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Space-Time Loops May Explain Black Holes

Discussion in 'Science & Technology' started by micropage7, Jul 11, 2013.

  1. micropage7

    micropage7

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    [​IMG]
    Black holes can't fully be described by general relativity, but physicists hope to understand the inner workings of these strange objects by applying a theory called loop quantum gravity.


    Physics cannot describe what happens inside a black hole. There, current theories break down, and general relativity collides with quantum mechanics, creating what's called a singularity, or a point at whichthe equations spit out infinities.

    But some advanced physics theories are trying to bridge the gap between general relativity and quantum mechanics, tounderstand what's truly going on inside the densest objects in the universe. Recently, scientists applied a theory called loop quantum gravity to the case of black holes, and found that inside these objects, space and time may be extremely curved, but that gravity there is not infinite, as general relativity predicts.

    This was the first time scientists have applied the full loop quantum gravity theory to black holes, and the results were encouraging, researchers said.

    "What they have done is a major step, because they have been able to provide a much more complete description of what really happens near the black hole singularity using loop quantum gravity," said Abhay Ashtekar, a physicist who studies loop quantum gravity at Pennsylvania State University, who was not involved in the new research."We still don't have a clear picture of the details of what happens. So it is opening a new door that other people will follow."

    A black hole is created when a huge star runs out of fuel for nuclear fusion and collapses under its own gravity. The star's outer layers are expelled, and its core falls in on itself, with the pull of gravity becoming ever stronger, until what's left is the core's mass condensed into an extremely small area. According to general relativity, this area is a single point of space-time, and the density there is infinitely large — a singularity.

    But most scientists think singularities don't really exist, that they're just a sign that equations have broken down and fail to adequately describe reality. Loop quantum gravity appears to be an improvement on general relativity in describing black holes because it doesn't produce a singularity.

    The idea is based on the notion of "quantization," which breaks an entity up into discrete pieces.Whilequantum mechanics says atoms exist in quantized, discrete states, loop quantum gravity posits that space-time itself is made of quantized, discrete bits, in the form of tiny, one-dimensional loops.

    "The loop means the fundamental excitations of space-time themselves are one-dimensional in nature," said Jorge Pullin, a physicist at Louisiana State University, who co-authored the new study with Rodolfo Gambini of the University of the Republic in Montevideo, Uruguay. "The fundamental building block is a loop, or network of loops. For a visual image, think of a mesh fabric."


    http://www.space.com/21903-black-holes-explained-space-time-loops.html
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  2. scoutingwraith

    scoutingwraith

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    Hmm.. I know this may sound weird but if matter or anything is quantized in the singularity of the black hole where does it go afterwards. This may sound weird but my personal opinion is that it maybe thrown by a white hole on the other side. Though thats highly unlikely.
  3. FordGT90Concept

    FordGT90Concept "I go fast!1!11!1!"

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    I'm still waiting for less theorizing and more probing (assuming "black holes" even exist).
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  4. W1zzard

    W1zzard Administrator Staff Member

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    there is plenty experimental evidence for black holes

    what scientists doubt is that black holes are "infinitely" small as predicted by current theories. very small, yes, but not infinitely. unfortunately we don't have any theories for quantum gravity, so we can't speculate about mechanisms that would counteract the force of gravity of all the stuff in the bh, to avoid "infinitely small".
  5. the54thvoid

    the54thvoid

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    The notion of a black hole is entirely real. It is realised as a super massively dense object of an exceptionally small size with an exceptionally powerful gravitational pull such that it has an event horizon from which nothing can escape.

    Our galaxy has one at it's core. This is evidenced by studies from radio wave telescopes that have pictured stars in orbits too tight and rapid to be dictated by any other source other than the theorised gravitational power of a black hole.

    The only issue from a physics standpoint is that we have no working knowledge or sound theory that describes the science 'inside' a black hole. Nothing, not even the OP is relevant from a 'factual' standpoint as unlike things like evolution and quantum physics, we have no observable or mathematically modelled and predicted theories that can be demonstrated.

    I would argue we can have no proper scientific theory of the internal workings of a black hole until we hold a much greater observable history of one. The giant gas cloud currently heading straight for Sagittarius A (our galactic core) may well start us off with some good info.
  6. magibeg

    magibeg

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    I've heard many theories about what *could* go on in a black hole but my favorite came from a friend of mine's professor in University. It's not too dissimilar to what is being suggested in this article.

    Basically it involves using Planck length. http://en.wikipedia.org/wiki/Planck_length

    Because of the density involved (although not infinite) it has compressed matter into a point the size of Planck's length. This puts a minimum size on how small a black hole can be as well as a maximum density (all the matter in the galaxy at Planck length size).

    Naturally past the event horizon Space-Time completely loops in on itself as well which gives you the black hole appearance. There is insane amounts of math that goes along with everything of course and Planck length hasn't been verified but it makes for a good thought experiment.
  7. W1zzard

    W1zzard Administrator Staff Member

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    don't need infinite density/gravity for infinitely small. you need a force that counteracts the force of gravity so equilibrium is reached at a certain size. no such force is known.

    https://en.wikipedia.org/wiki/Degenerate_matter
  8. theoneandonlymrk

    theoneandonlymrk

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    Counteracting force hmm ,no mention of dark matter or energy and how it reacts with a Bh ima say its that then.
    Have I just come up with a theory?.XD
  9. Flibolito

    Flibolito

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    Matter that enters a black hole eventually evaporates into radiation and leaves the black hole. Due to the nature of space time and the constant energy exchange of space time created pairs are split up at the edge of the event horizon. I takes a long time for a normal size black hole to evaporate but particle accelerators are going to be testing super tiny black holes evaporating instantly to study this further. Hence why the LHC is not a doomsday device. We just don't know what state matter is in once its inside the black hole. This is also one way looking into whats called a missing energy search to see if other dimensions with possible linked white hole are viable.
  10. FordGT90Concept

    FordGT90Concept "I go fast!1!11!1!"

