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Matter travelling faster then light inside a black hole

  1. Jul 31, 2008 #1
    hi, i'm most likely the dumbest person around here
    i study electronics, and havent seen anything like this at school,
    but i was doing some own research for a paper (for my physics teacher)
    and i rather got confused when i read some sites
    so my question is :
    is it possible to travel faster then light INSIDE a black hole?

    i get the fact that at the event horizon:
    gravity pull= speed of light, this is the "frozen effect", the light photons force to move away from the black hole and the force drawing them in is equal( like 2 persons pulling a string equally)

    now since as you come closer to the black hole you come closer to the speed of light
    with when you reach the event horizon v=1c

    would it not be logic that beyond the horizon v>1c
    so outside event horizon v<1c
    on top of event horizon v=1c
    beyond the event horizon v>1c

    my question now is, where lies my mistake?(if i made one)

    i'm not trying to be a know-it-all
    its is rather disturbing and hard to grasp how mucht a dimension as time is being influcent by gravity, if someone could explain this to me, i would find it easier to grasp,
    if you want to anwser with formulas, be my guest, i had enough maths in school and i know how to use a search button to understand the formulas myself

    feel free to point out my gaint flaws in my assumption
    after all the only physics i've had so far about this subject were the ones that google showed me
    so please correct me
  2. jcsd
  3. Jul 31, 2008 #2
    The physical speed of light is constant in vacuum everywhere.

    However the coordinate speed of light depends on how you chart spacetime.
  4. Jul 31, 2008 #3
    hmm i understand, but that still leaves me with the question if i throw a brick in a black hole
    and it comes closer to the speed of light as it approaches the event horizon
    and if i understand correctly from what i've read of various sites, the brick would have the speed of light crossing the event horizon
    would the speed not increase further then beyond the event horizon?
    or am i missing a crucial point here?
  5. Jul 31, 2008 #4
    The crucial point you are missing is that an inertial object (such as the brick you mention) does not increase its physical speed, it has no speed by itself. It has only a speed in relation to something else. If you want to track such a relation you have to chart spacetime, and then the relative speed of this brick will depend on what chart you use.
  6. Jul 31, 2008 #5
    and from what i've read on those other sites, spacetime inside the blackhole is distorted beyond comprehend...
    i understand your point now, i'm not even going to bother to even think further upon it,
    it would raise more questions then anwsers for me...
    i'm just going to hand in my report and forget about the enitre case :)
    thank you for your help:)
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