arXiv research

We give a spinorial characterization of isometrically immersed surfaces of arbitrary signature into 3-dimensional pseudo-Riemannian space forms. For Lorentzian surfaces, this generalizes a recent work of the first author in $\mathbb{R}^{2,1}$ to other Lorentzian space forms. We also characterize immersions of Riemannia…

We prove that an isometric immersion of a timelike surface in four-dimensional Minkowski space is equivalent to a normalized spinor field which is a solution of a Dirac equation on the surface. Using the quaternions and the complex numbers, we obtain a spinor representation formula that relates the spinor field and the…

Rigidity results for hypersurfaces in warped spacetimes.

The paper studies quasi-umbilical timelike surfaces in a specific geometric setting.

We study manifolds with split-complex structure and apply some general results to the study of Lorentz surfaces. In particular, we apply our results to timelike minimal immersions. The conformal realization of these surfaces is obtained using a representation based on loop groups. The classical Weierstrass representati…

In this paper, we will give an Enneper-type representation for spacelike and timelike minimal surfaces in the Lorentz-Minkowski space $L^{3}$, using the complex and the paracomplex analysis (respectively). Then, we exhibit various examples of minimal surfaces in $L^{3}$ constructed via the Enneper representation formul…

In this study, we deal with the local structure of curves and surfaces immersed in a pseudo-isotropic space I_{p}^{3} that is a particular Cayley-Klein space. We provide the formulas of curvature, torsion and Frenet trihedron in order for spacelike and timelike curves. The causal character of all admissible surfaces in…

Assuming minimal regularity assumptions on the data, we revisit the classical problem of finding isometric immersions into the Minkowski spacetime for hypersurfaces of a Lorentzian manifold. Our approach encompasses metrics having Sobolev regularity and Riemann curvature defined in the distributional sense, only. It ap…

Study biharmonic conformal immersions into anti-de Sitter space, proving rigidity and local existence.

Study biharmonic conformal immersions into anti-de Sitter space, proving rigidity and local existence.

We prove that if $φ\colon \mathbb{R}^2 \to \mathbb{R}^{1+2}$ is a smooth proper timelike immersion with vanishing mean curvature, then necessarily $φ$ is an embedding, and every compact subset of $φ(\mathbb{R}^2)$ is a smooth graph. It follows that if one evolves any smooth self-intersecting spacelike curve (or any pla…

We study constant mean curvature spacelike hypersurfaces and in particular maximal hypersurfaces immersed in pp-wave spacetimes satisfying the timelike convergence condition. We prove the non-existence of compact spacelike hypersurfaces whose constant mean curvature is non-zero and also that every compact maximal hyper…

For a compact spacelike constant mean curvature surface with nonempty boundary in the three-dimensional Lorentz-Minkowski space, we introduce a rotation index of the lines of curvature at the boundary umbilic point, which was developed by Choe \cite{Choe}. Using the concept of the rotation index at the interior and bou…

Study of timelike surfaces in Minkowski space with specific geometric properties.

In this paper, using the classifications of timelike and spacelike ruled surfaces, we study the Mannheim offsets of timelike ruled surfaces in Minkowski 3-space. Firstly, we define the Mannheim offsets of a timelike ruled surface by considering the Lorentzian casual character of the offset surface. We obtain that the M…

Paper classifies timelike Bonnet surfaces in Lorentzian 3-manifolds.

In this paper, we introduce the dual geodesic trihedron (dual Darboux frame) of a timelike ruled surface. By the aid of the E. Study Mapping, we consider timelike ruled surfaces as dual hyperbolic spherical curves and define the Mannheim offsets of timelike ruled surfaces by means of dual Darboux frame. We obtain the r…

The study proves timelike Ricci bounds for low regularity spacetimes using optimal transport.

Timelike curvature and Brunn-Minkowski inequality linked in non-smooth spacetimes.

This study examines geometric properties and offsets of slant timelike-ruled surfaces.

