Research
On-device research index

arXiv research

A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

168,695 papers · 148 categories

Trend · papers per month

306191121 · May 202619922001200920172026
48 results for pseudo null curves

The paper studies canal hypersurfaces in Lorentz-Minkowski 4-space.

problem Characterizing canal hypersurfaces formed by pseudo null, partially null, and null curves.
method Obtained parametric expressions and geometric invariants of canal hypersurfaces.
result Characterizations of tubular hypersurfaces in E14E^4_1.

In this paper we deal with curves with degeneration degree two in pseudo-Euclidean spaces of index two. We characterize Bertrand curves. We show a correspondence between the evolute of a null curve and the involute of a certain spacelike curve in the 66-dimensional pseudo-Euclidean space of index two. Also we characte…

2011-06-17abs ↗pdf ↗

We use the isotropic projection of Laguerre geometry in order to establish a correspondence between plane curves and null curves in the Minkowski 33-space. We describe the geometry of null curves (Cartan frame, pseudo-arc parameter, pseudo-torsion, pairs of associated curves) in terms of the curvature of the correspon…

2016-05-06abs ↗pdf ↗

Study null surfaces of pseudo-spherical curves in anti-de Sitter space.

problem Characterize null surfaces of pseudo-spherical spacelike framed curves in anti-de Sitter 3-space.
method Introduced nullcone fronts, classified singularities, defined Anti-de Sitter distance-squared functions.
result Relate singularities of nullcone fronts to those of framed curves.

New parametrizations for minimal timelike surfaces discovered.

problem Finding parametrizations for minimal timelike surfaces in specific spaces.
method Derived representation formulas for null curves leading to parametrizations of minimal timelike surfaces.
result Examples of minimal timelike surfaces constructed.

The study characterizes canal hypersurfaces formed by non-null curves with parallel frame in Minkowski space-time.

problem Characterizing canal hypersurfaces in Minkowski space-time.
method Obtained canal hypersurfaces by pseudo hyperspheres or pseudo hyperbolic hyperspheres with parallel timelike normal vector field.
result Gaussian curvature, mean curvature, and principal curvatures of canal hypersurfaces were derived.

The paper classifies maximal translation surfaces in Lorentz-Minkowski space.

problem Classifying maximal translation surfaces in Lorentz-Minkowski space.
method Analyzing surfaces defined as the sum of two spatial curves, proving properties of generating curves, and classifying surfaces based on curve types.
result A full description of maximal translation surfaces, including new examples not found in Euclidean space.

Study on null helices in semi-Riemannian manifolds with special submanifolds.

problem Investigating geometric properties of null helices on totally umbilical submanifolds in 3D semi-Riemannian manifolds.
method Using the null Frenet frame and degenerate metric condition, equations and invariants characterizing null helices are derived.
result Equations and invariants characterizing null helices on totally umbilical submanifolds in 3D semi-Riemannian manifolds are obtained.

The "dancing metric" is a pseudo-riemannian metric g\pmb{g} of signature (2,2)(2,2) on the space M4M^4 of non-incident point-line pairs in the real projective plane RP2\mathbb{RP}^2. The null-curves of (M4,g)(M^4,\pmb{g}) are given by the "dancing condition": the point is moving towards a point on the line, about which the li…

2015-05-30abs ↗pdf ↗

Study canonical curves and Kropina metrics in Lagrangian contact geometry.

problem Characterize canonical curves and their relationship to Lagrangian contact structures.
method Construct Fefferman-type spaces, analyze chains and null-chains, use Kropina metrics, apply Fermat principle.
result Chains and null-chains in integrable Lagrangian contact structures are geodesics of Kropina metrics.

