Remarks on causal decrease, omniscient foliations and null lines in spacetimes

This work provides a counterexample to the previously asserted non--existence of future null lines in strongly causal spacetimes $(M, \mathbf{g})$ foliated by a past--omniscient timelike foliation $\mathcal{F}$ with a compact leaf space $Q$. We introduce a new hypothesis requiring the timelike vecto... View More