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Analogy of en event horizon

  1. Nov 27, 2013 #1

    I am trying to draw an analogy, which just came with a flash in my mind. Please clarify me, if it is wrong. Kindly note that it is an analogy only.

    An event horizon -- Where the light emitting is not strong enough to go inside the black hole also it cannot go outside the zone and keeps on hovering around.

    If I open a tap water and the water gushing down the basin creates a spherical form. The water neither can flow inside the basin, nor it can go outside.

    Is it this which can be thought of a black hole event horizon?

    Please correct me if I am wrong.

  2. jcsd
  3. Nov 27, 2013 #2


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    I don't follow you there at all. Of course the water can flow down. Why would it not?

    Also, it would not be a spherical form, it would be a circular form.
  4. Nov 27, 2013 #3


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    Also, light readily enters a black hole. The only light that is trapped is light emitted at the horizon in the radial outgoing direction. All other light emitted at or in the horizon reaches the singularity (in the simplest BH). Further, all light heading toward the BH, crosses the horizon and reaches the singularity.
  5. Nov 27, 2013 #4


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    There is another analogy that has drawn significant scientific interest. It is called an acoustic black hole. IIRC one was created not long ago using an Bose-Einstein condensate.
  6. Nov 27, 2013 #5


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  7. Nov 27, 2013 #6
    My question was trying to understand how an event horizon looks like? My analogy of water flowing down is that the light which hovers around the 'event horizon' of a black hole, can that look like the water which forms a border on the basin?
  8. Nov 28, 2013 #7


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    The short answer is ... No.
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