Causal vector
= Causal vector
A nonzero <causal vector> is timelike or null: $g(v,v)\le0$ with <metric signature> $(-,+,+,+)$. The zero vector is commonly included when stating the <dominant energy condition>.
= Causal vector
A nonzero <causal vector> is timelike or null: $g(v,v)\le0$ with <metric signature> $(-,+,+,+)$. The zero vector is commonly included when stating the <dominant energy condition>.