  Hot dense helium is studied with first-principles computer simulations. By
combining path integral Monte Carlo and density functional molecular dynamics,
a large temperature and density interval ranging from 1000 to 1000000 K and 0.4
to 5.4 g/cc becomes accessible to first-principles simulations and the changes
in the structure of dense hot fluids can be investigated. The focus of this
article are pair correlation functions between nuclei, between electrons, and
between electrons and nuclei. The density and temperature dependence of these
correlation functions is analyzed in order to describe the structure of the
dense fluid helium at extreme conditions.
