Black Hole; Gravity & Speed Within Questions

In summary, the conversation discusses the behavior of photons near a black hole's event horizon and within the singularity. It is determined that photons cannot float or hover due to their constant motion, and the exact behavior of objects crossing the event horizon and entering the singularity is still a topic of debate and research.
  • #1
KevinMWHM
27
0
2 questions;

Is there a point, either at or just beyond the event horizon where a photon would "float" due to an equal amount of gravity vs the energy of the photon trying to "avoid" said gravity? Does this affect any relativity laws if there is a brief moment where a 3rd frame of reference could possibly see a "motionless" particle of light?

For an object that crosses the event horizon, does it's velocity increase at any kind of fixed rate, thus smashing into the singularity? Or does the effect of gravity on the objects frame of time cause it to slowly "blend" into the singularity?

If the 2nd question is hard to answer because of a lack of knowledge within black holes, what are some of the larger theories regarding what is happening at the center, if there are any?
 
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  • #2
not fish-like

KevinMWHM said:
Is there a point, either at or just beyond the event horizon where a photon would "float" due to an equal amount of gravity vs the energy of the photon trying to "avoid" said gravity? Does this affect any relativity laws if there is a brief moment where a 3rd frame of reference could possibly see a "motionless" particle of light?

Hi KevinMWHM! :smile:

No, a black hole is not like a waterfall: the speed of light cannot "match the speed of space" in the way a fish could match the speed of a waterfall.

Photons always move, they can't float. :wink:
For an object that crosses the event horizon, does it's velocity increase at any kind of fixed rate, thus smashing into the singularity? Or does the effect of gravity on the objects frame of time cause it to slowly "blend" into the singularity?

I can't remember the exact formula, but a photon will hit the singularity within a very few wavelengths.
 
  • #3
Hi Tim, Thanx for the link,

So in regards to my first question, would I be correct in relating it to the radius of photon sphere in that a photon, always being in motion, could never be in the scenerio I depicted?thanks also for the answer

-kevin
 
  • #4
KevinMWHM said:
Hi Tim, Thanx for the link …

ah, that's an autolink … a unique PF feature! :biggrin:
So in regards to my first question, would I be correct in relating it to the radius of photon sphere in that a photon, always being in motion, could never be in the scenerio I depicted?

Yes, a photon can't hover, it can only keep the same "height" by moving "sideways". :smile:
 

1. What is a black hole?

A black hole is a region in space where the gravitational pull is so strong that even light cannot escape from it.

2. How is a black hole formed?

A black hole is formed when a massive star collapses in on itself due to its own gravity. This collapse causes the star's density to become infinitely high, creating a singularity at its center.

3. How does gravity work within a black hole?

Within a black hole, gravity is extremely strong due to the massive amount of matter located in a small area. The gravity is so strong that it warps space-time, pulling everything towards the singularity at the center.

4. Can anything escape from a black hole once it has been pulled in?

No, once an object has passed the event horizon of a black hole, it cannot escape. The gravitational pull is too strong for anything, including light, to escape.

5. How does speed play a role in black holes?

Speed is an important factor in black holes. The closer an object gets to the event horizon, the faster it needs to travel in order to escape the gravitational pull. This is known as the escape velocity and is dependent on the mass of the black hole.

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