The study classifies timelike meridian surfaces in Minkowski 4-space.

The paper studies timelike loxodromes on specific Lorentzian helicoidal surfaces.

Paper proves timelike minimal surfaces with any number of ends exist.

Timelike geometry of spherical simplices is shown to be isometric to vector spaces.

Timelike Thomsen surfaces are timelike minimal surfaces that are also affine minimal. In this paper, we make use of both the Lorentz conformal coordinates and the null coordinates, and their respective representation theorems of timelike minimal surfaces, to obtain a complete global classification of these surfaces and…

The paper proves properties of Lipschitz spacetimes with bounded Ricci curvature.

Timelike curves in Lorentzian length spaces have a total curvature notion that agrees with smooth curves.

New method finds closed timelike geodesics on Lorentzian manifolds.

We introduce a new approach to the study of timelike minimal surfaces in the Lorentz-Minkowski space through a split-complex representation formula for this kind of surface. As applications, we solve the Björling problem for timelike surfaces and obtain interesting examples and related results. Using the Björling repre…

Study timelike meridian surfaces in Minkowski 4-space with specific properties.

Study timelike minimal surfaces in Heisenberg group using harmonic maps.

Study minimal timelike surfaces in 3D Lorentz-Minkowski space using holomorphic functions.

Defines timelike ideal boundary for non-positively curved Lorentzian spaces.

Constructs Lorentzian harmonic maps and associated timelike surfaces.

Paper studies singularities of timelike minimal surfaces in Minkowski 3-space.

In this paper, it is proved that, no special timelike Frenet curve is a Bertrand curve in $\mathbb{E}_2^4$ and also, in $\mathbb{E}_ν^{n+1}$ $({n \ge 3})$, such that the notion of Bertrand curve is definite only in $\mathbb{E}_1^2$ and $\mathbb{E}_1^3$. Therefore, a generalization of timelike Bertrand curve is defined…

Synthetic splitting theorem for Lorentzian spaces with non-negative curvature.

New parametrizations for minimal timelike surfaces discovered.

Isophote comprises a locus of the surface points whose normal vectors make a constant angle with a fixed vector. In this paper, isophote curves are studied on timelike surfaces in Minkowski 3-space E31. The axises of spacelike and timelike isophote curves are found via their Darboux frames. Subsequently, the relationsh…

In this paper, we investigate timelike slant helix in $S_{1}^{2}$ and we obtain parametric equation of timelike slant helix in $S_{1}^{2}$. Also related examples and their illustrations are given.

The study introduces hyperbolic angles in Lorentzian spaces and characterizes curvature bounds.

The aim of this paper is to present a new perspective on the generation of developable trajectory ruled surfaces in Minkowski 3-space. Involute trajectory ruled surfaces generated by the Frenet trihedron, moving along spacelike involutes of a given timelike space curve, is stated according to Lorentzian timelike angle …

Using techniques of integrable systems, we study a Weierstrass representation formula for timelike surfaces with prescribed mean curvature in Minkowski 3-space. It is shown that timelike minimal surfaces are obtained by integrating a pair of Lorentz holomorphic and Lorentz antiholomorphic null curves in Minkowski 3-spa…

New proof of timelike minimal surfaces using split-harmonic maps.

It is shown that timelike surfaces of constant mean curvature 1 in anti-de Sitter 3-space can be constructed from a pair of Lorentz holomorphic and Lorentz antiholomorphic null curves in PSL(2,R) via Bryant type representation formulae. These formulae are used to investigate an explicit one-to-one correspondence, the s…

No closed timelike geodesics in Kerr spacetimes, proving absence of closed causal geodesics.

We show that to every maximal surface with conelike singularities in Lorentz-Minkowski space $\mathbb{L}^3$ that can be locally represented as the graph of a smooth function, there exists a corresponding timelike minimal surface in $\mathbb{L}^3$. There exists a linear transformation between such a maximal surface and …

The paper proves uniqueness of closed timelike geodesics on de-Sitter tori with one singularity.