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Homework Help: Need quotes on Black Holes

  1. Dec 10, 2004 #1
    hey guys, i have a research paper to turn in tomorrow, at my school. in each paragraph i need a quotation from someone supporting my answer, but i absolutely could not find any! could you all help me? (technically the quote just has to support the general idea found in each paragraph)

    here's what i've wrote so far:

    Black Abyss​

    A black hole is an extremely dense celestial body, which has been theorized to exist in the Universe. Black holes black holes are the result of giant starts dying, and collapsing on itself to a singularity having infinite density and infinite temperature. Both time and space stop in black holes, and anything that goes inside the event horizon of a black hole forever disappears from the visual Universe. Since not even light can escape the gravitational force of a black hole, it can’t shine or reflect any kind of signal, making it practically invisible and very hard to detect. Understanding the nature of black holes, as how they form, what they’re like, and how humans know they exist can lead to a better understanding of how the Universe works.

    The way a black hole forms is ironically from the brightest event in the Universe, a supernova. Supernovae is the name scientists use to refer to the explosions of stars. A supernovae explosion can shine with the brightness of a billion suns. A star dies when it has used up all of its fuel, which leaves it with no heat to counteract the force of gravity. Whatever material is left over collapses in on itself. The mass of the star before it died determines what it will become. Stars that are about the same size as the sun become white dwarfs, which glow from left over heat. Stars that have three times as much mass as the sun collapse into neutron stars. And a star that has over three times the mass of the sun gets crushed into a single point, which is called a black hole.

    Once the giant star has died and the black hole formed, all its mass is squeezed into a single point. The point at the center of black holes is called a singularity. Within a certain distance of the singularity the gravity is so strong that nothing, not even light can escape it. Event horizon is the name of that distance. The event horizon is not a physical boundary, but rather a gravitational one; it is the point of no return for anything that crosses it. When people talk about black holes, they are referring to the size of its event horizon. A black hole has 0 volume, therefore infinite density, which means a black hole never gets bigger, only its event horizon. The greater the mass the singularity has, the bigger the event horizon will be. The gravitational force of the black hole is the same as when it was a star, because gravity depends on how much mass there is. So the black hole has the same mass as the star, only compressed. Many people think that the intense gravity of black holes can not be escaped. But it is not so to that extent, planets and stars at a safe distance orbit around the black hole, much like how our solar system works.

    fyi, the quote would be placed in the last sentence of every paragraph
  2. jcsd
  3. Dec 10, 2004 #2
    bump bum bump
  4. Dec 10, 2004 #3


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    Why not just google "black hole", replace one of your statement by an equivalent one from an ariticle and add, "says <whoever wrote the article>" at the end.
  5. Dec 10, 2004 #4
    "...i absolutely could not find any..."

    I guess he tried that :grumpy:

    what does 'bump bump bump' mean?
  6. Dec 10, 2004 #5


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    Go to a local university library and skim through a couple of books on general relativity. Two I can recommend off the top of my head are "A Short Course on General Relativity" by Nightingale, and "Gravitation" by Misner, Thorne, and Wheeler. The Nightingale book is short and much quicker to navigate; it has one chapter on black holes, and all the quotes you could possibly need will be right there.

    - Warren
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