On string constructions of pentaquarks

I will discuss the quark system containing of two heavy and three light quarks. In this case the Born-Oppenheimer approximation is appropriate that allows one to consider the energy of the system as a function of a heavy quark separation. I focus on the two low-lying B-O potentials. Even in this case the physics is very rich and complicated. String interactions include: reconnection, breaking, and junction annihilation. I also briefly discuss some possible applications to hadron spectroscopy.