One of the major objections to the idea that time travel is possible is the apparent fact that we haven’t been visited by tourists from the future. If travel to the past is possible, it’s likely that future historians may be tempted to take advantage of it, that terrorists or criminals may travel back in time to alter history, that someone would go back to visit their ancestor… and that, with those and so many other possible motives, it’s unlikely that the technology would never be used.
The most obvious answer to why we haven’t seen travellers from the future is that backwards time travel is either impossible or never gets invented. Maybe humanity dies out before inventing it, for example. But obviously we don’t want humanity to die out, and time travel is too cool to go uninvented, so what are we left with?
Fear not… all of your twisted sci-fi dreams may yet come to pass. Here are some possible explanations for why we haven’t met any time tourists yet…