arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1111.6260math.DGmath.AP
收藏

关于黎曼叶理的一个共形积分不变量

A conformal integral invariant on Riemannian foliations

Guofang Wang, Yongbing Zhang

摘要:

设$M$是一个闭流形,它有一个余维为$q\geq 2$的叶状结构$\mathcal{F}$和一个类三角形度量$g_0$ .令$[g_0]_B$是类似于矩阵的度量的空间,其仅在水平方向上与$g_0$相差正基函数的倍数。假设$Y$是横截共形向量场,并且$(M,\mathcal{F},g_0)$的叶的平均曲率为零。我们表明,积分$\int_MY(R^T_{g^T})dμ_g$是独立的选择$g\in [g_0]_B$,其中$g^T$是横向度规引起的$g$和$R^T$是横向标量曲率。此外,如果$q\geq 3$,我们有任何$g\in [g_0]_B$的$\int_MY(R^T_{g^T})dμ_g=0$。但存在余维2极小黎曼叶理$(M,\mathcal{F},g)$和横截共形向量场$Y$使得$\int_MY(R^T_{g^T})dμ_g\neq 0$ .因此,它是一个非平凡的障碍横Yamabe问题上的最小黎曼叶理的余维2。

英文摘要:

Let $M$ be a closed manifold which admits a foliation structure $\mathcal{F}$ of codimension $q\geq 2$ and a bundle-like metric $g_0$. Let $[g_0]_B$ be the space of bundle-like metrics which differ from $g_0$ only along the horizontal directions by a multiple of a positive basic function. Assume $Y$ is a transverse conformal vector field and the mean curvature of the leaves of $(M,\mathcal{F},g_0)$ vanishes. We show that the integral $\int_MY(R^T_{g^T})dμ_g$ is independent of the choice of $g\in [g_0]_B$, where $g^T$ is the transverse metric induced by $g$ and $R^T$ is the transverse scalar curvature. Moreover if $q\geq 3$, we have $\int_MY(R^T_{g^T})dμ_g=0$ for any $g\in [g_0]_B$. However there exist codimension 2 minimal Riemannian foliations $(M,\mathcal{F},g)$ and transverse conformal vector fields $Y$ such that $\int_MY(R^T_{g^T})dμ_g\neq 0$. Therefore, it is a nontrivial obstruction for the transverse Yamabe problem on minimal Riemannian foliation of codimension 2.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