I'm at the Institute for Computational Cosmology at Durham University,
where they have simulated a universe.
JAIME SALCIDO: One of the main projects in the Institute for Computational Cosmology
is to simulate how galaxies form and evolve.
We do that from initial conditions after the Big Bang,
in cosmological terms,
and we simulate expansion of the universe,
the gravitational forces of matter,
the dynamics of the cosmic gas,
and the formation of stars and black holes.
And the aim of the project is to understand how galaxies form and evolve.
DR MICHELLE FURLONG: The simulation is 300 million light years per side.
So particles in the simulation are the size of a million Suns.
So that means a galaxy, say the size of our own Milky Way galaxy,
would be made up of around 10,000 particles.
We ran on 4,096 cores. It took 43 days to run.
I think I worked it once, it'd take something like 300 years to run
if you were to run it - if you were to be able to
fit it on a single laptop and run it in that time.
JS: The oldest light of the universe, the cosmic microwave background,
has the imprint of the distribution of matter in the universe
when it was very young. So we use the observation of this light
to use as initial conditions in our simulations
and we just let the gravity do the magic,
and everything evolves stars and galaxies as the ones we see in the universe.
MF: The universe is made up of dark energy, which is around 75%,
and dark matter, which is a little over 20%,
and baryons, ordinary matter, they only make up around 4%.
This is something that has been found observationally
but has not yet been explained from a theoretical point of view.
But even though we don't actually know what dark energy is
we can simulate it and include it in the simulations
because we understand its nature, to some extent.
JS: As theorists, one of the main aims is to reproduce the observable universe.
So one of the things really cool about the simulation
is that we can use it to predict some of the things
that can be observed with real telescopes.
So we talk to astronomers that use the latest telescopes
so they can test out theories with real observations.
TS: Thank you to everyone at the Institute for Computational Cosmology at Durham University.
If you want to know more about the EAGLE Project and their simulations,
links are on screen now.
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