A Heegaard splitting is a type of combinatorial structure on an orientable compact 3-manifold.We will give a survey on Heegaard spliting and its applications,including those pertaining to the classification and stabil...A Heegaard splitting is a type of combinatorial structure on an orientable compact 3-manifold.We will give a survey on Heegaard spliting and its applications,including those pertaining to the classification and stabilization problem,reducibilities,minimal Heegaard splitting and Heegaard distance.展开更多
It is Thurston's result that for a hyperbolic knot K in S^3, almost all Dehn fillings on its complement result in hyperbolic 3-manifolds except some exceptional cases. So almost all produced 3-manifolds have the s...It is Thurston's result that for a hyperbolic knot K in S^3, almost all Dehn fillings on its complement result in hyperbolic 3-manifolds except some exceptional cases. So almost all produced 3-manifolds have the same geometry. It is known that its complement in S^3, denoted by E(K), admits a Heegaard splitting. Then it is expected that there is a similar result on Heegaard distance for Dehn fillings. In this paper, Dehn fillings on genus two Heegaard splittings are studied. More precisely, we prove that if the distance of a given genus two Heegaard splitting of E(K) is at least 3, then for any two degenerating slopes on ?E(K), there is a universal bound of their distance in the curve complex of ?E(K).展开更多
Let M be a compact orientable 3-manifold with 0M connected. If V Us W is a Heegaard splitting of M with distance at least 6, then the 0-stabilization of V Us W along OM is unstabilized. Hence M has at least two unstab...Let M be a compact orientable 3-manifold with 0M connected. If V Us W is a Heegaard splitting of M with distance at least 6, then the 0-stabilization of V Us W along OM is unstabilized. Hence M has at least two unstabilized Heegaard splittings with different genera. The basic tool is a result on disk complex given by Masur and Schleimer.展开更多
Let M be a connected orientable compact irreducible 3-manifold. Suppose that αM consists of two homeomorphic surfaces F1 and F2, and both F1 and F2 are compressible in M. Suppose furthermore that g(M, F1) = g(M) + g(...Let M be a connected orientable compact irreducible 3-manifold. Suppose that αM consists of two homeomorphic surfaces F1 and F2, and both F1 and F2 are compressible in M. Suppose furthermore that g(M, F1) = g(M) + g(F1), where g(M, F1)is the Heegaard genus of M relative to F1. Let Mfbe the closed orientable 3-manifold obtained by identifying F1 and F2 using a homeomorphism f : F1 → F2. The authors show that if f is sufficiently complicated, then g(Mf) = g(M, αM) + 1.展开更多
基金This work was partially supported by Science and Technology Commission of Shanghai Municipality(STCSM),(18dz2271000)and NSFC(12131009)。
文摘A Heegaard splitting is a type of combinatorial structure on an orientable compact 3-manifold.We will give a survey on Heegaard spliting and its applications,including those pertaining to the classification and stabilization problem,reducibilities,minimal Heegaard splitting and Heegaard distance.
基金supported by National Natural Science Foundation of China(Grant Nos.11371094,11571110 and 11601065)
文摘It is Thurston's result that for a hyperbolic knot K in S^3, almost all Dehn fillings on its complement result in hyperbolic 3-manifolds except some exceptional cases. So almost all produced 3-manifolds have the same geometry. It is known that its complement in S^3, denoted by E(K), admits a Heegaard splitting. Then it is expected that there is a similar result on Heegaard distance for Dehn fillings. In this paper, Dehn fillings on genus two Heegaard splittings are studied. More precisely, we prove that if the distance of a given genus two Heegaard splitting of E(K) is at least 3, then for any two degenerating slopes on ?E(K), there is a universal bound of their distance in the curve complex of ?E(K).
基金supported by the National Natural Science Foundation of China(Nos.11271058,11171108)
文摘Let M be a compact orientable 3-manifold with 0M connected. If V Us W is a Heegaard splitting of M with distance at least 6, then the 0-stabilization of V Us W along OM is unstabilized. Hence M has at least two unstabilized Heegaard splittings with different genera. The basic tool is a result on disk complex given by Masur and Schleimer.
基金supported by the National Natural Science Foundation of China(No.11271058)The second author is supported by the National Natural Science Foundation of China(No.11171108)
文摘Let M be a connected orientable compact irreducible 3-manifold. Suppose that αM consists of two homeomorphic surfaces F1 and F2, and both F1 and F2 are compressible in M. Suppose furthermore that g(M, F1) = g(M) + g(F1), where g(M, F1)is the Heegaard genus of M relative to F1. Let Mfbe the closed orientable 3-manifold obtained by identifying F1 and F2 using a homeomorphism f : F1 → F2. The authors show that if f is sufficiently complicated, then g(Mf) = g(M, αM) + 1.