B What Happens When Light Approaches a Black Hole?

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what happens to light as it approaches a black whole
Hello I am not a physics student and i don't know anything about science, but i was curious if someone could tell me about what happens when light approaches a black hole i have heard that nothing goes faster than light but i have also heard that black holes can suck in light, combined with the fact that if a person was to enter a black whole whatever was clossest would move towards the center faster than whatever was far away does this not affect light the same way because it can't move faster than it already is? so does the light just turn and head towards the black hole at the same speed with no loss of speed and no increase in speed? and does this mean that light has mass? because how can it affect something with no mass?
 
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Defining speed in relativity is a somewhat tricky thing. Local measurements will always have light going at the same speed and everything else going slower. Remote measurements can give almost anything as a speed - it depends how you choose to define "space" and "time" in spacetime. The key fact is that, however you define speed, nothing ever overtakes a light pulse in vacuum under any circumstances.

Light does not have mass. Relativity models gravity as the curvature of spacetime - everything is affected, with mass or without. Light paths are curved towards the black hole, just like everything else (or at least the path through space is curved - the path through spacetime is straight).
 
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Likes vanhees71 and Nugatory
very cool thanks for explaining it to me
 
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