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Lv 6

Are black holes really black?

Update:

It seems to me that, if a black hole swallows all light that reaches it, while bending all of the other nearby light, that we wouldn't see a black hole. It seems to me that we would see the stars behind it distorted into some sort of mirror-like convex image. Am I way off base or am I on to something?

13 Answers

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  • 6 years ago

    Black holes are not really black but in fact glow with a certain kind of black body radiation known as the Hawking Radiation that is predicted to be released by black holes near the horizon(the edge of a black hole or popularly known as the Point of No Return) due to quantum mechanical effects.To spot a black hole is quite easy.It will appear as a location in the space (completely dark) with stars hurtling towards it.The complete opposite of a torch light in a completely dark room.

  • ?
    Lv 7
    6 years ago

    Anything that emits no light is by nature black, and black holes neither emit nor reflect light. The term "hole" is a bit metaphorical, however. They are a region of space-time that is cut off from the rest of the universe. In terms of gravitational space-time curvature, any object with mass can be described as a "hole". Black holes are just ones that cannot be escaped from by any physical means, including light.

  • ?
    Lv 4
    6 years ago

    A black hole appears black because not even light can escape the gravity of the hole. So it looks black, as there is no light coming off of it..

  • Ranger
    Lv 7
    6 years ago

    No they are not black, and they are not holes. They are round like a ball and have gravity so strong they pull everything to them and compress it so tightly that everything breaks down into the basic matter of the universe and is then sprayed out of the north pole and south pole of the black hole. They look like a top spinning around with lots of stuff circling it and moving closer with each orbit.

    Google them for pictures taken of the radiation created by breaking the matter down, they are actually rather beautiful to look at.

    Attachment image
  • 6 years ago

    There is no proof of black holes. But I would venture to guess if something called a "black hole" were to be proven to exist in our universe , it probably would be black , and appear to have a hole or mouth or gap . Thus ' black hole'

  • Anonymous
    6 years ago

    You might have seen some headlines over the weekend saying things like "Stephen Hawking declares: 'There are no black holes,'" or "Stephen Hawking says black holes don't exist." (Via ​CNET, Yahoo)

    Stephen Hawking is, of course, the Cambridge physicist most popularly associated with black holes for the last 40 years. (Via TED)

    Hawking gained fame in 1974 after coming up with the idea for something called "Hawking radiation," a way that black holes might shed some of their mass and evaporate over time.

    Black Hole photo

    (Getty)

    But unlike when Hawking published that theory, we actually have a long list of known black holes. So why is he now saying they don't exist? (Via NASA)

    In his new paper called "Information Preservation and Weather Forecasting for Black Holes," Hawking isn't arguing that what we know as black holes don't exist. Instead, he's arguing that they aren't truly black. (Via arXiv)

    Hawking's paper is weighing in on a debate that's been raging among theoretical physicists for the last year and a half. It's called the firewall paradox.

    It has to do with the edge of the black hole, the line known as the event horizon. And more importantly, what happens when you fall in. (Via NASA)

    Traditionally, physicists believed you would get squeezed and stretched like a piece of spaghetti.

    "The fabric of space and time funnels you down to this point. So in fact you're being extruded through the fabric of space like toothpaste through a tube." (Via Comedy Central / "The Daily Show")

    But back in 2012, some physicists began arguing that you would actually be flash-fried by high-energy particles, and that the event horizon is more like a "firewall," kicking off what The New York Times called "a high-octane debate" in the world of physics.

    The issue here is that both sides — the classical side and the firewall side — appear to be right according to different general theories of physics, and reconciling the two requires at least one major facet of physics to be wrong. The new paper is Hawking's attempt to sidestep that paradox.

    A writer for Discovery summarizes his argument: "Hawking thinks that the idea behind the event horizon needs to be reworked. Rather than the event horizon being a definite line beyond which even light cannot escape, Hawking invokes an 'apparent horizon' that changes shape according to quantum fluctuations inside the black hole — it's almost like a 'grey area.'"

    Getting rid of the event horizon — the thing that makes a black hole a black hole instead of a grey one — seems pretty extreme. Naturally, there's some resistance to the idea from physicists.

    One tells Nature: "​The idea that there are no points from which you cannot escape a black hole is in some ways an even more radical and problematic suggestion than the existence of firewalls."

    Another tells New Scientist: "​It is not clear what he expects the infalling observer to see ... It almost sounds like he is replacing the firewall with a chaos-wall, which could be the same thing."

    Back in 2012, Hawking referred to the idea that information can't escape black holes as his "biggest blunder." If his new theory is right, things that fall into the black hole aren't necessarily destroyed — though they would be scrambled beyond all recognition.

  • ?
    Lv 7
    6 years ago

    They are absolutely black , Energy cannot escape or reflect off them . Hawkings radiation can escape from them but you would only notice it if the black hole was really tiny.

  • 6 years ago

    the escape velocity of an object in a black hole is greater than the speed of light, so light can't escape. since they don't emit or reflect light, they're not really a color, so i guess you could say they're black.

  • 5 years ago

    Yes

  • 6 years ago

    they are invisible they may be black, they are called black since light doesnt get to it

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