The chronology protection

Guess for the protection of the chronology on the journey in time

Mathematically, the possibility of time travel is represented by the existence of the closed curve of type time.

For closed curves of type time, have been suggested many scenarios, but attempts to incorporate quantum effects into general relativity using gravity semiclasica, seem to make plausible that, at the time of transit, the fluctuations in the power vacuum to increase the energy density of a so-called time machine to infinity, thus destroying the time machine at the same instant in which it has been created , or preventing that anyone can use it.

A test of the validity of the chronology protection conjecture would require a definitive theory of quantum gravity.

Only if physicists had a theory of quantum gravity whose predictions were confirmed in other areas, the fact would give them a high degree of confidence in the predictions of the theory, about the possibility or impossibility of the trip in time.

Other theories that would prevent the emergence of temporal paradoxes

Apparently there are other theories that allow the journey to the past and which prevent the paradoxes of time, such as the principle of self-consistency of Novikov, that would ensure that the timeline be maintained consistent, or the idea of parallel universes where the time traveler would be transferred to another universe with another timeline.