Hyperbolic Raisa Orbits of the Second Order in an Extended Hyperbolic Plane

Year 2021, Volume: 14 Issue: 1, 194 - 206, 15.04.2021

Lyudmila N. Romakina

https://doi.org/10.36890/iejg.904467

Abstract

In this paper, we study conics, which are invariant under the hyperbolic inversion with respect to the absolute of an extended hyperbolic plane $H^2$ of curvature radius $\rho$, $\rho \in \mathbb R_+$. They are called the hyperbolic Raisa Orbits of the second order. We prove that each hyperbolic Raisa Orbits of the second order in $H^2$ belongs to one of four conics types of this plane. These types are as follows: the bihyperbolas of one sheet; the hyperbolas; the hyperbolic parabolas of one sheet and two branches; the elliptic cycles of radius $\pi \rho / 4$. The family of all hyperbolic Raisa Orbits from the family of all bihyperbolas of one sheet (or all hyperbolas) defined exactly up to motions, is one-parametric. The family of all hyperbolic Raisa Orbits from the family of all hyperbolic parabolas of one sheet and two branches (or all elliptic cycles) contains a unique conic defined exactly up to motions.

Keywords

Extended hyperbolic plane, hyperbolic plane of positive curvature, hyperbolic plane, Raisa Orbit, $R$-orbit, inversion, absolute

Thanks

Dear Dr. Prof. Kazim ILARSLAN, Please, accept for publication my new manuscript on conics, which are invariant under inversions with respect to the absolute of an extended hyperbolic plane. With best regards, Lyudmila ROMAKINA

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