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Simulations back up theory that Universe is a hologram(r/Physics)

How much information could you put in a given volume of space? You could write the information on DVDs, or blurays, and clearly you could fit quite a lot of information. Not only that, but obviously if you double the volume of space available, you could fit twice as many blurays in that volume, and thus double the amount of information in that space.

So intuitively, the volume of space is proportional to the maximum amount of information that you can put in that space.

But, let’s consider further. Presumably we could one day do better than bluray, so what’s the upper limit? At what point could we truly not get any more information into a space?

Aha! A black hole!

We surely can’t do better than a black hole! So, let’s make a black hole that exactly fits the given volume. The amount of information in that black hole is the maximum possible amount of information in that volume.

But now say that we double the volume available. How much information do we need to add to the black hole to make it grow to fit that new volume? Double?

Strangely.. no. The amount of information in a black hole is proportional to its **area**, not its **volume**. Why? Basically because information cannot be destroyed. So there can’t be any information *inside* the black hole since everything inside the black hole is destroyed! So that must mean that all the information that you threw into the black hole is actually on the surface! (See the book reference at the end for a long discussion on this. Arguments over this point were called the “Black hole wars”, and it has long and very interesting history).

So wait, what does this mean? The maximum amount of information that can fit in a given region of space is proportional to the area of the boundary of that space!? Not the volume!?

This is getting weird.. so let’s give it a strange name analogous to something else that encodes 3D volume information in a 2D plane – holograms. Now lets sensationalise the title a bit, and viola – the universe is a hologram.

Okay, at this point I’ve only explained the background, and not this new research.. honestly I’ve got quite a bit of journey to go to show that we can now explain why that (the information in a 3D volume is proportional to its 2D boundary) can be mapped to analogously to a 10 dimension space… and I’d probably get it wrong. (Interesting point – you can prove why using string theory, without actually assuming that string theory is correct. Again see book below)

If anyone is interested in learning more and getting the answer from Susskind himself, read his book on the topic – The Black Hole War. You can get (cough) an audio book version. It’s an easy read (pop science) and lots of fun.

Edit: Updated to give an explanation for information being encoded on the surface of black holes