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Power of a Black Hole's Mass

  1. Dec 6, 2011 #1
    Hey everyone!

    Research is one of my hobbies, and yesterday I decided to study both neutron stars and black holes. From my freshman year in High School in my Geology class, I remember being fascinated by astronomy, and what really caught my attention was the life of a supermassive star. I remember reading that the mass of a black hole is powerful enough to bend light. Is the mass of a black hole powerful enough to bend time and space?
  2. jcsd
  3. Dec 6, 2011 #2
    All mass bends time and space (one and the same, hence the expression spacetime), but black holes and neutron stars (and whole galaxy clusters) are the only objects who's mass is large enough to bend space on an obvious (visible) scale.
  4. Dec 7, 2011 #3


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    It is worth noting, since the OP specifically mentioned it, that a corollary to this is that ALL mass bends beams of light. This includes our own humble sun, and in fact was one of the first ways in which Einstein's General Relativity was confirmed: http://en.wikipedia.org/wiki/Tests_of_general_relativity#Deflection_of_light_by_the_Sun
  5. Dec 7, 2011 #4


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    The main difference (from the point of view fo gravity) between a black hole and other objects is that the gravity of a black hole is so strong that light can't escape.
  6. Dec 10, 2011 #5
    I would assume that BH bend space time much more than Neutron stars aswell for the significant increase in gravitation. Something like a black hole will suck in light is it gets close enough while something way less massive like the sun merely bends it slightly. Look up gravataional lensing to see a picture and better explanation of this.
  7. Dec 10, 2011 #6


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    Black holes only capture light that enters their event horizon. Photons that pass just outside the event horizon are gravitationally lensed.
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