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Black Holes and Worm Holes

  1. May 14, 2009 #1
    Hey guys,
    This may be a silly question. I saw star trek the other day, and I know it is science fiction but I was wondering...My understanding is that black holes are a region in space-time from which nothing can escape. However it seems like in the movie they are also used to travel through space time but I thought only wormholes could do that. In general can black holes be used to travel through space time and how do black holes and worm holes differ?
  2. jcsd
  3. May 14, 2009 #2
    Some scientists think... A blackhole is a singularity of infinite density matter maybe from a collapsed star. They are classified in groups by mass from tiny to super massive. Yes you are correct the pull of gravity is infinitely strong and the singularity's mass is compressed so tight it has zero volume. This causes an effect called the event horizon from which not even light can escape. Its the light falling into the singularity that causes this effect. So the inside is invisible. Cool right? Nope its a death trap for all matter. LOL Nothing ever comes out. The real truth is we really just do not know atm what really is at the center of one. I know I will not be first to go and find out LOL.

    You could wiki Blackholes, Singularity and wormholes.
  4. May 14, 2009 #3
    There is no evidence to suggest that black holes could be used for travel. The tidal forces at work as you cross the event horizon of a BH are so enormous that you would be torn apart. Or atleast that's what I believe, there are people more knowledgeable in this forum than I. There is no evidence for the existence of wormholes.
  5. May 14, 2009 #4
    You are right about black holes (what they are). As for traveling through space using them, it would not be possible. The curvature is so immense that you may be able to, in a sense, orbit the black hole for a short period of time (or what you think is a short period of time), and come out of the orbit having traveled a larger distance than regular. But, if you are looking to jump across the heavens, this is not going to work. A black hole sucks you down, but it never spits you out. Nor does one ever open a gateway to another place in the universe. Wormholes do that.

    Wormholes are basically gateways to and from places in the universe. They consist of a black hole, and a white hole. Incase you don't know, a white hole is the opposite of a black hole. Instead of sucking in matter, it would spew you out. This peculiar concept arises from the hypothesis of negative mass matter. When the two holes meet in hyperspace, the singularites (one a negative singularity, one a positive), in a sense, 'fuse,' and a path through hyperspace is formed. Immense pockets of radiation would immediately burst out both ends of the wormhole, and the gateway would be unstable. This is all theoretical. We have never seen a wormhole. Neither have we ever observed exotic, negative mass matter.
  6. May 27, 2009 #5
    Black Holes are stars that have exploded and caused a rift in space-time. Black Holes have an immense amount of gravity where not even light can escape. Anything that passes close to the event horizon is quickly ripped apart by the gravity, so trying to travel through it will be impossible. Some people theorize that there are such things called "White Holes", these have never been seen before, so it is purely for trying to explain a way of saying where things that the Black Hole "suck" in, end up. White Holes are the opposite of Black Holes, they, as previously mentioned, exert matter. The hypothesis of White Holes have been connected to the thought of that, every Black Hole is connected to a White Hole, where what the Black Hole suck in is spat out from the White Hole.

    Wormholes are holes which lead from one point in space to another. Take a piece of paper, fold the two ends together and punch a hole through. This is essentially a wormhole. Kind of a "short-cut" from a place to another. Wormholes are in something that people call "hyper-space", you have probably heard of hyper-space travel in many sci-fi movies and series. These movies aren't that far off, from a figurative stand point. However trying to use this "hyper-space" for anything but hypothetical calculations, is way beyond us.

    I guess you can look at Black Holes as unstable wormholes, which we won't be able to use for anything. Wormholes are created by putting an immense preasure to a certain point in space.

    I'm not an expert on this, but all I have said here is what I have gathered from books and documentaries.
  7. May 27, 2009 #6
    Black holes come from solutions of the equations of general relativity, as developed by Schwarzschild many years ago. One feature of his space-time solution was the "wormhole" or Einstein-Rosen bridge, which seems to link two separate parts of space-time or even two separate space-times/Universes. When John Wheeler (who also invented the term "black-hole") restudied the Schwarzschild solution in the early 1960s he found that it pinched off as a singularity before anything could pass through it, even light. The work of Wheeler, and various others, showed that non-rotating stars of sufficient mass could collapse into singularities, thus (briefly) forming an Einstein-Rosen bridge.

    When solutions of Einstein's equations for charged (Reiner-Nordstrom solutions) and rotating massive stars were studied further in the 1960s "wormholes" also appeared. The rotating collapsed star ("collapsar") solution of Kerr & Newmann produced a ring-shaped singularity, which at the centre of which was a large "wormhole" that didn't immediately shut-off quicker than light could travel. In the 1970s this was the main wormhole in science-fiction, notably Joe Haldeman's "The Forever War" and stories like George Zebrowski's "Fountain of Force". However by 1980 the fate of small infalling masses was studied and it was discovered that the gravitational distortions caused by such falling masses would cause the wormhole to shut-up before it could be traversed.

    Carl Sagan was writing an SF novel in the mid 1980s ("Contact") and wanted a physically possible wormhole, so he asked his good friend, physicist Kip Thorne, how that might be done. Thorne, and his graduate students, developed solutions for stabilising wormholes against self-collapse and collapse by infalling masses. This eventually led to the modern study of wormholes and how to keep them open using "exotic matter" or "negative energy" and similar hard-to-make stuff.

    But can the wormhole inside a black-hole be used? Igor Novikov, and colleagues, haven't given up on the wormhole inside and have written several papers that hint it might be traversed if the black-hole is big enough and old enough. Tidal forces can be extreme near black-holes that are too small, but above about 30,000 solar masses a black-hole might be traversible.

    As for "whiteholes" they are time-reversed black-hole solutions. To avoid recollapsing into their own event horizons a white-hole must expand forever and it also must exist since the beginning of the Universe... if that sounds like the Big Bang, then you've noticed a similarity that lots of people have also noticed. The two aren't exactly the same, but some theorists - like Lee Smolin - have proposed that the collapsing matter of a black-hole actually forms a new universe that branches off from our own. One day such theories might produce observable results, but for now they're speculative - interesting, but not yet empirically supported. Like wormholes.
    Last edited: May 27, 2009
  8. Sep 6, 2009 #7
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