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Thunder Foot
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This is probably a dumb question, but if Einstein proposes that nothing can travel faster than light via Special Relativity, then what is the speed at which light gets sucked into a black hole?
Thunder Foot said:Once again, I apologize if its a stupid question... I'm just trying to understand Special Relativity. But wouldn't gravity have to be attracting light at a greater speed to change its direction? Say, light is traveling by a black hole, and gets pulled in. Would that mean that light is then traveling at the speed to which gravity attracts it towards the black hole?
Thunder Foot said:This is probably a dumb question, but if Einstein proposes that nothing can travel faster than light via Special Relativity, then what is the speed at which light gets sucked into a black hole?
That rule belongs to special relativity. In general relativity the speed of light may have different values. From an observer at rest outside the black hole he will reckon that a light beam falling radially in towards a black hole will eventually slows down, i.e. the speed approaches zero as the light proceeds toward the event horizon. The light never passes through the event horizon from the external observer's point of view, so it never gets "sucked into" the black hole. The frequency of light diminishes to such a low value that it eventually becomes invisible to any instrument of finite precision.Thunder Foot said:This is probably a dumb question, but if Einstein proposes that nothing can travel faster than light via Special Relativity, then what is the speed at which light gets sucked into a black hole?
pervect said:We've had this discussion before.
Using local clocks and rulers, the speed of light in a vacuum is always equal to 'c', even in GR.
However, the coordinate speed of light is not necessarily equal to 'c'.
One has to be very precise as to how the 'speed' is being measured.
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yogi said:Pervect - can you give some examples - e.g., do you consider the one way sagnac correction used in GPS to be an example of a non "c" coordinate light speed?
The speed of light is a fundamental constant of the universe and is approximately 299,792,458 meters per second. However, when it is sucked into a black hole, its speed can approach the speed of light, but it can never exceed it.
The speed of light remains constant near a black hole, but the gravitational pull of the black hole can cause light to appear to slow down or even stop. This is due to the bending of space-time by the immense gravity of the black hole.
The strong gravitational pull of a black hole makes it nearly impossible for anything, even light, to escape its grasp. The point of no return, known as the event horizon, is the point at which the escape velocity exceeds the speed of light. Therefore, nothing, including light, can escape from a black hole once it has crossed the event horizon.
According to Einstein's theory of relativity, time slows down near objects with strong gravitational fields, such as black holes. As light is sucked into a black hole, its speed and trajectory are affected by the intense gravity, causing time to appear to slow down from an outside observer's perspective.
Yes, the speed of light remains constant in all directions near a black hole. However, the intense gravity of the black hole can cause light to appear to bend or warp its trajectory, giving the illusion of different speeds. Ultimately, the speed of light remains constant, but its path may be altered near a black hole.