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arXiv · 2608.28197

Semitoric systems with $2n$ Focus-Focus singularities

Haruhisa Mura
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Abstract

In this paper, we provide new explicit examples of semitoric systems. More precisely, for any natural number $n$, we give a semtioric moment map $F_n$ with $2n$ focus-focus singularities defined on a symplectic manifold $(M_n,\omega_n)$ of diffeomorphism type $\mathbb{CP}^2\sharp(2n+1)\overline{\mathbb{CP}}{}^2$.

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Haruhisa Mura. 2026-08-28. Semitoric systems with $2n$ Focus-Focus singularities. https://arxiv.org/abs/2608.28197

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