I never really understood what happened really when the guy fell inside it in Interstellar and how come he started seeing all those photos. I just accepted it as Hollywood bs.
I know my question is based on a movie but would still like to know what will someone witness (assuming of course they somehow live)
Black holes were sometimes called "frozen stars", because time slows down at the event horizon to a stop. If light could escape from black holes and somehow the material continued to emit/reflect light despite time being stopped for it, then as outside observers, what we would see is the star at the moment it collapsed to the size of its event horizon. Though if you entered the event horizon, from your point of view you would see time progressing again inside.
An object falling into a black hole would often go through the process of "spaghettification", being pulled apart because the gravity from the black hole on the close side of the object would be immensely stronger than the gravity on the far side of the object. Though It's possible for a black hole to have an event horizon large enough that the point where spaghettification is beyond it; I think Interstellar had some line to imply that about their black hole.
>I never really understood what happened really when the guy fell inside it in Interstellar and how come he started seeing all those photos. I just accepted it as Hollywood bs.
In the movie, it was supposed to be that the same aliens (well, future humans) that had constructed the original wormhole had also connected another wormhole inside the blackhole. On the inside of the second wormhole, they brought him into a constructed environment to use him as a tool to encode a message to the past to himself that would be able to get him to arrive here in the first place. I think the vague idea of the future-humans was that they used the spacetime-warping nature of the black hole to somehow transcend space and time in our future, but as a nearly one-way trip: they could only interact with our universe / the past through warping gravity (vibrations or making wormholes), and inside the black hole, they had more freedom to do this, and they used that to make the interface for the main character. (Story-wise, I think it seems like good contrivance to allow the mysterious benefactors that ability to give some help, but without being able to do everything and still allow the relatable modern human characters to do all the interesting detail work.)