Zobrazeno 1 - 10
of 1 213
pro vyhledávání: '"Kwong Kwok"'
Autor:
Kwong, Kwok-Kun, Wang, Xianfeng
We investigate integral conditions involving the mean curvature vector $\vec{H}$ or mixed higher-order mean curvatures, to determine when a codimension-two submanifold $\Sigma$ lies on a shear-free (umbilical) null hypersurface in a spacetime. We gen
Externí odkaz:
http://arxiv.org/abs/2307.09287
Autor:
Kwong, Kwok-Kun, Wei, Yong
Publikováno v:
Advances in Mathematics, Vol. 430, 1 Oct 2023, article no. 109213
In this paper, we establish two families of sharp geometric inequalities for closed hypersurfaces in space forms or other warped product manifolds. Both families of inequalities compare three distinct geometric quantities. The first family concerns t
Externí odkaz:
http://arxiv.org/abs/2303.00930
Autor:
Samuel E. Pate, Bin Wang, Yang Zhang, Bing Shen, Enke Liu, Ivar Martin, J. Samuel Jiang, Xiuquan Zhou, Duck Young Chung, Mercouri G. Kanatzidis, Ulrich Welp, Wai‐Kwong Kwok, Zhi‐Li Xiao
Publikováno v:
Advanced Science, Vol 11, Iss 43, Pp n/a-n/a (2024)
Abstract Emerging from the intricate interplay of topology and magnetism, the giant anomalous Hall effect (AHE) is the most known topological property of the recently discovered kagomé ferromagnetic Weyl semimetal Co3Sn2S2 with the magnetic Co atoms
Externí odkaz:
https://doaj.org/article/3fb3cb9a8f3446ee83c581f2f58764e9
Autor:
Kwong, Kwok-Kun
We investigate the effect of the average scalar curvature on the conjugate radius, average area of the geodesic spheres, average volume of the metric balls and the total volume of a closed Riemannian manifold $N$ (or more generally $N$ with finite vo
Externí odkaz:
http://arxiv.org/abs/2209.00237
In a recent work of Brendle-Hirsch-Johne, a notion of intermediate curvature was introduced to extend the classical non-existence theorem of positive scalar curvature on torus to product manifolds. In this work, we study the rigidity when the interme
Externí odkaz:
http://arxiv.org/abs/2208.12240
Autor:
Kwong, Kwok-Kun
By refining the volume estimate of Heintze and Karcher \cite{HK}, we obtain a sharp pinching estimate for the genus of a surface in $\mathbb S^{3}$, which involves an integral of the norm of its traceless second fundamental form. More specifically, w
Externí odkaz:
http://arxiv.org/abs/2206.13791
Autor:
Kwong, Kwok-Kun, Lee, Hojoo
We present an elementary criterion to show the length-minimizing property of geodesics for a large class of conformal metrics. In particular, we prove the length-minimizing property of level curves of harmonic functions and the length-minimizing prop
Externí odkaz:
http://arxiv.org/abs/2202.00942
Autor:
Chun Wai Ng, Kwong-Kwok Wong
Publikováno v:
Scientific Reports, Vol 13, Iss 1, Pp 1-7 (2023)
Abstract Estrogen receptor (ER) positivity by immunohistochemistry has long been a main selection criterium for breast cancer patients to be treated with endocrine therapy. However, ER positivity might not directly correlate with activated ER signali
Externí odkaz:
https://doaj.org/article/09eacd0448934899945a4560e9f5e124
Autor:
Kwong, Kwok-Kun
We provide a simple unified approach to obtain (i) Discrete polygonal isoperimetric type inequalities of arbitrary high order. (ii) Arbitrary high order isoperimetric type inequalities for smooth curves, where both upper and lower bounds for the isop
Externí odkaz:
http://arxiv.org/abs/2111.13352
Autor:
Kwong, Kwok-Kun
We observe some higher order Poincare-type inequalities on a closed manifold, which is inspired by Hurwitz's proof of the Wirtinger's inequality using Fourier theory. We then give some geometric implication of these inequalities by applying them on t
Externí odkaz:
http://arxiv.org/abs/2103.10627