Explicit Hamiltonian Classification in the $F_4(0)$ Toric Degeneration of $CP^2$

Abstract

We give an explicit coordinate description of the Hamiltonian isotopy classes of the regular Lagrangian torus fibers of the smoothing \(\widehat{F}_4(0)\) of the \(F_4(0)\) toric degeneration, expressed in the explicit Oakley--Usher coordinates on \(\CP^2(\sqrt2)\). For the wall fibers, they are not Hamiltonian isotopic to standard toric fibers, and no two distinct wall fibers are Hamiltonian isotopic. For the off-wall fibers, we find the standard toric fibers they are Hamiltonian isotopic to.