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  1. 29 Aug '10 03:39
    Is it excepted as proven fact that they exist? How about that they are created by dying stars?
  2. Standard member sonhouse
    Fast and Curious
    29 Aug '10 05:01 / 2 edits
    Originally posted by USArmyParatrooper
    Is it excepted as proven fact that they exist? How about that they are created by dying stars?
    Black holes have a lot of evidence in favor of them but there is still debate as to their possibility. The evidence in favor is called Einstein rings. This shows that space itself can bend and bend the path light takes, the rings being light from a way distant galaxy say 10 billion light years away but exactly between it and us is another galaxy, say at 5 billion ly away.

    So being half way like that, the light from the distant galaxy is magnified, bent around the intervening galaxy and comes to us way distorted like a ring or an arc and astronomers can gain information about that distant galaxy that we couldn't have gotten if the intervening galaxy had not been there.

    That closer galaxy becomes like a giant telescope lens and it is the gravitational field of the entire galaxy as a whole that bends space enough for us to see that even further galaxy.

    What that means is if the mass of a collapsing star condenses enough, it more or less makes a hole in our space-time continuum and like a cockroach hotel, you can check in but you can't check out, not even light can escape, since the escape velocity would be greater than the speed of light so even photons are trapped.

    They have images that have been analyzed that suggests there is no other explanation for what they are seeing.

    The LHC in Cern is thought to be powerful enough to eventually create a tiny tiny black hole and one of the theories about black holes is the smaller they are the shorter they live before they uncollapse and make a reverse black hole, a white hole which spews out all the energy that was sucked in when it was made.

    So the ones at LHC if they succeed, would be so tiny they would blow up in microseconds or less and the particles that come out would be proof black holes exist, solid scientific proof. As of now they have observations that supports the black hole idea but of course we have none in the vicinity to send a probe to so it is still open to debate. All that debate would stop cease and desist if LHC actually makes one. It is proven the lesser bending of space actually exists because of Einstein, he predicted them and they were found. Dramatic photo's of rings. I'll try to find a link.

    Here is one, a black and white image from Hubble showing not one but a double ring!

    http://www.spacetelescope.org/news/heic0803/

    Here is a bit on black holes:

    http://hubblesite.org/explore_astronomy/black_holes/home.html
  3. 29 Aug '10 08:40
    As a general comment, nothing in empirical science is "proven fact".
  4. 29 Aug '10 10:17 / 2 edits
    Originally posted by KazetNagorra
    As a general comment, nothing in empirical science is "proven fact".
    Would you say that the existence of rainbows is NOT a “proven fact”?

    -we know they exist by empirical observation. I would say that, using every-day English, there existence is a “proven fact”.
  5. 29 Aug '10 11:05 / 1 edit
    I'd like to describe the truthness of Black Holes like this:

    We have observations of something out there. Strange behaviour of certain objects. Pictures, spectres, readings of radiations, and such.
    We also have theories of what happens when a star of certain sizes dies, how matter compresses, how extreme densities behave, and such.

    When observations and theories coincides, then we can interprete this that the theories are correct. Any discrepencies require more observations, and/or more theory refinements.

    If another theory is invented that could describe observations better than the current one, then we change theory. About Black Holes, no basic new theory is needed. But, still, in the fringes of the theory more observations are needed, and observations not explainable by the theory needs finer adjustements.

    We don't know everything about Black Holes. Yet. And we will never know the exact Truth about Balck Holes. I.e. the theory will never be completed. But we will reach the real Truth asymptotically.

    Same goes for BigBang, Evolution, Gravitation, and any other scientific theories.
  6. 29 Aug '10 11:15
    Originally posted by Andrew Hamilton
    Would you say that the existence of rainbows is NOT a “proven fact”?

    -we know they exist by empirical observation. I would say that, using every-day English, there existence is a “proven fact”.
    Yes, I would say that.
  7. 30 Aug '10 18:20
    Originally posted by sonhouse
    The evidence in favor is called Einstein rings.
    Though an interesting phenomena, I really don't see how this has anything to do with black holes. It is one of the many lines of evidence that light space is curved by gravity, and it helps us work out the mass and distribution of that mass in some galaxies, but what does it have to do with black holes?
  8. 30 Aug '10 18:23
    Originally posted by USArmyParatrooper
    Is it excepted as proven fact that they exist? How about that they are created by dying stars?
    Black holes can theoretically form when a massive star runs out of fuel and collapses.
    I believe they could also form if a star becomes massive enough, to create a black hole even without running out of fuel.
    The object at the center of our galaxy is so massive that it almost certainly has to be a black hole.
  9. 30 Aug '10 19:42
    Originally posted by USArmyParatrooper
    Is it excepted as proven fact that they exist? How about that they are created by dying stars?
    http://en.wikipedia.org/wiki/Black_hole#Observational_evidence

    ...

