Alcuni invarianti di contatto di due varietà in uno spazio proiettivo
Algebraic aspects of web geometry
Algebraic aspects of web geometry, namely its connections with the quasigroup and loop theory, the theory of local differential quasigroups and loops, and the theory of local algebras are discussed.
Algebraic geometry and local differential geometry
Algebraic representation formulas for null curves in Sl(2,ℂ)
We study curves in Sl(2,ℂ) whose tangent vectors have vanishing length with respect to the biinvariant conformal metric induced by the Killing form, so-called null curves. We establish differential invariants of them that resemble infinitesimal arc length, curvature and torsion of ordinary curves in Euclidean 3-space. We discuss various differential-algebraic representation formulas for null curves. One of them, a modification of the Bianchi-Small formula, gives an Sl(2,ℂ)-equivariant bijection...
Algèbres de Clifford dégénérées et revêtements des groupes conformes affines orthogonaux et symplectiques
All Bézier curves are attractors of iterated function systems.
All constant mean curvature tori in R3, S3, H3 in terms of theta-functions.
All linear and bilinear natural concomitants of vector valued differential forms
Almost c-spinorial geometry
Almost c-spinorial geometry arises as an interesting example of the metrisability problem for parabolic geometries. It is a complex analogue of real spinorial geometry. In this paper, we first define the type of parabolic geometry in question, then we discuss its underlying geometry and its homogeneous model. We compute irreducible components of the harmonic curvature and discuss the conditions for regularity. In the second part of the paper, we describe the linearisation of the metrisability problem...
Almost Every Curve in R3 Bounds a Unique Area Minimizing Surface.
An a Priori Estimate for the Oscillation of the Normal to a Hypersurface Whose First and Second Variation With Respect to an Elliptic Integrand is Controlled.
An affine embedding of the gamma manifold.
An algorithm for evolutionary surfaces.
An alternative moving frame for tubular surfaces around time-like curves in the Minkowski 3-space.
An angle metric through the notion of Grassmann representative.
An equality for the curvature function of a simple and closed curve on the plane.
An equichordal characterization of round spheres.
An equivalence theorem for submanifolds of higher codimensions
For a submanifold of of any codimension the notion of type number is introduced. Under the assumption that the type number is greater than 1 an equivalence theorem is proved.
An -system for a revolution surface without boundary.
An Inequality between the Exterior Diameter and the Mean Curvature of Bounded Immersions.