They are massive, and extremely dense.
They rip apart anything and everything
that gets close to them.
We can't see black holes.
But we know they have the destructive power
to wipe everything out of existence.
This is WHAT IF,
and here's what would happen
if a black hole deleted the Universe.
Before we get to the part
where a black hole erases the Universe,
let's make something clear.
The Universe is a giant supercomputer
processing information.
Without information, there can be no Universe.
In physics, information is the property of a specific state of a particle.
I know, it sounds confusing.
Here's a simpler way of looking at it.
This is a carbon atom.
A bunch of these can be arranged to make a hard diamond.
But if you change the arrangement of atoms,
you can get soft graphite.
The basic building blocks are the same.
It's information that makes them different.
In quantum mechanics, information is like energy -
it can't disappear into nothingness.
So how in the Universe can one black hole do the impossible?
Black holes act like monstrous cosmic trash compactors.
They squeeze stars, planets
and unfortunate astronauts who crossed the event horizon
into a microscopic point.
So what happens to the information
about every particle that a black hole consumes?
Since information can never be destroyed,
it has to be stored somewhere inside that black hole, right?
Our original understanding of black holes assumed that
everything that disappeared in the black hole,
stayed in the black hole.
The moment an object passed the event horizon,
it got crushed into the density of the black hole.
The information about it could never be retrieved again.
That's what we thought
before Stephen Hawking introduced Hawking radiation.
Hawking realized that black holes aren't static.
Rather, they release their mass and energy back into the Universe
particle by particle, until there is nothing left.
So, does that mean the information within a black hole
can somehow escape with the black hole's outgoing radiation?
Not quite.
The black hole doesn't preserve the information it consumes.
It chaotically mixes it together with other bits of information,
making it impossible to recover.
If the information can be lost,
that would mean that black holes can eventually delete the Universe.
Forever.
But there is a possibility that the black hole doesn't delete the information.
It may be hiding it in a baby universe -
a small self-contained part of the universe that branched off of ours.
The information wouldn't technically be lost,
but we wouldn't be able to interact with it.
Another possibility is that black holes can encode the information,
according to the holographic principle.
If you were to get trapped inside a black hole,
you'd still experience three-dimensional space.
For us looking at you from the outside,
you'd appear stretched on the flat surface.
Just like a hologram.
That would mean that the information paradox is resolved,
and we don't need to rewrite the laws of physics.
But we'd have to rethink our understanding of reality.
The Universe could be a 3D image projected off a 2D surface.
And you may be a hologram on the surface of a black hole.
And the best part -
the black hole couldn't delete the Universe after all.
Wait, how can we be living in a hologram?
Well, that's a story for another WHAT IF.