相对Kähler度量空间中的测地线

Remarks on the geodesic-Einstein metrics of a relative ample line bundle (with an appendix by Xu Wang)

In this paper, we introduce the associated geodesic-Einstein flow for a relatively ample line bundle $L$ over the total space $\mathcal{X}$ of a holomorphic fibration and obtain a few properties of that flow. In particular, we prove that the pair $(\mathcal{X}, L)$ is nonlinear semistable if the {associated} Donaldson type functional is bounded from below and the geodesic-Einstein flow has long-time {existence property}. We also define the associated $S$-classes and $C$-classes for $(\mathcal{X}, L)$ and obtain two inequalities between them when $L$ admits a geodesic-Einstein metric. Finally, …

The space of finite-energy metrics over a degeneration of complex manifolds

Given a degeneration of compact projective complex manifolds $X$ over the punctured disc, with meromorphic singularities, and a relatively ample line bundle $L$ on $X$, we study spaces of plurisubharmonic metrics on $L$, with particular focus on (relative) finite-energy conditions. We endow the space $\hat \cE^1(L)$ of relatively maximal, relative finite-energy metrics with a $d_1$-type distance given by the Lelong number at zero of the collection of fibrewise Darvas $d_1$-distances. We show that this metric structure is complete and geodesic. Seeing $X$ and $L$ as schemes $X_\K$, $L_\K$ over …

On Some Properties of Finsler Manifolds of Stretch Curvature

Finsler metrics with relatively non-negative (non-positive, respectively), constant and isotropic stretch curvatures are investigated in this paper. In particular, it is proved that every non-Riemannian $(α, β)$-metric with a nonzero constant flag curvature and a non-zero relatively isotropic stretch curvature over a manifold of dimension $n\geq 3$ is of a characteristic scalar constant over the Finsler geodesics. It is also shown that every compact Finsler manifold with a relatively non-negative (non-positive, respectively) stretch curvature is a Landsberg metric. Finsler manifolds with $2$-d…

关于嵌入曲线空间上的完备黎曼度量

On a Complete Riemannian Metric on the Space of Embedded Curves

本文提出了一种新的完备黎曼度量，用于研究嵌入曲线空间中的测地问题，并展示了该度量在多个方面的完备性及切点能量的光滑性。

Area minimizing surfaces in homotopy classes in metric spaces

We introduce and study a notion of relative 1-homotopy type for Sobolev maps from a surface to a metric space spanning a given collection of Jordan curves. We use this to establish the existence and local Hölder regularity of area minimizing surfaces in a given relative 1-homotopy class in proper geodesic metric spaces admitting a local quadratic isoperimetric inequality. If the underlying space has trivial second homotopy group then relatively 1-homotopic maps are relatively homotopic. We also obtain an analog for closed surfaces in a given 1-homotopy class. Our theorems generalize and streng…

抛物双曲空间中的几何有限性

Geometric finiteness in paracomplex hyperbolic spaces

本文通过抛物双曲空间建立离散子群研究框架，用弱凸包上的作用刻画三类子群，构造Busemann型水平函数，并证明相对阿诺索夫子群的测地流一致双曲。