causality paradox

American  

[kaw-zal-i-tee par-uh-doks] / kɔˈzæl ɪ ti ˌpær ə dɒks /

noun

1. (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.

2. Also called causality violation.  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.

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causality paradox Scientific  

/ kô-zăl′ĭ-tē /

1. A paradox resulting from hypothetical time travel, in which an individual travels back in time and performs actions that would ultimately have made the time travel impossible (as by killing one's parents at a time preceding one's birth).

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Etymology

Origin of causality paradox

First recorded in 1910–15