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    Like? Einstein's theory of General Relativity had a provable test (measuring diffraction during a total solar eclipse). What is the provable test behind black holes? The closest black hole is likely Sagittarius A* and, well, none of our EMS equipment can read much anything about it. We can only guesstimate its size.
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  11. theoneandonlymrk

    theoneandonlymrk

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    Perhaps you have a better idea as to why various suns possibly but not likely with planetary systems, are wizzing round and round the centre then or the whole galaxy for that matter which Is spinning around something maybe its an ice cream van and we're all in the
    Que or maybe it is" Q "doing it.
  12. the54thvoid

    the54thvoid

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    This.

    [​IMG]

    It is the orbits of the stars at the centre of our universe. It is accepted to be the gravitational effect of a black hole on the stars that cause such orbits. Cosmologists agree on this.

    http://iopscience.iop.org/0004-637X/628/1/246/fulltext/62163.text.html
  13. FordGT90Concept

    FordGT90Concept "I go fast!1!11!1!"

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    It's something massive, no doubt, but that doesn't prove it is the theorized black hole (something even light can't escape).
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  14. the54thvoid

    the54thvoid

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    No. It's something massively dense. It is NOT massive - that's the point.

    EDIT:

    Read all of this please.

    http://www.astro.ucla.edu/~ghezgroup/gc/journey/smbh.html
  15. FordGT90Concept

    FordGT90Concept "I go fast!1!11!1!"

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    Indeed, it is only about the size of Earth but denser than many stars combined. Still doesn't prove light can't escape it. It's all theory and conjecture. Voyager satellites may tell us more about "black matter" than Sagittarius A* could.
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  16. the54thvoid

    the54thvoid

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    Read my edit
  17. theoneandonlymrk

    theoneandonlymrk

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    Wt , thats why there called black holes.

    And its OBSERVED fact.

    So to recap there is something there that Is spinning a galaxy with its energy and we cannot directly see it so its safe to say the Bh theory is on the right track, please don't tell me you're a creationist.
  18. FordGT90Concept

    FordGT90Concept "I go fast!1!11!1!"

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    Black holes alone can't explain a lot of the shapes galaxies take on nor can they explain why the universe is accelerating in growth. Dark matter certainly could, but that dark matter would have to be in the space between galaxies and not at the galactic centers. This is why I remain a skeptic until something (be it Voyager or a future vessel) definitively proves what dark matter is and where it is located. I'm not convinced Sagittarius A* has the answers we need.
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  19. theoneandonlymrk

    theoneandonlymrk

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    Your right in this but the fact that we don't know everything isn't necessarily indicative of anything , and certainly doesn't mean bh's don't exist but I agree there is a crazy amount to figure out yet, I mean I do not understand quantum theory at all but I do get some of what its trying to say and Dwave2's creators certainly get it yet it is still just a theory.
  20. PopcornMachine

    PopcornMachine

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    Very cool stuff.

    But I can't understand why people are questioning the existence of black holes. This about understanding them better, not questioning anything.

    There's tons of evidence for objects with mass beyond what we understand as sustainable in three dimensions.

    That said, I've always known we knew very little about what goes on inside one.

    This is the first time I've heard the term "singularity" described as a shorthand for something we can't explain.

    Although I have a hard time visualizing one-dimensional loops in space time, it sounds pretty cool. :D
  21. W1zzard

    W1zzard Administrator Staff Member

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    too weak

    it does, because it's too small and too massive to be a star

    to check if something is a black hole you can just plug in its size and mass into a relatively simple formula:
    r = 2 * G * m / c²
    if the right side is larger than the left side -> black hole

    you can also look at phenomena that emit a lot of energy (quasars), some change in luminosity. based on that interval you can estimate their size (one side of it can't know what the other side is doing, faster than the speed of light)
    Last edited: Jul 11, 2013
  22. FordGT90Concept

    FordGT90Concept "I go fast!1!11!1!"

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    You're assuming Schwarzschild was right.
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  23. W1zzard

    W1zzard Administrator Staff Member

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    Escape velocity has been sufficiently tested, otherwise NASA's rockets would be falling on your house.

    now just look for escape velocity > speed of light (_black_ hole). done

    even if the formula is wrong, there must still be objects which have escape velocity (no matter how high or calculated) higher than the speed of light (fixed).
    Last edited: Jul 11, 2013
  24. theoneandonlymrk

    theoneandonlymrk

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    Quasars proove energy can escape , after recently seeing the emense particle fields at the end of quasars it looks like the Bh if life lived and whole galaxy consumed would essentially create the remnant elements for a galaxy at each end(plumes seen perpendicular to the galxys spin from gamma ray bursts)given the time to re coalesce, we'll that's what I was thinking anyway
  25. Frick

    Frick Fishfaced Nincompoop

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    Protip: Don't bother with Ford.
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