geodesicCOMMENTED.nb

Constructing a space from the geodesic equations Given a space with a metric tensor defined on it, it is easy to write down the system of geodesic equations on it by using the formula for the Christoffel symbols in terms of the metric coefficients. In this paper the inverse problem, of reconstructing the space from the geodesic equations is addressed. A procedure is developed for obtaining the metric tensor explicitly from the Christoffel symbols. The procedure is extended for determining if a second order quadratically semi-linear system can be expressed as a system of geodesic equations, provided it has terms only quadratic in the first derivative apart from the second derivative term. A computer code has been developed for dealing with large systems of geodesic equations.