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Black holes in a black hole?

  1. Oct 26, 2003 #1

    jimmy p

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    Black holes in a black hole??

    Hello, i have read in the NEW SCIENTIST magazine the other day about black holes. For anyone that hasnt read it, what it said was

    "In the depths of space, a star is born. Within a cold, dark cloud drifting aimlessly along the space lanes, a shrinking clump of gas lights up to become a fully fledged star. Like billions of stars before it, it was born in a rarefied and chilly part of the universe. Ir can look forward to a long life and a dignified death.

    But for some stars, life will not begin or end so peacefully. Over the past three years, astronomers have realised some unfortunate stars are born on the edge of a maelstrom of blisteringly hot gas swirling into a black hole. As these stars race through their lives they explode, leaving behind smaller black holes. These spiral inexorably down to their death in the bigger black hole. From the instant they are conceived, they are destined to be swallowed hole - baby black holes eaten by their own mother."

    Now what i wanted to know is how that would happen? and what would happen to the 'baby' black hole? lol...yucky thoughts..

  2. jcsd
  3. Oct 26, 2003 #2


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    The two black holes simply merge into one larger black hole, with the combined mass of both original black holes. There can be no such thing as a black hole within a black hole.

    - Warren
  4. Oct 26, 2003 #3
    I thought he was refering to black holes forming in the accretion disks of another black hole. 'Black hole within black hole' is a little misleading, I think he was including the accretion disk as being part of a black hole.
  5. Oct 28, 2003 #4
    Re: Black holes in a black hole??

    What happens for a unobserved mass of say the Sun (about 3km ) the area of Mass detaches outwards from the high density region. This Mass is constrained by the Unobserved Gravitational Dense region, so what actually happens is that a 3km invisible Star, gets inflated to a Star of about the Mass and size of our visible Sun.

    You can get a better idea if you get hold of a childs 'bubble-blowing' toy, or better still a drinking straw and some soapy water!

    Put some soapy water into your mouth, then placing the Straw to your lips, blow-out the soap gently..what emerges is a neat bubble, if you are really good you can the bubble just enough air for it to float away!

    In the Galactic core, this is what happens, but Blackholes give birth to Whiteholes..or Stars to you and me.
  6. Oct 28, 2003 #5
  7. Oct 28, 2003 #6


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    Whatever you do, don't listen to ranyart.

    - Warren
  8. Oct 28, 2003 #7
    It would seem inconcievable that somebody would attempt such a thing, but if YOU? was just about to try it (and pulled back at just the right moment) then you have every right to warn others.

    Tell me..at what moment did you realize imminent danger? and did you consider another alternative, such as just a standerd everyday experiment like at school and blowing into a saucer containing a little harmless quantity of washing-up liquid would do the trick just the same, ..careful though not to blow to hard..you may ignite the H2O contained within a bubble..or at the very least set of a chain-reaction of Sonoluminecant Catostrophic Cherenkov Gamma Burst!

    Talk about PANIC!! ..I nearly did?

    P.S I take full responsibility if one or two soap-bubbles actually burst.
  9. Oct 28, 2003 #8
    CHroot, you are right, there may be one or two 5 0r 6 year olds lurking around delving into String theory or..dare I say it Inflationary models, so do not..I REPEAT DO NOT TRY THE ABOVE.
  10. Oct 28, 2003 #9
    Re: Black holes in a black hole??

    One can use a Inflatory model I believe Linde had a paper or two on it. If one uses a simplistic view;http://uk.arxiv.org/PS_cache/astro-ph/pdf/0310/0310517.pdf

    and proceed to imaging a 'lemonade soda' bottle, as you turn the top open, a flux of bubbles emerge from the clear soda. Now imagine a soda bottle with two symmetric necks, and two caps, imagine you were on a spaceship..close to the Galactic plane, at the Galactic core, you take the bottle outside the ship..turn both caps similainously, letting go at a precise instant.

    Now what you have is representative of Galactic 'outflow', from within the core, each bubble pours out and seperates..this is inflation, from a Galaxy emergent viewpoint.

    Blackholes blow out Stars.
  11. Oct 28, 2003 #10


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    Actually, chroot is right here: Ranyart is dead wrong.

    Let's just tick them off, right?

    Black holes aren't bubbles.
    White holes aren't stars.
    Masses aren't measured in km.
    Unobserved Gravitational Dense region seem to have been just made up for fun.
  12. Oct 28, 2003 #11
    Minor correction: in GR, masses are often measured in kilometers; convert mass in kilograms to mass in meters by multiplying by G/c2. The Sun thus has a mass of of about 1.5 kilometers (Schwarzschild radius of about 3 kilometers, since RS = 2GM/c^2).

    The rest of raynart's first post doesn't make sense, though.
  13. Oct 28, 2003 #12


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    Unfortunately, he was talking about a "piece" of the Sun 3 km in radius.

    - Warren
  14. Oct 28, 2003 #13
    ME! I was itching to write (3km in comparative size for mass) and theorized Blackhole instead of (Unobserved Gravitational Dense region ):wink:

    I do contend that Linde's model streches back to an Universal Singularity the Big-Bang/Inflation .

    But Relativity states Singularities exist to where our Galaxy dissapears, if one make a true linear reverse-time calculation, as our Galaxy dissapears into the Space whence it came.

    It is not that Time started at the big-bang, it is that percieved Time, the dependant Time and Space came together fused to our Galaxy,from the intervening Space..which is Non-Time-dependant.
  15. Oct 28, 2003 #14
    No, I think unobserved gravitationally dense invisible star whatnots are just his weird way of talking about black holes and Schwarzschild radii ... but he can speak for himself.
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