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Some questions about galaxys

  1. Jun 21, 2003 #1
    [SOLVED] Some questions about galaxys

    Hi guys this is my first message

    Can we assume that every spiral galaxy has a massive black hole at the center?

    And why dont elliptical galaxys evolve like the spirals?

    Has anyone wondered were all the energy goes that gets sucked in to a black hole?
  2. jcsd
  3. Jun 21, 2003 #2


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    Hopefully several other people will reply----several parts of question.

    About ellipticals, the last explanation I heard is that ellipticals are formed by the collision and merger of two or more other galaxies (which may e.g. have originally been spirals)
    and an elliptical can have more than one massive black hole
    in its central region.
  4. Jun 21, 2003 #3
    It's the more probable.There's a theory that says that all the AGN (Seyfert galaxies, quasars, BL Lac objects,...) are only galaxies where the central black hole is eating big quantities of material, and then shine so brightly because that material is accelerating and
    giving radiation
    All depends how the cloud that gives rise to the galaxy rotates. If the cloud rotates rapidly, becomes a spiral galaxy, and if rotates slowly, an elliptic galaxy
    I think that remains inside the black hole. Others would say that travels through a wormhole and go out from a white hole, but it's more sci-fi than pure science
  5. Jun 28, 2003 #4
  6. Jun 28, 2003 #5

    well for me black holes come pretty close to sci-fi and i know everything we dont understand is scifi or not possible, maybe an idea is that this is the krib of a new universe, it s a lot of energy thats been sucked in

    im not educated on a high lvl in this but i like to think about it, thanx for the replies:smile:
  7. Jun 29, 2003 #6
    No, not mass,I'm speaking about velocity of rotation. All the non-compact bodies that spin tend to have a flatlike form (for example, the sun that spin over itself, has more diameter in the equator than from pole to pole)Greater the velocity of spin, greater the flatlike form
    Black Holes exists in the middle of elliptic galaxies too.The famous galaxy M87, that lies inside the Virgo Cluster, is elliptic, and has a BH of Solar masses. It's the more massive black hole known.In comparation, Sagittarius A, the Black Hole of the center of the Milky Way, has a mass of only 3 million solar masses
    Interesting idea! Lee Smolin, in his book The life of the Cosmos has proposed the idea of the evolutionary universe. He says that every time that a black hole is created, gives rise to a new Universe. Then if you fall inside that black hole, you will go to that universe, that can has black holes that if collapses creates another universe..., and so on.
    Last edited: Jun 29, 2003
  8. Jun 29, 2003 #7
    Energy is mass. There's no real difference between them, so there's no problem as regards energy and black holes.
  9. Jun 29, 2003 #8
    I am sure i watched a programme on BBC a couple of years back that said that they think that most Galaxies do have a Black hole at the centre and that includes are own galaxy, not 100% sure about this though, certainly aint no expert.
  10. Jun 29, 2003 #9
    Yeah, that's right (to my knowledge). Many galaxies, including our own, have a massive black hole at the centre (and possibly smaller black holes, too).
  11. Jun 30, 2003 #10


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    That seems to the be the trend in the new data. It's still a relatively new discovery though so there is still a lot more research to be done.

    Galaxy formation is also an area of much research.
    I've only skimmed the intro, but this seems to be an interesting scientific (very technical) paper on the subject...

    Yep, many people have. :wink: My hunch is that it stays there.
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