Conformally quasi-recurrent (CQR)_n pseudo-Riemannian manifolds are investigated, and several new results are obtained. It is shown that the Ricci tensor and the gradient of the fundamental vector are Weyl compatible tensors (the notion was introduced recently by the authors and applies to significative space-times), (…

2013-05-22abs ↗pdf ↗

Study on evolutes and focal surfaces of pseudo-spherical framed immersions in anti-de Sitter space.

problem Investigating singularities of evolutes and focal surfaces of pseudo-spherical framed immersions.
method Introduced pseudo-spherical non-null framed curves, defined moving frames, and analyzed evolutes and focal surfaces.
result Evolutes of pseudo-spherical framed immersions are the sets of singular points of their focal surfaces.

New approach constructs symplectic structure on pseudo-Riemannian geodesics.

problem Dimensional mismatch in classical symplectic structure construction for pseudo-Riemannian geodesics.
method Directly constructs geodesic space as quotient, introduces conformal co-symplectic structure.
result Conformal co-symplectic structure globally describes geometric distribution of geodesics.

Study left-invariant pseudo-Riemannian metrics on Lie groups focusing on null cone Lie algebras.

problem Characterize left-invariant pseudo-Riemannian metrics on Lie groups in the null cone.
method Use bracket flow on Lie algebra to study metrics on Lie groups.
result Classify all cases of null cone Lie algebras in signatures (1,q) and (2,q).

In this study, we define a family of null curves in Minkowski 3-space and called null similar curves. We obtain some properties of these special curves. We show that two null curves are null similar curves if and only if these curves form a null Bertrand pair. Moreover, we obtain that the family of null geodesics and n…

2012-05-10abs ↗pdf ↗

Study null conformal Killing vector fields on complex surfaces.

problem Characterize pseudo-Hermitian surfaces with null vector fields.
method Analyze topological types and use vector fields to define para-hyperhermitian structures.
result Classify compact four-manifolds with orthogonal null Killing vector fields.

Study left-invariant pseudo-Riemannian metrics on Lie groups using moving bracket approach.

problem Characterize left-invariant pseudo-Riemannian metrics on Lie groups with vanishing scalar curvature invariants.
method Using the moving bracket approach, analyze Lie algebras of dimensions ≤ 6 and semi-simple Lie algebras.
result All Lie algebras of dimension ≤ 6 except 3-dimensional solvable Lie algebra are in the null cone, leading to VSI metrics.

The study examines null curves in specific geometric manifolds and their properties.

problem Characterizing null curves in Sasaki-like almost contact B-metric manifolds.
method Expressed Frenet frames and curvatures, proved curvature constancy conditions, and found necessary conditions for generalized helices and null cubic.
result Curvatures of specific null curves are constant if a function on the manifold is constant.

In this study, non-null Frenet-Mannheim curves and non-null Weakened Mannheim curves are investigated in Minkowski 3-space. Some characterizations for this curves are obtained.

2012-04-13abs ↗pdf ↗

In this paper we study null Bertrand curves in R14R_{1}^{4} under the assumption the curve has a Cartan frame. We show that if the derivative vectors of the null Cartan curve in R14R_{1}^{4} is linearly independent, then this curve is not a Bertrand curve. Since then the already known notion of null Bertrand curves in $R…

2011-01-31abs ↗pdf ↗

We describe the geometry of geodesics on a Lorentz ellipsoid: give explicit formulas for the first integrals (pseudo-confocal coordinates), curvature, geodesically equivalent Riemannian metric, the invariant area-forms on the time- and space-like geodesics and invariant 1-form on the space of null geodesics. We prove a…

2007-05-01abs ↗pdf ↗

Proves limit curve theorem for incomplete metric spaces, applies to null distance in Lorentzian manifolds.

problem Control of Lorentzian lengths of limit curves in incomplete metric spaces.
method Proves limit curve theorem for incomplete metric spaces and applies to null distance.
result Strong control on Lorentzian lengths of limit curves in Sormani and Vegas' null distance.

