Temporal paradox

A temporal, time, or time-travel paradox is a logical contradiction or paradox that appears to be inherent in at least one of the theoretical scenarios suggested by the supposition that "time travel" into the past is possible. These include at hypothetical or fictional forms of backward causation mediated by "time travel" from one time to a time in its past:

• the causal loop, also called a bootstrap paradox, ontological paradox, or predestination paradox, where an event influences the past and causes itself to occur, or where an object originates through time travel, only to be sent later to the time when it originated, thus having no discernible independent origin.
• the grandfather paradox, where an event, that presupposes a specific earlier event, prevents it, by its (backward) influence on the earlier event

See also

• Cosmic censorship hypothesis
• Retrocausality
• Time loop
• Wormhole