Interactions of multi-quark states in the chromodielectric model
  We investigate 4-quark ($qq\bar{q}\bar{q}$) systems as well as multi-quark states with a large number of quarks and anti-quarks using the chromodielectric model. In the former type of systems the flux distribution and the corresponding energy of such systems for planar and non-planar geometries are studied. From the comparison to the case of two independent $q\bar{q}$-strings we deduce the interaction potential between two strings. We find an attraction between strings and a characteristic string flip if there are two degenerate string combinations between the four particles. The interaction shows no strong Van-der-Waals forces and the long range behavior of the potential is well described by a Yukawa potential, which might be confirmed in future lattice calculations. The multi-quark states develop an inhomogeneous porous structure even for particle densities large compared to nuclear matter constituent quark densities. We present first results of the dependence of the system on the particle density pointing towards a percolation type of transition from a hadronic matter phase to a quark matter phase. The critical energy density is found at $\epsilon_c = 1.2 GeV/fm^3$. 
Gunnar Martens (1), Carsten Greiner (1), Stefan Leupold (2), Ulrich   Mosel (2) ((1) University of Frankfurt, (2) University...