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Neutrino near black hole

  1. Oct 9, 2011 #1
    how will a neutrino behave near a block hole? neutrino is having small mass. so it should be sucked into it?
     
  2. jcsd
  3. Oct 9, 2011 #2
    We know in order to escape a black hole you have to go >c speed. Neutrinos is a form of dark matter, so probably trillions go through a black hole every second, or the particle can't go through it and go into the black hole.
     
  4. Oct 9, 2011 #3

    Drakkith

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    Neutrino's obey gravity to my knowledge and would be not be able to escape the black hole.
     
  5. Oct 9, 2011 #4

    phinds

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    Uh, WHAT??? I don't know where you got the idea that neutrinos are a form of dark matter, but that is purely a hypothesis and not a favored one. WIMPS are much more likely to be what dark matter is make up of.

    In any event, as drakkith pointed out, they certainly do NOT ... oh, wait a minute. I was about to respond as though you had said that they go through the black hole, but what you actually said was that either they do or they don't. Well, you got me there. It certainly is true that either they do or they don't. In fact they don't.

    EDIT: OK, I'm new to this stuff and had not read the history of the search for dark matter but I see now that neutrinos were once a leading contender so I see where you go the idea. I emphasize "WERE ONCE".
     
    Last edited: Oct 9, 2011
  6. Oct 9, 2011 #5
    I know I was wrong. They barely interact with matter, but they aren't dark matter. What happens to neutrino in a black hole is still unknown because neutrinos interact with gravity as Drakkith said.
     
  7. Oct 9, 2011 #6

    PAllen

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    Well, as long as one is sticking to current mainstream theories there is no question at all. Neutrinos follow timelike worldlines that are nearly light like. If the pass near enough to a black hole horizon, they will orbit it (but probably the orbit will be unstable, leading to: ); if they pass closer than this, they will soon fall through the event horizon (from the neutrino's point of view). They will then reach the singularity pretty quickly, just like light or any other matter. This is all dependent only on spacetime geometry, irrelevant to the way neutrinos interact with matter.

    Note, that for an outside observer, neutrinos passing near the horizon will appear be trapped at the horizion forever, just like light and any other type of matter.

    Nutshell - there is nothing special about the way neutrinos interact with black holes compared to other particles (unless current theories are substantially wrong).
     
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