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There may actually also be a quark-gluon plasma in the center of neutron stars, but it would be in a very different regime from RHIC - it is ``cold" instead of ``hot". You can kind of think of a Neutron star as a really big nucleus. Actually, Neutron stars are pretty old, but there are always more interesting things happening in that field.
The other "modern" application of nuclear physics is Neutron Stars. The experiments found that this soup has a number of interesting properties, including a remarkably small visoscity. The interactions in this soup are sufficiently strong that it equilibrates, and you get a state of matter known as a "quark-gluon plasma." This is supposed to be the state of matter in the early universe. When the nuclei pass through one another, they produce this really hot region of space, in which you start "pair-producing" a soup of quarks and anti-quarks. It takes massive gold nuclei and smushes them against each-other. The first is the Relativistic Heavy Ion Collider in Brookhaven. There are a few modern and exciting things going on right now in the study of nuclei. For our course this is perfect: we are experts at the wonky stuff. This means there is a bunch of wonky semi-empirical and arm waving stuff. Big time lattice QCD calculations can explain the properties of the neutron - can't do much bigger. It is essentially zero if the nucleons are more than about 10 15 m apart, which roughly corresponds to the size of a nucleus. This is a very strong, but very shortrange, force. Its not that all the nuclear physics problems are solved - the real difficulty is that there is no really good way to quantitatively understand nuclei. Binding Energy and Nuclear Forces The force that binds the nucleons together is called the strong nuclear force. There are not a lot of physicists at Cornell studying them. Nuclei are a bit old school (the 50's were a hot time in nuclear physics). I however chose something you probably haven't heard anything about: nuclei. Today we will cap off the course with some modeling.
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