Only in a local free falling frame, not in non-inertial coordinates.Jur van Oerle said:If light always travels at the speed of light...
I don't know what any of these words mean :PA.T. said:Only in a local free falling frame, not in non-inertial coordinates.
I think I understand better now, light does not travel slower but instead, the distance it has to travel is infinite because the space around the light particle is curved.CentrifugalKing said:Light travels in a straight light. Under heavy gravitational forces, light will curve. Black holes bend spacetime. So no matter what path the light goes, it'll bend back at the center.
No, it will hit the center. Every direction, every possible velocity and acceleration leads to the center, it is impossible to avoid hitting it.Jur van Oerle said:Hi @mfb ,
thank you for your reply. I still don't fully understand; do you mean that light will orbit the center of the black hole?
phinds said:Right at the Event Horizon, if any light were generated by a photon-producing process, the resultant photon, if headed away from the singularity, can be traveling outward at c as measured locally, but as has been said, spacetime is "bent" in gravitational fields and it happens that at the Event Horizon (because of the definition of the Event Horizon) the bending is exactly equivalent to c so from the reference point of observer outside the BH, that light "appears" (actually it would be more correct to say "is calculated as being" since you can't really see it) stationary at the EH.
At every point inside the EH, the light follows the local geodesic back to the center of the BH so light at the EH cannot have been created inside the EH because such light can never reach the EH. It cannot be generated outside the EH because such light will be traveling inward when it reaches the EH and thus will inevitably travel further inward to the singularity.
I think there are more complex situations and @mfb I would appreciate your comments on what I have just said.
"bending" is a very poor description of what is going on. It is a term that we use because we humans have evolved in a world that is to all of our senses classical rather than quantum or cosmological, and we have an innate bias towards Euclidean geometry since that was how we survived. Believing, for example, that one could throw a spear at some animal you hope to eat and expect the spear to follow a Riemann geometry path (even assuming cavemen knew what Riemann geometry was, which they did not) would lead to starvation.Jur van Oerle said:Thanks.
This is the most detailed response to my question and I think I understand it and the answer to it better. Some thing are still vague though, like what you mean by bending space-time and why that is any different from throwing a ball and watch it fall down to Earth (or any other object exerting enough gravity).
The event horizon is a null surface, meaning that locally it is moving at the speed of light. If you flash two pulses of light from some emitter then the surface defined by the first flash also "traps" the light from the second flash, even in flat spacetime. Also, even in flat spacetime if you accelerate constantly in some direction then there will be light pulses that are "trapped" in the sense that they cannot ever reach you.Jur van Oerle said:how can a black hole "trap" light if this speed cannot change?
Jur van Oerle said:how can a black hole "trap" light if this speed cannot change?
The intense gravity of a black hole is caused by the massive amount of matter compressed into a tiny space. This gravity is so strong that it warps the fabric of space-time, creating a region of no escape called the event horizon. When light approaches the event horizon, it gets pulled in and cannot escape, thus getting trapped in the black hole.
Yes, any form of electromagnetic radiation, including visible light, X-rays, and radio waves, can be trapped in a black hole. The only way for light to escape a black hole is if it is emitted from outside the event horizon.
No, it is not possible for light to escape a black hole once it has crossed the event horizon. The intense gravity of the black hole bends the path of light in such a way that it cannot escape.
The size of a black hole directly affects its ability to trap light. The larger the black hole's mass, the stronger its gravity and the larger its event horizon. This means that a larger black hole can trap light from a greater distance compared to a smaller black hole.
Yes, light can be emitted from a black hole, but only from outside the event horizon. When matter falls into a black hole, it heats up and emits radiation, including light. This is known as Hawking radiation and is one of the few ways that information can escape a black hole.