What if our universe
comes with a self-destruct button
to eliminate itself
so cleanly and efficiently,
that every single physical thing
would just stop existing
and life would be impossible
forever.
The ultimate ecological catastrophe -
vacuum decay.
(Theme music)
To explain how our universe
could destroy itself,
we need to understand two principles:
One - energy levels.
A core idea in physics is that
everything has an energy level.
The higher the level, the more energy is in the system
Wood, for example, has a high level.
It can be burnt, a process that
releases the chemical energy stored in its molecular bonds
and turns it into heat.
The ash leftover is at a
lower energy level than the wood before.
Two - stability.
Everything in our universe tries to move
towards its ground state, in which it's completely stable
and has as little energy as possible.
For example, a ball on a hill is unstable
and has a lot of potential energy.
When disturbed, it will roll down into the valey
and lose its potential energy in the process
The ball is now in its ground state and stable.
It will remain like that.
Everything in our universe
follows these two principles.
If something has a lot of energy,
it's unstable and wants to get rid of it
to become stable
and reach its ground state.
This is true for every system
even in the weird world of
quantum mechanics.
If our current understanding of physics is correct, then the universe
gets its properties from quantum fields.
We explained them in detail
in another video.
For this video, imagine them
as the rules of the universe.
They tell particles how to
behave and interact
Like everything in the universe,
they want to be in the lowest energy level possible,
which is called a vacuum state.
This has nothing to do with
vacuum in space.
It's just called this way
because scientists are bad at naming things
We then call the fields reached their
vacuum state, except maybe one.
It's possible that the Higgs Field
is not stable, but metastable, which is
a fancy way of saying that it
pretends to be stable but really is not.
It would be a false vacuum.
The Higgs Field is responsible for
giving particles their mass,
which rules how almost everything
in the universe interacts.
What would happen if the Higgs Field is a false vacuum?
Think of our ball in the valley:
the ball is the Higgs Field.
The valley might not be the lowest energy state for the Higgs Field.
There might an even deeper valley that it wants to get to.
This would mean that the Higgs Field has a lot of potential energy,
waiting to be released.
The Higgs Field could be like a piece of wood
but drenched in gasoline,
waiting to set the universe on fire.
A random spark like quantum tunneling
could release the potential energy
of the Higgs Fields.
This could happen at any time
and without warning.
If at any point in space,
this so-called vacuum decay starts,
there is no turning back.
As the Higgs Field crashes into
the lower energy state,
it releases a massive amount of
potential energy.
This energy pushes the space around it
over the barrier, which releases
more potential energy.
A sphere of the new stable Higgs Field,
or true vacuum, grows at the
speed of light in all directions.
Imagine it like setting a sea of gasoline,
the size of the universe, on fire.
This sphere is surrounded by
a shell of energy that devours everything
it comes into contact with.
Whatever it touches
is eliminated for existence.
The bubble will continue to grow forever.
deleting the universe on its way.
There is no way to be warned,
since it's so fast.
But there's nothing we can do anyway.
Our destruction would be instant,
in a fraction of second,
Earth would be gone.
But it actually gets worse.
If the energy level
of the Higgs Field changes,
it changes all of physics.
In the true vacuum of the sphere,
the standard model will be overthrown,
superseded by different physics
that we don't know -
how fundamental particles behave,
how atoms hold together,
how chemicals react.
Vacuum decay won't just destroy life,
it will destroy chemistry itself,
making life as we know it impossible.
We simply have no idea
what it would be like inside.
It might be a shadow of what it is now,
or not.
We don't know.
If vacuum decay happens,
the outlook is indeed grim.
If you feel slightly worried now,
don't be.
At this point, false vacuum is speculation
based on our current understanding of
particle physics, which might be wrong.
It's kind of like using a ruler
to measure a continent.
(playful music)
Sure, you can do it, but you might be off
by quite a bit at the end.
Right now, no-one can say a vacuum decay
is a thing that's real
or just a scary idea.
But even if one or multiple spheres
of death have already started expanding,
the universe is so big
that they might not reach us
for billions of years.
If they're far enough away,
they might not ever be able to reach us
because of the expansion of the universe.
The speed of light is not that fast
on the scale of the universe.
So, while vacuum decay is
fascinatingly scary,
right now, there are other things
we should be more afraid of.
In contrast to vacuum decay,
we have the power to prepare
for most of them.
Videos like this one
take hundreds of hours to make, so
support us on Patreon
if you'd like to learn more about
the destruction of everything.
It really helps us out.
We tried to destroy the universe
at least once every few months.
So let us know in the comments,
if you have doomsday scenarios
you would like us to cover.
Subtitles by the Amara.org community