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Blac hole question

  • 26-12-2008 3:55pm
    #1
    Registered Users, Registered Users 2 Posts: 6,905 ✭✭✭


    whenever the show them in tv shows,movies or documentaries ive never understood the appearence of the event horison.

    Because they are so dence the attract all light and matter in the area forming a flat event horison that spirals down to the singularity - my question is this why is the event horizon is spiral/flat, surely a object so dense would create a spherical vortex that attracts visible matter from all directions

    If not a spherical then irregular because there would be different amounts of matter in different directions around the singularity?


Comments

  • Registered Users, Registered Users 2 Posts: 776 ✭✭✭Tomk1


    As I can recall it's just the term used for the point between light escaping and not escaping therefore called an Horizon. I think Hollywood does what they allways does under artistic licence


  • Registered Users, Registered Users 2 Posts: 1,683 ✭✭✭monty_python


    what happens when something goes into a black hole????
    does it not excist anymore???


  • Closed Accounts Posts: 2,980 ✭✭✭Kevster


    User45701, I don't understand exactly what your question is. However, a black hole does indeed just draw in matter from all directions but, because it is itself rotating (and at a different speed than the matter it draws-in), the matter is drawn-in in a spiral direction. I hope this explains it. I'm not sure if I'm absolutely correct here though.

    monty_python, when matter is drawn-into a black hole, it just turns to energy, like the type of energy that was in existence at the beginning of the Universe (i.e. - no protons, electrons, etc; just pure energy).


  • Registered Users, Registered Users 2 Posts: 1,683 ✭✭✭monty_python


    Kevster wrote: »
    monty_python, when matter is drawn-into a black hole, it just turns to energy, like the type of energy that was in existence at the beginning of the Universe (i.e. - no protons, electrons, etc; just pure energy).
    so basically it is nothing?? thats hard to get the head around


  • Closed Accounts Posts: 2,980 ✭✭✭Kevster


    hehe, no no, it most definately IS something. Pure energy is a 'something'. Think of it like this: At very high temperatures, no atoms will be able to form because the fundamental particles (such as quarks) are moving around at such high speeds that they cannot agglomerate together (i.e. - they have far too much energy). However, as the temperature decreases, the particle are able to agglomerate and they begin to form protons, neutrons, & electrons. As you decreases the temperature further still, these then 'agglomerate' to form atoms.

    So, the energy in a black hole is so high that the sub-atomic particles just cannot agglomerate and are thus referred to as pure energy.

    Be warned that I'm only an amateur astrophysicist!

    Kevin.


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  • Registered Users, Registered Users 2 Posts: 71 ✭✭Donegal_TDI


    This question is a good one, and something I have never got a successful answer to over the years. One would think that a black hole would attract matter from all directions, which it does, however animations showing the event horizon show a 2d ring of gas/matter around the throat with perhaps a burst of energy coming from top and bottom poles of the entity, which is generally considered to be a quasar if viewed straight on.
    I suspect everything attracted ends up in this ring, no matter what direction it came from, before ingestion.


  • Registered Users, Registered Users 2 Posts: 6,905 ✭✭✭User45701


    Kevster wrote: »
    User45701, I don't understand exactly what your question is. However, a black hole does indeed just draw in matter from all directions but, because it is itself rotating (and at a different speed than the matter it draws-in), the matter is drawn-in in a spiral direction. I hope this explains it. I'm not sure if I'm absolutely correct here though.

    I was more trying to understand .... what im trying to say is since the amount of matter in the different directions around the black hole would be different would there not be multiple (kind of spiral whirlpool type vortex's) approaching the event horizon from multiple directions because as you pointed out the blackhole itself is spinning which creates a visable flat disc(atleast in all documentry's and scifi's ive seen)

    I dont understand why in space why the disc is flat


  • Closed Accounts Posts: 65 ✭✭Svenolsen


    Nice animation here.(You have to keep clicking the arrow buttons to go forward.)

    http://www.thinktechnologies.com/portfolio/demos/Blackhole.html

    .


  • Registered Users, Registered Users 2 Posts: 71 ✭✭Donegal_TDI


    Excellent link, thank you.
    Helps a lot to be able to visualise a concept.


  • Closed Accounts Posts: 911 ✭✭✭994


    what happens when something goes into a black hole????
    does it not excist anymore???
    Its structure would be destroyed, but the matter/energy still exists.


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  • Closed Accounts Posts: 1,084 ✭✭✭A7X


    User45701 wrote: »
    I was more trying to understand .... what im trying to say is since the amount of matter in the different directions around the black hole would be different would there not be multiple (kind of spiral whirlpool type vortex's) approaching the event horizon from multiple directions because as you pointed out the blackhole itself is spinning which creates a visable flat disc(atleast in all documentry's and scifi's ive seen)

    I dont understand why in space why the disc is flat

    Try and picture it in your head. The black hole is rotating faster than the matter it is sucking in. Therefore the matter, which is under its pull, is being sucked in and around in a circle because the force which is sucking it in is circling also.

    If the black hole was still and still sucking things in there would be no disc surrounding it, just matter going in on a direct line from where it was to the hole.

    I hope that can help you picture it. Thats the way I do.


  • Closed Accounts Posts: 31 T3h-Slayer


    basically, around the black hole, there is usually an accretion disc where matter rotates slowly and is slowly drawn towards the center of the disc, and as it moves closer, it gradually spiral faster and faster and at some point, the particles emits radiation in the X-ray spectrum. also, black holes tends to ejects matter in the form of gas jets. the event horizon is the point beyond which nothing can escape the black hole., in other words, you can calls it the boundary of the black hole or something like it.


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