Quark-Gluon-Plasma at Brookhaven and CERN

Sammanfattning: For thousands of years we humans have asked ourselves the same question; what does our universe consist of and how does it work? One step in the direction to solve this mystery is to understand how the universe behaved just a few fractions of seconds after Big Bang. It is today believed that the matter present at this time consisted of a so called QGP. This is a kind of matter where the quarks and gluons are free from each other. If we can understand the QGP we might understand more about the laws of our universe. This thesis is an easy-to-read introduction, appropriate for physicists not specialized in high energy physics, where I have gathered information to give a brief insight in subject QGP. The first few chapters contain general particle physics with a special weight towards the quarks, gluons and the strong interaction. Also proton-proton-collisions, nucleus-nucleus-collisions and their role in the hunt for QGP are discussed. In the latter chapters the discussion is directed towards the QGP. First we discuss what it is and how we can detect it. The two last chapters will briefly treat the experiments and the results. It should be mentioned that the experiments are being preformed as this thesis is written. At the moment, one of the more interesting things discovered is that the QGP behaves like a fluid, and not like a gas as predicted.