More on Long String Dynamics in Gravity on AdS3: Spinning Strings and Rotating BTZ

In this paper we study the classical dynamics of long strings in AdS3, generalizing our previous study, arXiv:1410.3424 [hep-th], to rotating strings and BTZ black holes. As in the non-rotating case, BTZ black holes are generated in the large tension limit, in which string back-reaction must be taken into account. When back-reaction is properly accounted for, collapsing heavy, physical, rotating strings do not generate naked singularities but only BTZ black holes, including extremal ones. The rotating string must contain world-sheet excitations in order to have consistent equations of motion; we describe such additional degrees of freedom implicitly in terms of an effective equation of state.