论文标题
复杂性的一键骨骼 - 一个空间
Toric one-skeletons for complexity-one spaces
论文作者
论文摘要
复杂性 - 一个空间是一个紧凑的符号歧管$(m,ω)$,并具有有效的hamiltonian动作,对圆圈的$ t dimension $ \ frac {1} {2} {2} \ dim(m)-1 $。在本说明中,我们证明,对于一定类别的复杂性 - 一个空间,Chern类$ c_ {n-1} $的poincaré双重双重二重奏可以由$ \ frac {n} {n} {n} {2}χ(m)$ symplectic嵌入式嵌入式$ 2 $ spheres($ 2 $ -spheres)($χ(m)$ um $ ul y y y y y y y y y y y y y y y y y $ m,n $ n y y y y y y y y y y y y y y y y y $ m,我们将这样的集合称为紫色的一键骨骼。复杂性 - 一个空间的分类是符号几何形状中的重要主题。这些空间的一个很好的子类别是单调的。圆环一骨的存在是一种有用的工具,可以理解六维单调复杂性 - 一个空间。特别是,我们将证明存在这样一个空间的感谢您的单骨骼的存在,这意味着第二个Betti的$ M $最多是七个。这是Sabatini-Sepe和Lindsay-Panov的结果简单应用。
A complexity-one space is a compact symplectic manifold $(M, ω)$ endowed with an effective Hamiltonian action of a torus $T$ of dimension $\frac{1}{2}\dim(M)-1$. In this note we prove that for a certain class of complexity-one spaces the Poincaré dual of the Chern class $c_{n-1}$ can be represented by a collection of $\frac{n}{2}χ(M)$ symplectic embedded $2$-spheres, where $χ(M)$ is the Euler characteristic of $M$ and $\dim(M)=2n$. We call such a collection a toric one-skeleton. The classification of complexity-one spaces is an important subject in symplectic geometry. A nice subcategory of those spaces are the ones which are monotone. The existence of a toric one-skeleton is a useful tool to understand six-dimensional monotone complexity-one spaces. In particular, we will show that the existence of a toric one-skeleton for such a space implies that the second Betti number of $M$ is at most seven. This is a simple application of results by Sabatini-Sepe and Lindsay-Panov.