Causality and conjugate points in general plane waves
Causality and conjugate points in general plane waves
Let = 0 × 2 be a pp-wave-type spacetime endowed with the metric ⟨·, ·⟩z = ⟨·, ·⟩x + 2du dv + H(x, u) du2, where (0, ⟨·, ·⟩x) is any Riemannian manifold and H(x, u) is an arbitrary function. We show that the behaviour of H(x, u) at spatial …