How I Learned to Stop Worrying and Love the Black Hole

Discussion in 'Science' started by Goth, Sep 14, 2008.

  1. Goth

    Goth Grumpy Member

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    If the centre-of-mass energy of two colliding elementary particles (a maximum of 14 TeV for pp collisions in the Large Hadron Collider) reaches the Planck scale, ED, and their impact parameter, b, is smaller than the corresponding Schwarzschild radius, RH, then a black hole will indeed be produced. However, the energy corresponding to the Planck scale, EPl ∼ 10 28 eV, is a lot of energy, if you’re an experimental physicist. Such energies are entirely outside the reach of the experimental physicist - so, surely, generation of microscopic black holes (hereafter, µBH) at the Large Hadron Collider (LHC) has got to be impossible - doesn’t it?

    According to the Standard Model of Particle Physics, µBH generation in a
    particle collider is indeed impossible at the TeV-scale energies associated with the current generation of high energy experimental particle physics endeavours, such as the LHC. The much-publicised speculations regarding the possibility of µBH formation at the LHC are based on speculative hypotheses derived from theoretical models of cosmology and particle physics beyond the standard model (“new physics”).

    Certain models put forward some years ago by theoretical physicists offer a
    seemingly neat and efficient lead into answering the questions, such as those of the heirarchy problem, of interest to particle physicists, and involve the existence of higher spatial dimensions.

    The novelty of these higher-dimensional models lie in the fact that it is no longer necessary to assume that these dimensions are of sizes close to the Planck length ( ∼ 10− 35 m). Rather, large extra dimensions could be as large as around a millimetre, if we suppose that the ‘fields of matter’ - those fields of relevance to electroweak interactions and QCD, for example - ‘live’ in the 3+1 dimensional hypersurface of our 3-brane - our familiar 3+1 dimensional world - and that only the gravitational field can interact across the higher-dimensional universe.

    Experiments involving the direct measurement of Newtonian gravity put upper bounds on the size of extra dimensions to a value of less than a few hundred microns. Under such an approach, the traditional Planck scale, corresponding to EPl ∼ 10 28 eV, is no more than an effective scale and the real fundamental Planck scale in D dimensions is given by ED = (E2 Pl /VD
    −4 ) 1/(D −2) , where VD −4 is the volume associated with the D − 4 extra dimensions. In 10 dimensions, with radii associated with the extra dimensions of the Fermi scale, we find ED ∼ TeV.

    Actually, screw this. I'll just upload the original LaTeX version and you can go and read that.

    Enjoy.

    (As usual, comments are encouraged, as is pointing out typos, etc.)
     
  2. knowsfords

    knowsfords Member

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    *Rides a particle accelerator like a bull*
     
  3. Chucky1752

    Chucky1752 Member

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    Ok I did Black Holes in physics ... but from what I learned then, Black Holes pretty much keep existing and crushing things but get larger over time.

    Wouldn't a micro black hole jsut start absorbing things ... excuse my ignorance, but they can't exactly get filled up can they?
     
  4. ewok85

    ewok85 Member

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    The twisted irony here is that the LHC will most probably be able to give experimental evidence that supports one model or the other - but saying that to some folks is like saying "well if it destorys the whole earth then I guess we can safely say the standard model was lacking in some places" :lol:

    First you need to remember that all that we "know" about Black holes is based around very complex theories. The sort of black holes that is talked about is usually massive things that have come from the collapse of stars 20 times the size of our own sun. They do not exist forever, just a very, very, very long time.

    Unless you are "feeding" a micro-blackhole more than its losing its just going to fizzle out, and if you do the maths we are talking about a fair amount of radiation and extremely short amounts of time.
     
    Last edited: Sep 17, 2008
  5. Foliage

    Foliage Member

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    Why don't you read the thread next time?

    edit: read the whole damn single post.
     
  6. Chucky1752

    Chucky1752 Member

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    I read it ... the possiblity and impossibility of such creatures.

    Now answer so I can explain to others.
     
  7. Foliage

    Foliage Member

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    No you didn't.

    If they are created they will be small enough that they will decay before they have any chance to do anything.
     
  8. reaqwe

    reaqwe Member

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    i don't understand the whole thing but could someone explain why higher dimensions would be as small as something like planck length? wouldn't a higher dimension encompass all of the 4 existing ones and be at least bigger than what is currently observable (ie. edges of time)? from my understanding only lower dimensions would be as small?
     
  9. Assasinator_2

    Assasinator_2 (Banned or Deleted)

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    On what definitive scale are you ordering dimensions? They cannot be ordered. For example, what makes up/down come before or after left/right?
     
  10. Flecktone

    Flecktone Member

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    ....but you're forgetting that black holes are scary.... they killed Marty McFly....

    I loved that kid; we all loved that kid.
    :Paranoid:

    Long live LHC.
     
    Last edited: Sep 22, 2008
  11. Whisper

    Whisper Member

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    What the hell movies were you watching that had the character Marty McFly in it?
     
  12. Flecktone

    Flecktone Member

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    Back to the Future...

    anyone who can't see parallels between the LHC and the Flux Capacitor does not deserve to be wearing a foil hat.
     
  13. cyrax83

    cyrax83 Member

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    you sir need a good lesson in life.
     
  14. keyblade master

    keyblade master Member

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    :eek::eek::eek::eek:
     
  15. tup

    tup Member

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    oh dear...
     
  16. Foliage

    Foliage Member

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    Anyone want to enlighten us? I have never heard of the name either.
     
  17. OP
    OP
    Goth

    Goth Grumpy Member

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    OMFG, live under a rock, do we !? :p:rolleyes:
     
  18. knowsfords

    knowsfords Member

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    Yeah Whisper, make like a tree... and get outta here!
     
  19. 42below

    42below Member

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    Anyway, someone broke the LHC so no need to worry for a while.

    Laarry some more beer , hurry up:D
     
  20. Whisper

    Whisper Member

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    Sorry I totally screwed up the question.

    It should have been, What the hell movies were you watching that had the character Marty McFly and black holes in it?

    I knew Marty McFly was inb Back to the Future 1, 2 & 3, but in none of them did recall the mention of any black holes.

    Did any of you?
     

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