Mad about time III. Time machines.

In a recent movie about H.G. Wells’ novel ‘The time machine’ there is a scene where the main actor is asking a virtual librarian about time travel and time machines. The holographic projection with an incredible registers of all the human history answer him that those things are only possible for science fiction. However, there have been real time machines in human history despite of the science fiction record and moreover, it has been believed that real time travel have existed and even some scientific project could be make real the time travel.

Mad about time II. Time travel to the past.

We live in a vertex of past and future time cones. We have seen the past and we know that we will see a part of the future. We even know that is possible to travel to the future but the question is: can we travel to the past?