Homogeneous surfaces in the equiaffine space R⁴
The concept of homogeneity, which picks out sprays from the general run of systems of second-order ordinary differential equations in the geometrical theory of such equations, is generalized so as to apply to equations of higher order. Certain properties of the geometric concomitants of a spray are shown to continue to hold for higher-order systems. Third-order equations play a special role, because a strong form of homogeneity may apply to them. The key example of a single third-order equation...
The gradient flow of bending energy for plane curve is studied. The flow is considered under two kinds of constraints; one is under the area and total-length constraints; the other is under the area and local-length constraints. The fundamental results (the local existence and uniqueness) were obtained independently by Kurihara and the second author for the former one; by Okabe for the later one. For the former one the global existence was shown for any smooth initial curves, but the asymptotic...
We study affine hypersurface immersions , where M is an almost complex n-dimensional manifold. The main purpose is to give a condition for (M,J) to be a special Kähler manifold with respect to the Levi-Civita connection of an affine fundamental form.
We give some optimal estimates of the height, curvature and volume of compact hypersurfaces in with constant curvature bounding a planar closed (n-1)-submanifold.
In this paper, we study -dimensional complete connected and oriented space-like hypersurfaces in an (n+1)-dimensional Lorentzian space form with non-zero constant -th mean curvature and two distinct principal curvatures and . We give some characterizations of Riemannian product and show that the Riemannian product is the only complete connected and oriented space-like hypersurface in with constant -th mean curvature and two distinct principal curvatures, if the multiplicities of...
Given a domain of and a -dimensional non-degenerate minimal submanifold of with , we prove the existence of a family of embedded constant mean curvature hypersurfaces in which as their mean curvature tends to infinity concentrate along and intersecting perpendicularly along their boundaries.