causality paradox

(in science fiction) the hypothetical contradiction of cause-and-effect in time travel and the potential disruption to a timeline resulting from changes in the past that affect the current reality, as in the grandfather paradox.

Also called cau·sal·i·ty vi·o·la·tion [kaw-, zal, -i-tee vahy-, uh, -ley-sh, uh, n]. Astrophysics. an effect that does not belong to the future light cone of its cause, or an effect occurring before the light cone of its cause, as the exchange of superluminal signals between distant observers who are in a relative motion receding one from another.