    Contents

    4 Observational evidence

    * 4.1 Accretion of matter
    * 4.2 X-ray binaries
    o 4.2.1 Quiescence and advection-dominated accretion flow
    o 4.2.2 Quasi-periodic oscillations
    * 4.3 Gamma ray bursts
    * 4.4 Galactic nuclei
    * 4.5 Gravitational lensing
    * 4.6 Alternatives

    ...

    Gravitational lensing

    The deformation of spacetime around a massive object causes light rays to be deflected much like light passing through an optic lens. This phenomenon is known as gravitational lensing. Observations have been made of weak gravitational lensing, in which photons are deflected by only a few arcseconds. However, it has never been directly observed for a black hole.[99] One possibility for observing gravitational lensing by a black hole would be to observe stars in orbit around the black hole. There are several candidates for such an observation in orbit around Sagittarius A*.[99]

    ...
  10. Subscriber AThousandYoung
    Do ya think?
    30 Aug '10 20:29
    Originally posted by sonhouse
    Black holes have a lot of evidence in favor of them but there is still debate as to their possibility. The evidence in favor is called Einstein rings. This shows that space itself can bend and bend the path light takes, the rings being light from a way distant galaxy say 10 billion light years away but exactly between it and us is another galaxy, say at 5 b ...[text shortened]... re is a bit on black holes:

    http://hubblesite.org/explore_astronomy/black_holes/home.html
    Wow. That was a clear and informative post.
  11. Subscriber AThousandYoung
    Do ya think?
    30 Aug '10 20:33
    Originally posted by Andrew Hamilton
    Would you say that the existence of rainbows is NOT a “proven fact”?

    -we know they exist by empirical observation. I would say that, using every-day English, there existence is a “proven fact”.
    What if the the secret masters of the world implanted all memories of rainbows, all rainbow images in books in everyone's mind? It COULD be true!
  12. Standard member forkedknight
    Defend the Universe
    30 Aug '10 23:03
    Originally posted by AThousandYoung
    What if the the secret masters of the world implanted all memories of rainbows, all rainbow images in books in everyone's mind? It COULD be true!
    A supernatural ninja-edit of sorts?
  13. Standard member sonhouse
    Fast and Curious
    30 Aug '10 23:50 / 1 edit
    Originally posted by twhitehead
    Though an interesting phenomena, I really don't see how this has anything to do with black holes. It is one of the many lines of evidence that light space is curved by gravity, and it helps us work out the mass and distribution of that mass in some galaxies, but what does it have to do with black holes?
    Einstein rings are proof that space-time is malleable. That's all. A big step in the realization that at the end of the road of such space-time bending is the ultimate one, black holes. That's why those rings are a big arrow pointing to at least the possibility that black holes can be real. What would constitute proof would be sending a probe to orbit one of them, the probe being in an orbit that allows the thing to survive and able to then conduct experiments like shoveling matter to spiral in and watching the proceedings, it would be that kind of thing that would settle the issue. Till then it's all theory, or conjecture.

    Alternately we would have to be able to manufacture artificial black holes, they would of course be very tiny and wouldn't last more than a few microseconds but the decay into matter would leave a clear signature a lot different from say, a proton-antiproton beam collision. The LHC may be powerful enough to do that. News at 11.
  14. Standard member sonhouse
    Fast and Curious
    30 Aug '10 23:58
    Originally posted by Andrew Hamilton
    Would you say that the existence of rainbows is NOT a “proven fact”?

    -we know they exist by empirical observation. I would say that, using every-day English, there existence is a “proven fact”.
    We have more than that, we can exactly recreate the conditions of a rainbow in the lab and indeed in our back yards, with just a water hose spraying into the air. I would think that would bring rainbows out of the theory stage and onto the proof stage.

    Has anyone ever brought forth an alternate theory that would even have a chance of falsifying the current ideas of rainbows? I don't think so. It seems pretty clear you take water drops in an atmosphere like Earths, or maybe even in space, make the droplets X size and Y volume, put light behind it and there will be a rainbow.

    What other way of looking at this phenomena would you suggest but that?

    Mass hypnosis? Optical hallucination?
  15. 31 Aug '10 06:13
    Originally posted by sonhouse
    Einstein rings are proof that space-time is malleable.
    They are proof that light bends due to gravity. I am not so sure that they prove that space bends too. Besides, we have many other sources of evidence that Einsteins theories are correct.