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How haven't we managed to blow up Earth by using particle accelerators?

  1. Oct 7, 2012 #1
    From what I've read, particle accelerators accelerate particles to near the speed of light. As the speed of an object approaches the speed of light, the mass approaches infinite. By that time, that particle is like a wrecking ball. The force required to slow that particle down is almost infinite as well. So that object then can go through pretty much anything. How has that not caused destruction of Earth? Is it just that the momentum just does not transfer?

    This is coming from what I have learned so far about special and general relativity in my sophomore level physics class.
     
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  3. Oct 7, 2012 #2

    ghwellsjr

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    You can't get more energy out of the particles than what the accelerators put in to them and they are extremely inefficient. If you want to blow up the Earth, you'd never do it by such an inefficient means, don't you think?
     
  4. Oct 7, 2012 #3
    Oh, yes, haven't thought about it that way.
     
  5. Oct 7, 2012 #4

    phinds

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    When you take something that is REALLY REALLY tiny and increase its mass by many orders of magnitude, you end up with something that is REALLY tiny. Why would you expect something REALLTY tiny to blow up the world?
     
  6. Oct 7, 2012 #5
    You are right, after putting in some real numbers, the numbers are not that impressive.
     
  7. Oct 7, 2012 #6

    HallsofIvy

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    But we are still working on it!
     
  8. Oct 8, 2012 #7
    Today, gold nuclei. Tomorrow, the world! HAHAHAHAHA! <evil laughter>
     
  9. Oct 8, 2012 #8

    mfb

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    I think the numbers are impressive - but on a laboratory scale, not on an earth-destruction scale. The LHC can store beams with an energy of ~250 MJ, that is 1/4 of the energy of a launching Boeing 747 - stored in 0.6 nanograms of protons (the mass of 7 human red blood cells according to WolframAlpha).
     
  10. Oct 8, 2012 #9
    Cosmic rays particles are more powerful than the ones generated in accelerators and they haven't destroyed Earth yet.
     
  11. Oct 8, 2012 #10

    PAllen

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    yes, the most energetic cosmic rays have the kinetic energy of a professionally thrown fastball in baseball stored in 1 proton!
     
  12. Oct 9, 2012 #11
    I thought the concept of relativistic mass were archaic...
     
  13. Oct 9, 2012 #12

    Drakkith

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    It is. But so is Phinds. He went to dig up his bone and I had to go wake him up and help him finish two and a half minutes later. Turns out he buried a dinosaur bone back in his teen years and had just remembered where it was.
     
  14. Oct 9, 2012 #13

    phinds

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    :rofl:
     
  15. Oct 9, 2012 #14

    PeterDonis

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    Somewhat off topic, but numbers please? It looks to me like you're off by either several or many orders of magnitude, depending on whether "the energy of a launching Boeing 747" is supposed to be the kinetic energy of the plane, the total energy stored in its fuel, or the total energy (including rest energy) of the plane and its fuel.
     
  16. Oct 10, 2012 #15

    Maximum takeoff weight of various models varies from 3.33 *10^5 to 4.42*10^5 kg(wikipedia) and takeoffspeed varies from 160 to 180 knots = 82.3 to 92.6 m/s. Kinetic energy will be from 1.13 to 1.89 GJ, wich is more than the 1GJ that is 4 times the beam energy but this isn't even a single order of magnitude off.
     
  17. Oct 10, 2012 #16

    mfb

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    Thanks willem2. Indeed, I should have specified "kinetic energy", and I used the lower numbers.
    250 MJ are on the lower side, too: Max number of protons was 2.2124*10^14 in beam 1 and 2.1932*10^14 in beam 2 (Fill 3034), all with 4 TeV. This corresponds to 282.3MJ or 1/4 of 1.13GJ. And there we are...
     
    Last edited: Oct 10, 2012
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