arXiv subjects

Masoud Hassani

Publications and source records attributed to Masoud Hassani.

3 recordsLinked to original sources

arXiv2018

Cohomogeneity one conformal actions on the three-dimensional essential Riemannian spaces

The aim of this paper is to classify the cohomogeneity one conformal actions on the three-dimensional essential Riemannian spaces, up to orbit equivalence. Among other results, the representations of all connected Lie groups acting with cohomogeneity one or zero within the full conformal group of a given three-dimensional essential Riemannian space are determined, up to conjugacy, and the orbits are specified up to conformal equivalence.

math.DG↗

arXiv2018

Cohomogeneity one actions on the three-dimensional Einstein universe

The aim of this paper is to classify the cohomogeneity one conformal actions on the 3-dimensional Einstein universe $Ein^{1;2}$ , up to orbit equivalence. In a recent paper [21], we studied the unique (up to conjugacy) irreducible action of $PSL(2; \mathbb{R})$ on $Ein^{1;2}$ and we showed that the action is of cohomogeneity one. In the present paper, we determine all the subgroups of $Conf(Ein^{1;2})$, up to conjugacy, acting reducibly and with cohomogeneity one on $Ein^{1;2}$. We show that any cohomogeneity one reducible action on $Ein^{1;2}$ induces a fixed point in the 4-dimensional projective space $\mathbb{R} \mathbb{P}^4$. Also, we describe all the codimension one induced orbits by these actions

math.DG↗

arXiv2017

On the irreducible action of psl(2, r) on the 3-dimensional einstein universe

We describe the orbits of the irreducible action of PSL(2, R) on the 3-dimensional Einstein universe Ein 1,2. This work completes the study in [2], and is one element of the classification of cohomo-geneity one actions on Ein 1,2 ([5]).

math.DG↗