I Black Hole Time Dilation: What Would an Astronaut See?

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An astronaut approaching a black hole would experience significant time dilation, perceiving the outside universe as moving rapidly while time for them appears normal. Upon crossing the event horizon, the astronaut would witness the black hole's evaporation due to Hawking Radiation, but would not have time to reach the singularity before this occurs. The external universe would appear to accelerate infinitely, making it impossible for the astronaut to view the distant future while falling toward the singularity. To observe the future of the universe, one would need to remain stationary near the event horizon, which is not feasible. Understanding these phenomena requires careful consideration of the coordinate system used to describe the astronaut's experience.
Will K
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So let's say an astronaut was being sucked into a black hole and was able to escape spaghettification and all the death a black hole brings. Since black holes bend space-time itself, the astronaut would experience a differen't time zone than an outside observer (time is relative). The astronaut would see time moving normally, but would see the rest of the universe in a fast forward. Black holes evaporate due to Hawking Radiation, so would the astronaut see the black hole evaporate before he even reaches it? Or would the astronaut experience the black hole in his own time frame, while the rest of the universe sees the black hole evaporate away?
 
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A hypothetical indestructable observer gets to meet the singularity shortly after they cross the event horizon.
A few minutes at most, but the view of the entire future of the Universe might be worth the thrills.
 
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rootone said:
A hypothetical indestructable observer gets to meet the singularity shortly after they cross the event horizon.
A few minutes at most, but the view of the entire future of the Universe might be worth the thrills.
Yes it would definatly be worth it : ) But in order to reach the singularity of a black hole you must pass the event horizon. The event horizon puts the external universe on an infinite speed to the astronaut. But due to Hawking radiation and dimming cosmic background radiation, the black hole is going to evaporate. This means that the black hole has a life span (as long as the universe is around for it). So the astronaut would see the outside universe speed up infinitely. So as soon as the astronaut passes the event horizon, they will be immediately "transported" to the evaporation of the black hole (final moments). So does the astronaut ever have time to hit the singularity, and see the observable universe?
 
No, it doesn't work that way. The only way to view the distant future of the universe is to remain stationary near the EH, which is impossible. You must choose your coordinate system carefully to understand what a free falling observer sees during his brief journey into the spaghetti factory. Keep in mind you achieve relativistic velocities as you free fall toward the singularity and the external universe appears redshifted as photons struggle to catch up with you. For further discussion see: http://casa.colorado.edu/~ajsh/singularity.html.
 
Chronos said:
No, it doesn't work that way. The only way to view the distant future of the universe is to remain stationary near the EH, which is impossible. You must choose your coordinate system carefully to understand what a free falling observer sees during his brief journey into the spaghetti factory. Keep in mind you achieve relativistic velocities as you free fall toward the singularity and the external universe appears redshifted as photons struggle to catch up with you. For further discussion see: http://casa.colorado.edu/~ajsh/singularity.html.
Ok, thanks :P
 
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