grandfather paradox
Causal loop impossibility
The grandfather paradox is a thought experiment in time travel theory that illustrates the logical contradictions of traveling to the past.
If you went back in time and killed your grandfather before he had children, you would never be born—but then you couldn't have traveled back to kill him.
The paradox highlights the impossibility or incoherence of changing events that are conditions for your own existence, and it appears frequently in science fiction exploring temporal mechanics.
Device enabling temporal journeys
- wormholeHypothetical spacetime tunnel
- timelineOrdered display of events
- DeLoreanStainless steel automobile
- flux capacitorFictional temporal displacement device
TARDIS · time dilation · going back · alternate history · quantum leap · time slip · Back to the Future · The Terminator
Autonomous choice capacity
- determinismDoctrine of causal necessity
- fatalismDoctrine of inevitable outcomes
- counterfactualContrary-to-fact supposition
- thought experimentHypothetical scenario for reasoning
metaphysics · identity · personal identity · existence · nonexistence · self-annihilation · hypothetical · logical consistency
Self-causing temporal cycle
- predestinationDivinely predetermined fate
- self-consistencyFreedom from internal contradiction
- causationProduction of effects
- causal chainEvents triggering subsequent events
determinism · consequence · antecedent · trigger · fixed point
Opposing claims, incompatible together
- impossibilityState of being unachievable
- self-contradictionClaim negating itself
- antinomyContradiction between valid conclusions
- logical fallacyError in reasoning
inconsistency · absurdity · conundrum · puzzle · dilemma · catch-22 · self-refuting · vicious circle
Hypothetical coexisting separate reality
- branching timelineParallel diverging event sequences
- alternate realityHypothetical different version of existence
- timeline splitWhere histories diverge
- quantum superpositionCoexisting states before observation
time machine
Device enabling temporal journeys
- wormholeHypothetical spacetime tunnel
- timelineOrdered display of events
- DeLoreanStainless steel automobile
TARDIS · flux capacitor · time dilation · going back · alternate history · quantum leap · time slip · Back to the Future · The Terminator
free will
Autonomous choice capacity
- determinismDoctrine of causal necessity
- fatalismDoctrine of inevitable outcomes
- counterfactualContrary-to-fact supposition
thought experiment · metaphysics · identity · personal identity · existence · nonexistence · self-annihilation · hypothetical · logical consistency · philosophical puzzle
causal loop
Self-causing temporal cycle
- predestinationDivinely predetermined fate
- self-consistencyFreedom from internal contradiction
- causationProduction of effects
causal chain · determinism · consequence · antecedent · trigger · fixed point
contradiction
Opposing claims, incompatible together
- impossibilityState of being unachievable
- self-contradictionClaim negating itself
- antinomyContradiction between valid conclusions
logical fallacy · inconsistency · absurdity · conundrum · puzzle · dilemma · catch-22 · self-refuting · vicious circle · infinite regress
parallel universe
Hypothetical coexisting separate reality
- branching timelineParallel diverging event sequences
- alternate realityHypothetical different version of existence
- timeline splitWhere histories diverge
- Famous Problemstraveling salesman, Monty Hall, prisoner's dilemma, trolley problem, continuum hypothesis
- paradoxescatch-22, causal loop, self-contradiction, ship of Theseus, infinite regress
- time traveltime machine, time loop, time jump, time slip, causal loop
- timesecond, minute, hour, day, seconds
- cosmic mysteriesdark matter, dark energy, black holes, Big Bang, cosmic inflation
- time travel literaturetime loops, time machines, time slip, time police
paradox, grandfather, grandfathers, forefather, forefathers, paradoxical, paradoxes, grandfathered, paradoxically