The universe,

rather beautiful, isn't it?

It's quite literally got everything,

from the very big

to the very small.

Sure, there are some less
than savory elements in there,

but on the whole,
scholars agree that its existence

is probably a good thing.

Such a good thing that
an entire field of scientific endeavor

is devoted to its study.

This is known as cosmology.

Cosmologists look
at what's out there in space

and piece together the tale
of how our universe evolved:

what it's doing now,

what it's going to be doing,

and how it all began in the first place.

It was Edwin Hubble who first noticed
that our universe is expanding,

by noting that galaxies seem to be flying
further and further apart.

This implied that everything
should have started

with the monumental explosion

of an infinitely hot,

infinitely small point.

This idea was jokingly
referred to at the time

as the "Big Bang,"

but as the evidence piled up,

the notion and the name actually stuck.

We know that after the Big Bang,

the universe cooled down

to form the stars and galaxies
that we see today.

Cosmologists have plenty of ideas
about how this happened.

But we can also probe
the origins of the universe

by recreating the hot, dense conditions
that existed at the beginning of time

in the laboratory.

This is done by particle physicists.

Over the past century,

particle physicists have been studying

matter and forces
at higher and higher energies.

Firstly with cosmic rays,

and then with particle accelerators,

machines that smash together
subatomic particles at great energies.

The greater the energy of the accelerator,

the further back in time
they can effectively peek.

Today, things are largely
made up of atoms,

but hundreds of seconds
after the Big Bang,

it was too hot for electrons to join
atomic nuclei to make atoms.

Instead, the universe consisted
of a swirling sea of subatomic matter.

A few seconds after the Big Bang,

it was hotter still,

hot enough to overpower the forces

that usually hold protons
and neutrons together

in atomic nuclei.

Further back, microseconds
after the Big Bang,

and the protons and neutrons

were only just beginning
to form from quarks,

one of the fundamental building blocks

of the standard model of particle physics.

Further back still,

and the energy was too great
even for the quarks to stick together.

Physicists hope that by going
to even greater energies,

they can see back to a time
when all the forces were one and the same,

which would make understanding

the origins of the universe a lot easier.

To do that, they'll not only need
to build bigger colliders,

but also work hard
to combine our knowledge

of the very, very big

with the very, very small

and share these fascinating
insights with each other

and with, well, you.

And that's how it should be!

Because, after all,
when it comes to our universe,

we're all in this one together.