Hitting Topological Minor Models in Planar Graphs is Fixed Parameter Tractable

Abstract: For a finite collection of graphs ${\cal F}$, the \textsc{${\cal F}$-TM-Deletion} problem has as input an $n$-vertex graph $G$ and an integer $k$ and asks whether there exists a set $S \subseteq V(G)$ with $|S| \leq k$ such that $G \setminus S$ does not contain any of the graphs in ${\cal F}$ as a topological minor. We prove that for every such ${\cal F}$, \textsc{${\cal F}$-TM-Deletion} is fixed parameter tractable on planar graphs. Our algorithm runs in a $$2^{{\mathcal{O}(k^2)}\cdot} n<sup>{2}$$ time or, alternatively in $2^{{\mathcal{O}(k)}\cdot} n<sup>{4}$ time. Our techniques can easily be extended to graphs that are embeddable on any fixed surface.