activity
20102025
most citedIsometric deformations of wave fronts at non-degenerate singular points

10 citations · 45 across the 27 of their papers we have counts for

collaborators

29 papers

math.DG2025

Isometric deformations of pillow boxes

Atsufumi Honda, Miyuki Koiso

Pillow boxes are surfaces used for gift boxes, packaging, and even architectural applications. By definition, a pillow box is isometric to a double rectangle consisting of two copi…

math.DG2024

Mannheim-d'Ocagne-Koenderink type formulas for asymptotic directions

Toshizumi Fukui, Atsufumi Honda, Masaaki Umehara

We consider a surface embedded in the Euclidean 3-space and fix a tangential vector at a given point on the surface. In this paper, we first review a history of the formula…

math.DG2022

Null hypersurfaces as wave fronts in Lorentz-Minkowski space

Shintaro Akamine, Atsufumi Honda, Masaaki Umehara +1

In this paper, we show that ``-complete null hypersurfaces'' (i.e. ruled hypersurfaces foliated by entirety of light-like lines) as wave fronts in the -dimensional Lorent…

math.DG2021

Symmetries of cross caps

Atsufumi Honda, Kosuke Naokawa, Kentaro Saji +2

It is well-known that cross caps on surfaces in the Euclidean 3-space can be expressed in Bruce-West's normal form, which is a special local coordinate system centered at the singu…

math.DG2021

A generalization of Zakalyukin's lemma, and symmetries of surface singularities

Atsufumi Honda, Kosuke Naokawa, Kentaro Saji +2

Zakalyukin's lemma asserts that the coincidence of the images of two wave front germs implies the right equivalence of corresponding map germs under a certain genericity assumption…

math.DG2021★ 1 cited

Singularities of spacelike mean curvature one surfaces in de Sitter space

Atsufumi Honda, Himemi Sato

In this paper, we study the singularities of spacelike constant mean curvature one (CMC 1) surfaces in the de Sitter 3-space. We prove the duality between generalized conelike sing…

math.DG2020

Geometry of lightlike locus on mixed type surfaces in Lorentz-Minkowski 3-space from a contact viewpoint

Atsufumi Honda, Shyuichi Izumiya, Kentaro Saji +1

A surface in the Lorentz-Minkowski -space is generally a mixed type surface, namely, it has the lightlike locus. We study local differential geometric properties of such a locus…

math.DG2020★ 1 cited

Heinz-type mean curvature estimates in Lorentz-Minkowski space

Atsufumi Honda, Yu Kawakami, Miyuki Koiso +1

We provide a unified description of Heinz-type mean curvature estimates under an assumption on the gradient bound for space-like graphs and time-like graphs in the Lorentz-Minkowsk…

math.DG2019★ 4 cited

On the existence of four or more curved foldings with common creases and crease patterns

Atsufumi Honda, Kosuke Naokawa, Kentaro Saji +2

Consider an oriented curve in a domain in the plane . Thinking of as a piece of paper, one can make a curved folding in the Euclidean space $\boldsymbo…

math.DG2019★ 3 cited

Null hypersurfaces in Lorentzian manifolds with the null energy condition

Shintaro Akamine, Atsufumi Honda, Masaaki Umehara +1

Let be a light-like geodesically complete Lorentzian -manifold satisfying the null energy condition. We show that null hypersurfaces properly immersed in $M^{n+1…

math.DG2019★ 1 cited

Curved foldings with common creases and crease patterns

Atsufumi Honda, Kosuke Naokawa, Kentaro Saji +2

Consider a curve in a domain in the plane . Thinking of as a piece of paper, one can make a curved folding in the Euclidean space …

math.DG2019★ 2 cited

Isometric deformations of mixed type surfaces in Lorentz-Minkowski space

Atsufumi Honda

A connected regular surface in Lorentz-Minkowski 3-space is called a mixed type surface if the spacelike, timelike and lightlike point sets are all non-empty. Lightlike points on m…

math.DG2019★ 1 cited

Cuspidal edges with the same first fundamental forms along a knot

Atsufumi Honda, Kosuke Naokawa, Kentaro Saji +2

Letting be a compact -curve embedded in ( means real analyticity), we consider a -cuspidal edge along . When is non-closed, in the a…

math.DG2019★ 3 cited

Bernstein-type theorem for zero mean curvature hypersurfaces without time-like points in Lorentz-Minkowski space

Shintaro Akamine, Atsufumi Honda, Masaaki Umehara +1

Calabi and Cheng-Yau's Bernstein-type theorem asserts that an entire zero mean curvature graph in Lorentz-Minkowski -space which admits only space-li…

math.DG2019★ 1 cited

Duality on generalized cuspidal edges preserving singular set images and first fundamental forms

Atsufumi Honda, Kosuke Naokawa, Kentaro Saji +2

In the second, fourth and fifth authors' previous work, a duality on generic real analytic cuspidal edges in the Euclidean 3-space preserving their singular set i…

math.DG2019★ 2 cited

Behavior of torsion functions of spacelike curves in Lorentz-Minkowski space

Atsufumi Honda

In this paper, we introduce the pseudo-torsion functions along spacelike curves whose curvature vector field has isolated lightlike points in Lorentz-Minkowski 3-space, and prove t…

math.DG2018

Mixed type surfaces with bounded Gaussian curvature in three-dimensional Lorentzian manifolds

Atsufumi Honda, Kentaro Saji, Keisuke Teramoto

A mixed type surface is a connected regular surface in a Lorentzian 3-manifold with non-empty spacelike and timelike point sets. The induced metric of a mixed type surface is a sig…

math.DG2017★ 5 cited

Geometric invariants of -cuspidal edges

Atsufumi Honda, Kentaro Saji

We introduce two invariants called the secondary cuspidal curvature and the bias on -cuspidal edges, and investigate their basic properties. While the secondary cuspidal curva…

math.DG2017★ 10 cited

Isometric deformations of wave fronts at non-degenerate singular points

Atsufumi Honda, Kosuke Naokawa, Masaaki Umehara +1

Cuspidal edges and swallowtails are typical non-degenerate singular points on wave fronts in the Euclidean -space. Their first fundamental forms belong to a class of positive se…

math.DG2017

Complete flat fronts as hypersurfaces in Euclidean space

Atsufumi Honda

By Hartman--Nirenberg's theorem, any complete flat hypersurface in Euclidean space must be a cylinder over a plane curve. However, if we admit some singularities, there are many no…

math.DG2016

Minimal Darboux transformations

U. Hertrich-Jeromin, A. Honda

We derive a permutability theorem for the Christoffel, Goursat and Darboux transformations of isothermic surfaces. As a consequence we obtain a simple proof of a relation between D…

math.DG2016★ 3 cited

Isometric realization of cross caps as formal power series and its applications

Atsufumi Honda, Kosuke Naokawa, Masaaki Umehara +1

Two cross caps in Euclidean -space are said to be formally isometric if their Taylor expansions of the first fundamental forms coincide by taking a suitable local coordinate sys…

math.DG2015★ 3 cited

Fold singularities on spacelike CMC surfaces in Lorentz-Minkowski space

Atsufumi Honda, Miyuki Koiso, Kentaro Saji

Fold singular points play important roles in the theory of maximal surfaces. For example, if a maximal surface admits fold singular points, it can be extended to a timelike minimal…

math.DG2015★ 2 cited

Isometric immersions with singularities between space forms of the same positive curvature

Atsufumi Honda

In this paper, we give a definition of coherent tangent bundles of space form type, which is a generalized notion of space forms. Then, we classify their realizations in the sphere…