How does space-time curvature affect light?

AI Thread Summary
Space-time curvature around massive objects, like black holes, significantly affects the path of light. While light travels in straight lines, the curvature of space can bend these paths, causing light to follow a curved trajectory. Near a black hole, the gravitational pull is so strong that at the event horizon, all possible paths for light lead inward, preventing escape. This differs from the bending of light observed around less massive objects, such as the Sun, where light can still emerge after being deflected. Ultimately, the extreme warping of space-time near black holes creates conditions where light cannot escape, illustrating the profound effects of gravity on light behavior.
lynchmob72
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If space is warped around heavy objects in space, i feel that space would be FUBAR around black holes. So, my question is, Does light get sucked in by gravity, or does it just get caught in the warped space around a black hole?
 
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lynchmob72 said:
If space is warped around heavy objects in space, i feel that space would be FUBAR around black holes. So, my question is, Does light get sucked in by gravity, or does it just get caught in the warped space around a black hole?
Gravity IS the "warped spacetime".
 
phinds said:
Gravity IS the "warped spacetime".
Well, I understand that gravity is space pushing on you (Thanks to Relativity). My problem is, Light travels in a straight line. Warped space will bend light, but not make it disappear. I know that a black hole funnels space to the center or singularity, but i also know that warped space can't hold light. When the solar eclipse that proved Relativity happened, light traveled through warped space, then came out of it so we could see it. It should have wrapped around the sun, but it didn't. So, i wonder.
 
lynchmob72 said:
It should have wrapped around the sun,
"around"? The path of the light and the mass / diameter of the Sun would only produce a slight warping effect, which is what was seen. These effects are all a matter of degree and mostly cannot be seen at all because the conditions are not extreme enough.
 
lynchmob72 said:
My problem is, Light travels in a straight line. Warped space will bend light, but not make it disappear. I know that a black hole funnels space to the center or singularity, but i also know that warped space can't hold light. When the solar eclipse that proved Relativity happened, light traveled through warped space, then came out of it so we could see it. It should have wrapped around the sun, but it didn't.

Yes, light travels in a "straight" line, and curvature can mean these straight lines aren't really straight (rather as a straight line on the curved surface of the Earth will bend as it follows that curved surface).

The sun is not a black hole; its gravitational field is just strong enough to bend the path off to one side a bit. That's what Eddington's group observed in the solar eclipse (and we have since seen many more spectacular examples - google for "gravitational lensing").

The spacetime curvature near a black hole is so strong that at the event horizon all the straight-line paths that light can follow ("light-like geodesics" or "null geodesics" in the lingo) lead inwards. At the event horizon light cannot escape because there is no path out; move at the speed of light in any direction and you'll still end up inside the black hole.
 
Thank you for the replies.
 
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