How to fit the Universe
in your computer?

and is it actually useful?

and do we actually do it?

Dr. Corentin Cadiou

University College London
@cphyc

Do

We

Even

Need

Simulations?

Do

We

Even

Need

Simulations?

We'll never see a galaxy evolving!

We'll never see a galaxy evolving!

… so how can we know things evolve?

???

↑That's me

no problem.

Do

We

Even

Need

Simulations?

We'll never see a galaxy evolving!

… so how can we know things evolve?

⇒ Yes!

Do

We

Even

Need

Simulations?

Create a Universe in a computer

... to understand the real one!

/!\ Background not a real simulation!

How to simulate the Universe?

  1. Create a box for space and time
  2. Include known physics*
  3. Set some initial conditions**
  4. Move time forward
  5. ☕☕☕☕☕🍺🛌
  6. SCIENCE !
    • Compare to observations
    • Make predictions

* Gravitation / chemistry / stars / black holes / dark matter / …

** As given by the cosmic microwave background

Each bright dot is one galaxy

?

HST

Simple example

Merger of the Milky Way (our own galaxy)
with Andromeda [in a few billion years]

NASA; ESA; and F. Summers

NASA; ESA; and F. Summers

Our whole universe was in a hot, dense state (and homogenous)
Then nearly fourteen billion years ago expansion started, wait
[...]
That all started with the big bang! Hey!

The large scale structure of the Universe

Galaxies do not appear anywhere in the Universe…

…they form a "cosmic web"

Obelisk simulation — Own work

Forming a spiral galaxy...

New Horizon simulation — IAP, CNRS

We can fit the Universe in a computer!

→ insight on actual Universe

→ better understanding of physics

very nice images!

Questions?

50 million light year

1 million light year

100,000 light year

How to fit the Universe in your computer?

By Corentin Cadiou

How to fit the Universe in your computer?

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