The nonexistence of a skein theory for the tangle group functor
Let Tang\mathcal{T}angTang be the category of tangles, let ΛGrp\Lambda\mathbf{Grp}ΛGrp be the category of groups, and let Γ :Tang→ΛGrp\Gamma\colon\mathcal{T}ang\to\Lambda\mathbf{Grp}Γ:Tang→ΛGrp be the tangle group…