MathDB
Miklos Schweitzer 1979_6

Source: pseudo-Riemannian metric

January 28, 2009
analytic geometryconicsadvanced fieldsadvanced fields unsolved

Problem Statement

Let us defined a pseudo-Riemannian metric on the set of points of the Euclidean space E3 \mathbb{E}^3 not lying on the z z-axis by the metric tensor \left( \begin{array}{ccc} 1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & \minus{}\sqrt{x^2\plus{}y^2} \\ \end{array} \right), where (x,y,z) (x,y,z) is a Cartesian coordinate system E3 \mathbb{E}^3. Show that the orthogonal projections of the geodesic curves of this Riemannian space onto the (x,y) (x,y)-plane are straight lines or conic sections with focus at the origin P. Nagy