Water left out in the sun, evaporates.Gasoline
evaporates.
And black holes!
Yep.
They do too.
Hi there you little quantum wiggles in space-time,
Trace here for DNews!
First things first, make sure you’re sitting
down for this episode, things are about to
get deep.
Like a supermassive black hole’s gravitational
well “deep”…
So, black holes.
I think most of us have a pretty good idea
about what a black hole is, even if we don’t
necessarily understand , you know, what it is, you
know what I mean.
Black holes are basically regions in the universe
where physics flips us the bird and takes
a holiday.
They are regions that are so dense with matter
that their gravity becomes so strong that
even light cannot escape and the normal laws
of physics no longer apply.
They're made of two things: a dense, massive
singularity and an “event horizon,” which
is basically the point of no return where
gravity gets so high nothing escapes.
We will never know what lies between the event
horizon and singularity (unless you’re Matthew
McConaughey I guess) as no information
can escape past the event horizon.
If you looked in, you’d be forever lost
from the universe inside the who-knows-whatness
that lies beyond.
However, in recent decades, physicists have
been debating the possibility that information
can escape from a black hole via something
called Hawking Radiation, which throws a curveball
for the “classical” model of black hole
physics.
British physics superhero Stephen Hawking
started playing with this idea in the 1970s.
He came to the conclusion that not only can
information escape the black hole’s clutches,
it can also carry mass away from the black
hole.
Black holes that aren't gaining mass, will
eventually lose it and disappear -- or evaporate.
Basically, this information is just electromagnetic
radiation, like light.
It's called "information" because it's encoded
with information about what has fallen beyond
the event horizon into the black hole!
Something we know nothing about.
So, taking this to its logical conclusion,
black holes are not permanent features in
the cosmos!
Because if they’re not sucking in matter,
they slowly evaporate and eventually disappear!
This works because the vacuum of space isn't
really a vacuum.
We just did a video about how virtual particles
pop in and out of existence.
It's a quantum mechanics thing, and it's complicated
-- so just know they do this, and that they do
it in pairs.
Those pairs pop into existence, and then hit
each other and disappear -- this is called
“annihilation”.
This is good, because energy cannot be created
or destroyed, and the math must balance.
Because they annihilate, they don't break
any law! QUANTUM LAWWWWW!
I just love doing that.
Sometimes, these pairs will appear in that
no-man's land between the event horizon and
the singularity of a black hole.
In this situation, theoretical physicists
think that one of the virtual particle pairs
should fall into the black hole, while the
partner of the pair is stuck on the other
side on its lonesome.
We'll call this lonesome particle Jared.
This is where things get interesting.
According to quantum dynamics, that lonesome
Jared particle is now stuck in our universe!
It becomes “real” so it can't disappear
again!
It's no longer "virtual".
It’s gifted with a mass and energy, like
Pinnochio turning from a wooden toy into a
real boy.
But to conserve energy (another pretty heavy
physics law that has to be obeyed!), the virtual
particle that fell into the black hole must
carry some kind of negitive energy, therefore very
slightly reducing the amount of energy inside that black
hole.
The net effect is that the Jared particle
(like a photon of radiation) is sent out of the
black hole into space, and the black hole
loses a little bit of mass.
If this is continuously happening and a black
hole is no longer eating new mass, it will
lose mass overall.
This is called "evaporating."
Scientists are currently looking for the gamma-ray
signal that would be generated each time one
of these black holes pop out of existence.
Though we've never seen it happen, yet.
Also, scientists at the Large Hadron Collider
are looking to create ultra-tiny micro black
holes, which would fizzle out of existence
really fast, helping us better understand
this evaporating process.
Though Hawking Radiation is fun to consider,
it has added fuel to the epic battle between
general relativity and quantum dynamics, culminating
in the “black hole firewall paradox”!
But we probably should save that for another
day...
Speaking of the Large Hadron Collider, we
visited this crazy particle accelerator to
give you an inside look. Check it out.
How's your brain feeling after all of this? A little stretched? A little tough?
Let us know down in the comments if you want us to do more of these
videos and keep watching so you get more DNews.
