• abomination
In summary, the conversation discusses a hypothetical scenario where two individuals orbit a black hole, with one eventually falling towards it. The individual who stays in orbit observes the other's time slowing down and their speed increasing due to the stronger gravitational field. Meanwhile, the individual falling towards the black hole observes the other orbiting for a longer period of time due to the slow rate of Hawking's Radiation. This raises the question of when the outside observer would see the Hawking radiation, as nothing ever crosses the event horizon.
abomination
A thought experiment:
Say that you and I decide we are going to go into orbit around a black hole. I am brave and you are weak, so I decide I'm going to take the plunge and you just stay in orbit. As I fall toward the black hole, the strength of the gravitational field increases, and time for me slows down relative to you. So I see your orbiting speed increase. Meanwhile, you are orbiting the black hole, and see the Hawking's Radiation slowly decreasing its mass. You count the number of times you orbit the black hole before it loses so much mass that you escape the orbit: say it's 100 billion times. However, I am observing you from right next to the black hole, and for me Hawking Radiation is happening just as slowly as it is for you. At some point your speed gets so large and time goes on long enough that I see you orbit the black hole 100 billion times. However, the black hole's mass has not decreased that much (since for me it has only been a little while for you to orbit that long, so Hawking Radiation has done little), and so you continue to orbit after the 100 billion orbits.
So, at the end there are two yous: from your point of view you leave orbit after 100 billion orbit, and from my point of view you continue orbiting long after that.
How is this resolved? I asked my professor and he had no idea.

Hopefully this won't hijack the thread, but I have somewhat related mystery about Hawking radiation that I haven't found a solution for. That is, for a spherical, non-rotating, black hole, for sure, an outside observer never observed matter or energy reaching the event horizon (ever so close, but never reaching, let alone crossing). At what point does the outside observer start to see Hawking radiation? Especially, as 'vernacular' derivations involve virtual photons crossing the horizon; but nothing ever crosses according the the outside observer.

The "GR/Hawking Radiation Contradiction" refers to a disagreement between two theories in physics: General Relativity (GR) and Hawking Radiation. General Relativity is a theory that describes the force of gravity and how it affects the large-scale structure of the universe. Hawking Radiation, on the other hand, is a theory proposed by physicist Stephen Hawking that suggests black holes emit radiation and eventually evaporate. The contradiction arises because these two theories seem to contradict each other, as black holes are predicted by both theories but their behavior is described differently.

Currently, there is no definitive answer to the "GR/Hawking Radiation Contradiction." Some scientists believe that a unified theory of physics, such as string theory, may be able to reconcile these two theories. Others suggest that the contradiction may be due to our limited understanding of these phenomena and that further research and experiments are needed to resolve it.

## How does General Relativity explain black holes?

General Relativity explains black holes as regions of space with such strong gravitational pull that even light cannot escape. It states that when a massive star dies, it collapses under its own gravity and forms a singularity, a point of infinite density and zero volume. The singularity is surrounded by an event horizon, the point of no return, where the escape velocity exceeds the speed of light.

Hawking Radiation suggests that black holes emit radiation and eventually evaporate, while General Relativity predicts that nothing can escape a black hole, not even light. This contradiction arises because General Relativity is a classical theory that does not take into account quantum effects, while Hawking Radiation is based on quantum mechanics. This discrepancy between the two theories has yet to be resolved.

## What are the potential implications of resolving the "GR/Hawking Radiation Contradiction"?

If the "GR/Hawking Radiation Contradiction" is resolved, it could lead to a better understanding of the fundamental laws of the universe. It could also have practical applications, such as improving our ability to predict and study black holes, which could have implications for space travel and communication. Additionally, resolving this contradiction could help bridge the gap between classical and quantum physics, leading to a more unified theory of physics.

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