2 problems

Let $(M,\mathbf{g})$ be a spacetime with time function $\tau$, and let $\mathbf{h}$ be a complete Riemannian metric such that $\tau$ is anti-Lipschitz with respect to $\mathbf{h}$.…

Let $(M,\mathbf{g})$ be a spacetime with time function $\tau$, and let $\hat d_\tau$ denote the induced null distance on $M$. Theorem 3.14 states that if $\tau$ is anti-Lipschitz o…