids, liquids or gasses at room temperature (or whatever your operating temperature would be). Then there is the issue of moderation. You do not want to be outputting the same amount of power all the time, and so you can moderate the reaction with control rods (or lower the fuel rods in and out of a moderator), but then as impurities build up, the rates of fission can change dramatically if your initial fuel source is not in equilibrium with all its daugther products. here enters my speculation; I'm not a nuclear physicist. I do not represent any nuclear regulation bodies. Any experiments that you perform on my speculative ideas are your responsibility, and I will not be held liable for any accidental nuclear meltdowns/radiation incidents that you might cause.... Coming up with an "equilibrium source" and using that to just heat things that power a generator (mineral oils are usually used instead of water) might be a possibility - remember boiling temperature is just a function of pressure, so if your system pressure is low enough, then the boiling temperature is lower and you can drive turbines without requiring your source to be hundreds of degrees in temperature.
  13. I guess you mean Autotrophs... An apostrophe is a punctuation mark... this one in fact --> '
  14. One cannot prove scientific theories - they are models of systems after all, and to prove them would require looking at every single system, which is of course impossible. Evidence we can find can support the theory, and even to the point where we are so certain of its truth that it would be ridiculous to think otherwise, but you only need a single verifiable contradiction, and the theory is wrong and may need wholescale changing, or refinement. Theories however can be disproven of course, as many have - such as the lumiferous aether, young earth creationism, phrenology, homeopathy and so on.
  15. wow, almost 6 years since I created this thread now.
  16. you'll also blow a fuse probably as I did when I was drilling... and that other time where I touched the live wire when the switch was on, and that other time when.... (despite me being a physicist, I am dangerous when it comes to DIY, so I don't) What is it you're actually igniting by the way?
  17. exactly. They should implement a system where only the people who want to know about the warning get warned (an opt out system) This way the idiots that think they know better won't get a warning and they will stay on the beach if a tsunami hits. It would certainly breed out some stupidity.
  18. it is 1/sqrt(Mu*Epsilon) Where Mu and Epsilon are the permittivity and permeablity of free space. This is derived from maxwell's equations by taking a couple of the equations and developing the wave equation from them. the detail can be found here: http://en.wikipedia.org/wiki/Electromagnetic_wave_equation but that is the basic answer. Merged post follows: Consecutive posts merged e=mc2 is for rest mass. You'll notice immediately that momentum is missing from that equation, so it can't be right. The full equation for energy wrt mass and momentum is E2=p2c2+m2c4
  19. likewise. The term atheist only exists in the presence of the theistic concept. It would be ridiculous to claim that I am an afnerlist, because fnerl isn't a concept that we have conceived of yet.
  20. I hope the sheer ancientness of my account is preserved in the move.
  21. what happens when galaxies collide? this: just do a google image search for colliding galaxies. Hubble has taken some excellent pictures.
  22. no, Eyes are a basal feature of mammals (the common ancestor to all mammals had eyes) - indeed eyes are basal to the tetrapods. The the last common ancestor to all of the bats would also have had good eyesight. Now not all bats (Chiroptera) have bad eyesight, the Megachiroptera (megabats, including fruit bats) have excellent eyesight, and even better smell. Microchiroptera on the other hand predominantly use echolocation as they chase insects in dark caves. About the eyesight though. as the microchiroptera developed better and better echolocation, their eyesight would degrade as it became less important to their way of life. Operating eyes and the relevant bits of the brain takes a substantial amount of energy, and if the eyes are not even being used to their full extent, that is a waste of resources, and so mutations to the eyes and brain parts reducing them to what they are now would actually be beneficial. regarding humans seeing properly, well it's difficult to say what you would mean by "properly". Many nocturnal birds have much better visual acuity than we do, for example owls.
  23. here's a nice little related article on observed evolution over a 30 year period: http://news.nationalgeographic.com/news/2008/04/080421-lizard-evolution.html
  24. it wouldn't work, because the whole system is a zero sum game. at the end of the day, all the Carbon that you take in will either become a part of you or released. you don't generate carbon, you just release what you take in. so a reduction in the carbon that you release would be perfectly balanced by the carbon that you didn't take in from the environment. The only way to reduce C)2 levels is to sequester carbon and remove it from the biosphere. This was previously done by stuff getting buried and staying underground, but we keep digging it up and burning it. a possible "natural" method might be to grow lots of trees, weight them down (or get wood that waterlogs and sinks) and dump them in the ocean. Or alternatively seed the oceans with chemicals other than carbon that would allow massive quantities of algae to grow, and let it sink.
  25. do bear in mind that being a relativistic equation you should be careful about what you mean by moving and stationary.
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