title : "The Heegaard splittings of surface sums".

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Ruifeng Qiu, East China Normal University

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Abstract: Let $M$ be a compact orientable 3-manifold, and $F$ be an
incompressible surface which cuts $M$ into two components $M_{1}$
and $M_{2}$. In this case, $M$ is called the surface sum of $M_{1}$
and $M_{2}$ along $F$. In this talk, recent improvements on the
Heegaard splittings of surface sums will be introduced.