## If time travel is possible, does it mean it has already been used?

Author: thomas.godart

Published: 2015-07-28

Themes: #Quora #answer

Words: 155

"**If time travel is possible**", therefore... what?

Following Nick Bostrom's "simulation argument" formulation ( Simulation hypothesis ), the "time traveling argument" could be expressed like that:

If in the universe time traveling is possible, then modifying the past is also possible, then creating new branches of time is also possible, then at least 1 of the following propositions have to be true:

*the fraction of living species in the universe that reach the point where they can achieve time traveling is close to zero,**the fraction of the living species in the universe that are interested in time traveling is close to zero,**the fraction of the branches of time that have been created by time travel is close to one.*

So if 3) is true,

- therefore we are very likely living in a branch of time that was created by time travel,
- therefore it's very likely that
**our past has been already modified**by time travel

Also published at: https://www.quora.com/If-time-travel-is-possible-does-it-mean-it-has-already-been-used/answer/Thomas-Godart