activity
20112024
most citedRecognizable classification of Lorentzian distance-squared mappings

15 citations · 38 across the 29 of their papers we have counts for

collaborators

30 papers

math.DG2024

A characterization of the Legendre involution on the class of generic frontals

Takashi Nishimura

We show that, under an additional mild assumption, on the class of generic frontals, any involution whose fixed point set is exactly the same as the fixed point set of the Legendre…

math.DG2023

Envelopes of straight line families in the plane

Takashi Nishimura

There is a widespread method to represent the envelope when a given hyperplane family creates an envelope. However, one sometimes encounters cases when the widespread method fails…

math.DG2023

Envelopes created by circle families in the plane

Yongqiao Wang, Takashi Nishimura

In this paper, on envelopes created by circle families in the plane, all four basic problems (existence problem, representation problem, problem on the number of envelopes, problem…

math.GT2021★ 3 cited

Hyperplane families creating envelopes

Takashi Nishimura

A simple geometric mechanism: "the locus of intersections of perpendicular bisectors and normal lines", often arises in many guises in Nonlinear Sciences. In this paper, a new appl…

math.MG2020★ 1 cited

Spherical Separation Theorem

Huhe Han, Takashi Nishimura

In this paper, it is shown that for any two non-empty closed (resp., open) and spherical convex subsets of , the intersection $\mathcal{W}_1\cap…

math.DG2019

Anti-orthotomics of frontals and their applications

Stanisław Janeczko, Takashi Nishimura

Let be a frontal with its Gauss mapping and let be a point such that for any .…