With the latter could refute those who in respect of travel to the past, they speak of the paradox of who kills his own grandfather when still was a boy and that as a consequence of that Act could not have existed in the future to the not being able to be born. However this paradox does not exist in reality, because traveling to the past automatically change universe. I.e. it is not necessary to kill none of our ancestors. More information is housed here: CMO of PEMCO. To be each one of us a source of energy that radiates its influence through our thoughts towards the entire universe in general and towards the people that surround us in particular (call them those who inhabit the planet Earth to exemplify) action that we print to our thoughts in America will directly influence the development of those living in Asia, because all beings who inhabit the universe are essentially one only partitioning for millions of people, but connected mentally. With the above I mean in the hypothetical case that within 1,000 years the man invented a spaceship that could travel at the speed of light and decided to move to the past, I wouldn’t need to touch the Land, with the only echo enter Earth’s atmosphere still remaining by an only second, such an act would influence to change the fate of all mankind. Because that only second would have been sufficient to introduce the influence of the power of his thoughts in this universe of the past, which did not have their presence until then.
With this I repeat what others have already said: one could travel to the future and return it without that modify its present, but instead could never return to the same present if you travel to the past, by what you’ve already specified. And here to introduce another hypothesis: the destination is not one only, they are infinite. As many as parallel universes exist.