Video

Transcript

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