Explicit Hamiltonian Classification in the F₄(0) Toric Degeneration of CP²

2026/08/05 by Han Lou, Shuo Zhang
Mathematics · #math.SG #msc:53D12 #msc:53D20

paper · pdf

19 pages, 4 figures, comments welcome!

arxiv created 2026/08/05 · arxiv updated 2026/08/06

Abstract

We give an explicit coordinate description of the Hamiltonian isotopy classes of the regular Lagrangian torus fibers of the smoothing \(\widehatF₄(0)\) of the \(F₄(0)\) toric degeneration, expressed in the explicit Oakley--Usher coordinates on \(\CP²(√2)\). 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.

Citations

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