The local motion of a null curve in Minkowski 3-space induces an evolution equation for its Lorentz invariant curvature. Special motions are constructed whose induced evolution equations are the members of the KdV hierarchy. The null curves which move under the KdV flow without changing shape are proven to be the traje…

2009-11-23abs ↗pdf ↗

Proves spectral inequality and null-controllability for elliptic operators on closed manifolds.

problem Proving spectral inequalities and null-controllability for elliptic pseudo-differential operators.
method Periodization approach in time inspired by global pseudo-differential calculus.
result Established spectral inequality and null-controllability for elliptic operators on closed manifolds.

In this paper we will show that a Lagrangian, Lorentzian surface M12M^2_1 in a complex pseudo space form M~12(4c)\widetilde M^2_1 (4c) is pseudo-isotropic if and only if MM is minimal. Next we will obtain a complete classification of all Lagrangian, Lorentzian surfaces which are lightlike pseudo-isotropic but not pseudo-isot…

2016-10-05abs ↗pdf ↗

Study of null φ-slant curves in specific 3D manifolds.

problem Characterizing null φ-slant curves in 3D normal almost contact B-metric manifolds.
method Analyzing the geometric properties and Frenet frames of φ-slant null curves.
result Existence of a unique Frenet frame for non-geodesic φ-slant null curves.

In this paper, we investigate the similarity transformations in the Minkowski-n space. We study the geometric invariants of non-null curves under the similarity transformations. Besides, we extend the fundamental theorem for a non-null curve according to a similarity motion. We determine all non-null self-similar curve…

2014-08-07abs ↗pdf ↗

Paper connects surfaces in 4D and 3D spacetime.

problem Finding relations between Lorentz surfaces in different spacetime dimensions.
method Weierstrass-type representations for null curves and surfaces.
result Relation between minimal Lorentz surfaces in R24\mathbb R^4_2 and R13\mathbb R^3_1.

The paper develops theory for holomorphic null curves in SL2(C).

problem Developing theory for holomorphic null curves in SL2(C).
method Establish Runge, Mergelyan, Mittag-Leffler, and Carleman type theorems for holomorphic null immersions.
result Proves every open Riemann surface admits a proper holomorphic null embedding into SL2(C).

Study null curves and their motion in 3D flat space-time, leading to integrable hierarchies.

problem Understanding null curves and their motion in 3D flat space-time.
method Analyzing the motion of null curves and their surfaces, deriving integrability conditions and hierarchies.
result Obtained one- and two-soliton surfaces associated with the MKdV equation, showing singularities in finite time.

The paper connects hyperbolic spinors to non-null framed curves in Minkowski 3-space.

problem Understanding geometric properties of non-null framed curves.
method Developed new adapted frames for non-null framed curves and investigated their hyperbolic spinor representations.
result Found geometric results and interpretations for non-null framed curves.

In this paper we study the non-geodesic non-null biharmonic curves in 3-dimensional hyperbolic Heisenberg group. We prove that all of the non-geodesic non-null biharmonic curves in 3-dimensional hyperbolic Heisenberg group are helices. Moreover, we obtain explicit parametric equations for non-geodesic non-null biharmon…

2011-03-03abs ↗pdf ↗

We study pseudoholomorphic curves in the nearly Kalher CP3\mathbf{CP}^3. It is shown that a class of curves called null-torsion are in one to one correspondence with the integrals of a holomorphic contact system on the usual Kahler CP3\mathbb{CP}^3 studied by Bryant. Browing Bryant's result we get plenty of such curves. …

2006-05-29abs ↗pdf ↗

Study on null-torsion holomorphic curves in 6-sphere, focusing on their second variation.

problem Characterize the second variation of area for null-torsion holomorphic curves in the round 6-sphere.
method Analyzing the spectrum of the Jacobi operator for compact null-torsion holomorphic curves.
result For g6g \leq 6, the multiplicity of the lowest eigenvalue λ1=2λ_1 = -2 is exactly 4d4d.