Black Hole Time Dilation: What Would an Astronaut See?

In summary, 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?
  • #1
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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  • #2
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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  • #3
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?
 
  • #4
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.
 
  • #5
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
 

1. What is black hole time dilation?

Black hole time dilation refers to the phenomenon in which time appears to slow down for an observer near a black hole. This is due to the intense gravitational pull of the black hole, which warps space-time and causes time to pass more slowly.

2. How does black hole time dilation affect an astronaut?

If an astronaut were to approach a black hole, they would experience time passing at a slower rate compared to someone far away from the black hole. This means that while a few hours may pass for the astronaut, years could have passed for someone on Earth.

3. Can an astronaut survive entering a black hole?

No, an astronaut would not survive entering a black hole. The intense gravitational pull would cause them to be stretched and torn apart in a process called "spaghettification". Additionally, the intense radiation near a black hole would also be fatal to a human.

4. Does the size of the black hole affect time dilation?

Yes, the size of the black hole does affect time dilation. The larger the black hole, the stronger its gravitational pull and the more significant the time dilation effect will be.

5. Is time dilation the same for all objects near a black hole?

No, time dilation can vary for different objects near a black hole depending on their distance from the event horizon (the point of no return) and their velocity. Objects closer to the event horizon or moving at high speeds will experience more extreme time dilation compared to those further away or moving at slower speeds.

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