JSJ decompositions of doubles of free groups
arXiv:1611.01424 · doi:10.1017/S0017089519000168
Abstract
We classify all possible JSJ decompositions of doubles of free groups of rank two and we then compute the Makanin-Razborov diagram of a particular double of a free group and deduce that in general limit groups are not freely subgroup separable.
18 pages, added a missing case in the main theorem, multiple small improvements