The dancing metric, ${G}_2$-symmetry and projective rolling

Affine and projective tree metric theorems

The tree metric theorem provides a combinatorial four point condition that characterizes dissimilarity maps derived from pairwise compatible split systems. A related weaker four point condition characterizes dissimilarity maps derived from circular split systems known as Kalmanson metrics. The tree metric theorem was first discovered in the context of phylogenetics and forms the basis of many t...

Recognition of Plane Projective Symmetry

A novel approach to grouping symmetrical planar curves under a projective transform is described. Symmetric curves are important as a generic model for object recognition where an object class is defined by the set of symmetries that any object in the class obeys. In this paper, a new algorithm is presented for grouping curves based on their correspondence under a plane projectivity. The corres...

Generalized Quadrangles and Projective Axes of Symmetry

We investigate generalized quadrangles Γ that admit at least two projective axes of symmetry. We show that if there are three such axes incident with a common point x, then x is a translation point of Γ. In case that Γ is moreover a compact connected quadrangle with topological parameters (p, p), p ∈ N, then Γ is a topological translation generalized quadrangle. We further investigate the case ...

The Projective Quarter Symmetric Metric Connections and Their Curvature Tensors

Finsler Structures for the Part Metric and Hilbert's Projective Metric and Applications to Ordinary Differential Equations

0. Introduction. Over the past thirty years, a powerful theory of monotone dynamical systems has been developed by many authors. A partial list of contributors would include N. Alikakos, E. N. Dancer, M. Hirsch, P. Hess, M.A. Krasnoselskii, U. Krause, H. Matano, P. Polacik, H.L. Smith, P. Takac and H. Thieme. If one understands the subject more generally as a chapter in the study of linear and ...