I recently watched a video that explained how, previously, the opinion was that falling into a black-hole meant one would be stretched and torn. Never to recover.
But a newer, more sophisticated, understanding is that there is a “preservation of information”, to the effect that were an advanced race to collect all the materials from a blackhole and somehow analyse them you could, in theory, be brought back.
This was referred to as a “preservation of information.” What on earth is “information”? I can’t seem to find any literature on this because I don’t really even know what I’m searching for.
Here’s a link to the video: https://www.youtube.com/shorts/4Wac52-NYNI
In: 1
> I recently watched a video that explained how, previously, the opinion was that falling into a black-hole meant one would be stretched and torn. Never to recover.
> But a newer, more sophisticated, understanding is that there is a “preservation of information”
These two ideas aren’t really in tension, and they’re both believed to be true.
I think the phrase you’re looking for is “conservation of quantum information” or just “conservation of information”. What this says is that as the state of a quantum (i.e. very small-scale) system changes over time, no information is created or destroyed. Now, where this gets tricky is that our actual measurements of quantum systems are imperfect, so it doesn’t mean that information can always be recovered. There are some important gaps in our understanding of what actually happens when you measure a quantum system (this is known as “the measurement problem”), so it’s a bit debatable what the precise implications are.
Anyway, close to a black hole, any kind of reasonably large object is going to experience tidal forces, because the gravity at one end of the object is much stronger than at the other end. So it is believed that if you went close enough to a black hole, you would get torn apart and die. Though it might be difficult to get so close to a black hole as they tend to be surrounded by stars and other objects that are in the process of being torn apart themselves.
The issue here is that if light can’t escape a black hole, then presumably we can’t know anything about what’s going on inside it. But if that’s the case, it would seem that the information has disappeared. So we have an understanding of quantum mechanics that tells us that information is conserved, and an understanding of black holes that tells us that they destroy information. This seems like a contradiction, but we really don’t know all that much about black holes, and it’s also considered very possible that quantum mechanics doesn’t entirely capture what happens under extreme gravity, so it’s not really that much of a contradiction. It’s more like we have two naive guesses about what happens to the information and they can’t both be true.
Latest Answers