A Null Geodesic Orbit Space Whose Null Orbits Require a Reparametrization
نویسندگان
چکیده
We exhibit an example of a homogeneous Lorentzian manifold G/H whose homogeneous geodesics form just the light-cone and a hyperplane in the tangent space. For all light-like homogeneous geodesics, the natural parameter of the orbit is not the affine parameter of the geodesic.
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