30.1 The Subatomic World

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Sometimes you have to think big to find something really small.  Deep underground, underlying the border between Switzerland and France, is a gigantic scientific instrument called the Large Hadron Collider (LHC).  The LHC is the biggest machine in the world, is nearly 27 km in circumference and contains 9300 magnets along a circular path.  When the LHC operates at full power, trillions of protons travel its circumference 11 245 times every second - nearly the speed of light!

Coming in the opposite direction and at the same speed, a second group of protons collide with the first group of photons such that 600 million collisions should occur every second with energies that will produce temperatures 100 000 times that of the Sun's core.  

If the LHC sounds impressive, that's because it is!  With these energies, never before seen on Earth, the protons will break apart, revealing their subatomic world.  The products of such a high-energy collision should help scientists answer some unresolved questions such as the following:

• What is the origin of mass?  What makes up the mass in a nucleon?

• What makes up 96% of the universe?  What is dark matter?

• Where is antimatter, as predicted by the standard model of the atom?

• What happened in the first few seconds of the universe?

• Are there other dimensions in the space-time continuum?

The LHC was built to provide enough energy to try to answer questions like these and to fill in the knowledge gaps that still exist in our understanding of the universe beyond our planet and reveal the fundamental make-up of the subatomic universe. 

© CERN 2008. Used with permission.

The Large Hadron Collider is the world's most powerful machine. It is 27 km long and is buried 100 m below the border of Switzerland and France.