Questions about Black Holes: Can Objects Survive? Can Light Go Through?

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SUMMARY

This discussion focuses on the nature of black holes and the behavior of objects and light in their vicinity. Participants clarify that no object, regardless of size or density, can withstand the gravitational pull of a black hole once it crosses the event horizon. Light, composed of massless photons, cannot escape a black hole due to the warping of spacetime, which dictates that all trajectories lead to the singularity. The conversation emphasizes that black holes do not "pull" objects but rather curve spacetime, compelling particles to follow geodesics that ultimately lead to destruction at the singularity.

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  • Understanding of general relativity and spacetime curvature
  • Knowledge of black hole physics, including event horizons and singularities
  • Familiarity with the properties of light and photons
  • Basic grasp of gravitational forces and escape velocity concepts
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Astronomy enthusiasts, physicists, and students studying astrophysics who seek to deepen their understanding of black holes and the fundamental principles of gravity and light behavior in extreme environments.

RustyBullet
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Hey guys. I have a few questions about black holes.

First. Is it possible for there to exist a big enough object in space that wouldn't be destroyed by a black hole ? Black Holes have gravity so strong that they destroy any object that comes near it. But, if there was a big enough object, would it be possible for the Black Hole to not be able to destroy it, thus the object actually go through the black hole ? Or maybe even have it's own gravity exceed that of the Black Hole, and have the Black Hole sucked in ?

Second. Black Holes have a gravity so strong that even light is sucked in. But I'm thinking... light doesn't have weight, and even if it could be ripped apart (by the Black Hole's gravity), it wouldn't cease to exist.. the light would still be visible, only in many specks of light.
So what I'm asking is, would'nt light go through the Black Hole, and be still be visible when it reaches the other side ?

Thanks =]
 
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Even the light responds to gravity. For example a box with a perfect mirror has more gravitational force when it has a lot of photons inside.
Photons in black hole will be attracted to the center of BH and will join the pure mass or pure energy party. In there they loose their past and become a pure tiny thing of volume almost zero or zero. But the overall charge and mass will be preserved.
 
First question:

For an object to be able to withstand the strong gravitational force of the black hole, it will have to be incredibly dense, more so than anything we have seen thus far. The closer this object gets to the singularity of the black hole, the stronger will the gravitational force be, but what happens when an object enters the singularity is unknown, but many believe that anything that will enter the singularity will be instantly destroyed. Remember that these are just theories since we do not have the scientific skill, nor the resources to get any type of proof.

Second question:

Many people, when they hear the phrase that light won't escape, think that light does not have mass, but light is made out (as you probably know) by photons, which is matter. Light is photons, that is moving at extremely high speeds. So in all sense, the Black Hole doesn't bend light itself, it bends matter which light is made of.
 
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Division said:
light is made out (as you probably know) by electrons

I'm afraid that's not so.
 
Vanadium 50 said:
I'm afraid that's not so.

Corrected it.
 
I don't think this is any clearer.

Division said:
So in all sense, the Black Hole doesn't bend light itself, it bends matter which light is made of.

Huh?

I am sorry about the way this sounds, but I can't seem to phrase this in a way that doesn't sound so harsh, and I apologize. But do you know what you are talking about here?
 
Division said:
Many people, when they hear the phrase that light won't escape, think that light does not have mass, but light is made out (as you probably know) by photons, which is matter. Light is photons, that is moving at extremely high speeds. So in all sense, the Black Hole doesn't bend light itself, it bends matter which light is made of.

umm, photons do not have any mass. The reason why light is affected by black holes/gravity in because of warping and curving of space - gravity is not thought to be a vector like force. Photons follow the "surface" of space-time. If curving is extremely strong as is the case with black holes, light won't be able to escape it
 
the escape velocity of the black hole is greater than that of speed of light 3X10^8 ms^-1, so when light gets caught in the black hole there is no chance for it to get out
earth has an escape velocity of 11.2km/s just to let you know !

:wink:
 
Could some black holes be a vaccumm held open by matter and energy, surounding it?
 
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  • #10
No, that bears no resemblance to what black holes are.
 
  • #11
Could some black holes be vaccumms held open by surounding matter and energy.
 
  • #12
sorry I guess I'm confusing black holes, with a vortex. That holds open a vaccumm, light can not enter.
 
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  • #13
A compact body curves the spacetime in its vicinity.In General relativity,there arent any forces.The gravitation is directly feature of curved spacetime.So mass curved spacetime and particles have to move in geodesics.Geodesics are shortest paths in spacetime.
If a body collapse under its gravitaion and when it reaches Schwarzschild radius it become a black hole.Blackholes don't pull the particles or photon.They curved the spacetime and so trajectories of any particles must follow the geodesics.And these geodesics are created by black hole.The paths of particles end up in real singularity.But when particle or photon cross the event horizon(Schwazschild radius) they can't come back.They don't escape.
 
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