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 2104.06198math.APmath.DG
收藏

光滑奇异曲面上调和函数水平曲线的等周不等式与几何

Isoperimetric inequalities and geometry of level curves of harmonic functions on smooth and singular surfaces

Tomasz Adamowicz, Giona Veronelli

摘要:

研究了曲面上调和函数水平曲线长度的对数凸性及相关的等周型不等式。结果处理光滑的表面,以及与奇异亚历山德罗夫表面(也称为表面有界积分曲率),一类,其中包括例如表面与圆锥奇点和表面的CAT(0)型。此外,我们还研究了具有非必要常高斯曲率$K$的曲面上的水平曲线的测地曲率和调和函数的最速下降。这样的测地曲率函数证明满足某些拉普拉斯型方程和不等式,从这些方程和不等式我们可以推导出各种最大值和最小值原理。补充的结果是一些增长估计的衍生物$L'$和$L''$的长度的水平曲线函数$L$,以及举例说明的演示。我们的工作推广了Alessandrini,Longinetti,Talenti,Ma-Zhang和Wang-Wang的一些结果.

英文摘要:

We investigate the logarithmic convexity of the length of the level curves for harmonic functions on surfaces and related isoperimetric type inequalities. The results deal with smooth surfaces, as well as with singular Alexandrov surfaces (also called surfaces with bounded integral curvature), a class which includes for instance surfaces with conical singularities and surfaces of CAT(0) type. Moreover, we study the geodesic curvature of the level curves and of the steepest descent for harmonic functions on surfaces with non-necessarily constant Gaussian curvature $K$. Such geodesic curvature functions turn out to satisfy certain Laplace-type equations and inequalities, from which we infer various maximum and minimum principles. The results are complemented by a number of growth estimates for the derivatives $L'$ and $L''$ of the length of the level curve function $L$, as well as by examples illustrating the presentation. Our work generalizes some results due to Alessandrini, Longinetti, Talenti, Ma--Zhang and Wang--Wang.

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。

↑