A temporal paradox, time paradox, or time travel paradox is a paradox, an apparent contradiction, or a logical contradiction that is associated with the idea of time and time travel.
What is time? While most people think of time as a constant, physicist Albert Einstein showed that time is an illusion; it is relative — it can vary for different observers depending on your speed through space. To Einstein, time is the "fourth dimension." There is nothing in Einstein’s theories of relativity to rule out time travel, although the very notion of traveling to the past violates one of the most fundamental premises of physics, that of causality.
The Time travel paradoxes basically fall into two broad categories, namely:
🔹Closed Causal Loops: these types involve a self-existing time loop in which cause and effect run in a repeating circle, but is also internally consistent with the timeline’s history, such as the Predestination Paradox and the Bootstrap Paradox
🔹Consistency Paradoxes: these types generate a number of timeline inconsistencies related to the possibility of altering the past, such as the Grandfather Paradox and other similar variants such as The Hitler paradox, and Polchinski’s Paradox.
Scientists eager to avoid the paradoxes presented by time travel have come up with a number of ingenious ways in which to present a more consistent version of reality, including:
🔸The Solution: time travel is impossible because of the very paradox it creates.
🔸Self-healing hypothesis: successfully altering events in the past will set off another set of events which will cause the present to remain the same.
🔸The Multiverse or “many-worlds” hypothesis: an alternate parallel universe or timeline is created each time an event is altered in the past.
🔸Erased timeline hypothesis: a person traveling to the past would exist in the new timeline, but have their own timeline erased.
