The relative resemblance of some famous people and pictures of their unknown look-alikes from the past has been a source of increasing internet conjecture (as the internet has largely fueled such conjecture). The idea that people that look alike are really the same people has led to some further outlandish theories. Time travel, reincarnation and assuming a similar appearance, and immortality are three common ones.
This recent Facebook post ups the ante; “GMO Cloning.”
If the resemblance between old photograph subjects and famous contemporaries have convinced you of the existence of time travel, then perhaps it is a good time to learn about the psychological concept of pareidolia.