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Did you know that Arnold Schwarzenegger is a billionaire?
On our podcast, Good Bad Billionaire,
we explain how the wealthiest people on the planet became so incredibly rich.
And we're back with a new season and the story of one of Hollywood's biggest stars.
He was famously a bodybuilder, a movie action hero, and even governor of California.
But Arnie made even more money from another career.
Find out exactly how Arnold Schwarzenegger became a billionaire by listening to Good Bad Billionaire.
That's Good Bad Billionaire.
Listen wherever you get your BBC podcast.
So we've just walked into this massive airplane hangar looking space and
if we look down what can we see?
At the moment there is a concrete floor or ceiling above the experiment.
Welcome to Crowd Science from the BBC World Service, the show that answers your science questions.
It's about 60 metres below ground level, so we look down and below this floor is the experiment.
So sort of down this massive shaft.
We're visiting somewhere that's been on my bucket list for a very long time.
The world's biggest particle physics laboratory, CERN, home of the Large Hadron Collider.
And why is there such a massive layer of concrete?
The concrete is to stop any particles from escaping from the accelerator or from the collisions.