8 citations · 17 across the 5 of their papers we have counts for
5 papers
Two-numbers and Euler characteristics for quandles
Ryoya Kai, Akira Kubo, Hiroshi Tamaru
Quandles can be regarded as generalizations of symmetric spaces. In the theory of symmetric spaces developed by Chen and Nagano, there is an interesting relationship between the tw…
Realizations of some contact metric manifolds as Ricci soliton real hypersurfaces
Jong Taek Cho, Takahiro Hashinaga, Akira Kubo +2
Ricci soliton contact metric manifolds with certain nullity conditions have recently been studied by Ghosh and Sharma. Whereas the gradient case is well-understood, they provided a…
On the moduli spaces of left-invariant pseudo-Riemannian metrics on Lie groups
Akira Kubo, Kensuke Onda, Yuichiro Taketomi +1
In this paper, we formulate a procedure to obtain a generalization of Milnor frames for left-invariant pseudo-Riemannian metrics on a given Lie group. This procedure is an analogue…
Homogeneous Ricci soliton hypersurfaces in the complex hyperbolic spaces
Takahiro Hashinaga, Akira Kubo, Hiroshi Tamaru
A Lie hypersurface in the complex hyperbolic space is an orbit of a cohomogeneity one action without singular orbit. In this paper, we classify Ricci soliton Lie hypersurfaces in t…
A sufficient condition for congruency of orbits of Lie groups and some applications
Akira Kubo, Hiroshi Tamaru
We give a sufficient condition for isometric actions to have the congruency of orbits, that is, all orbits are isometrically congruent to each other. As applications, we give simpl…