The ATLAS experiment is a huge particle physics detector which is situated near Geneva, Switzerland in the largest man-made, underground cavern in Europe. The detector is barrel shaped and layered like an onion which each layer collecting data about the particles passing through it.

The Large Hadron Collider runs through the middle of the detector and is arranged such that the two beams of protons, each with as much energy as a high speed train, collide in the centre. Fortunately only a tiny fraction of the particles in each beam collide, about 20 once we reach full design specifications, and each collision produces hundreds of different types of particles which spread out from the collision into the detector.

This type of collision is what happened everywhere in the very early universe, about one trillionth of a second after the Big Bang so by studying the physics of these collisions we gain a better understanding of why the Universe is the way we observe it today as well as getting a better understanding of fundamental physics.

Such fundamental physics may seem removed from everyday life but historically such knowledge has lead to incredibly useful innovations. For example semiconductors, which are the basis for all modern electronics, rely on our understanding of quantum physics: the particle physics of 100 years ago. Already knowledge of particle physics, accelerators and detectors is being put to use in the medical profession to improve imaging of patients as well as to treat cancer.