It's getting dark in here as we talk to Roberto Trotta about Dark Matter and Dark Energy. These two subjects are some of the most mysterious in the world of physics, as yet unconfirmed, but the subject of much research. Roberto tells us what our best theories are at the moment and how we are testing our current understanding of these elusive concepts.

Mixtape

1) Wagner - Ride of the Valkyries

2) Bruce Springsteen - Glory Days

3) Lady Gaga - The Edge of Glory

4) Beethoven - String Quartet No. 4 in C Minor, Op. 18: I. Allegro ma non tanto

5) Jovanotti - Il più grande spettacolo dopo il Big Bang

6) Little Boots - Remedy