Temperal visitors are not only possible,but probable. Most people would like to believe that these visitors would be just that,visitors. However, what other motivation would you need to time travel. Historians may travel back to see how things really were to keep more accurate detail for schools or libraries. Perhaps our decade is one big ammusement park for the masses of the future. Another possability that these people could be going back in time to warn us of some danger to follow. Forget the thought of any rules for time travel that might create a paradox or even a new time line. Perhaps even H.G. Wells truly was a time traveller. His early works described wireless telephones since before world war one. Even before 1912 he had written the idea of flying winged aircraft dropping bombs right into the heart of london, then comes along WWII. If there was any man who has disrupted time it could have been Mr. Wells. Who could have picked up one of his early works and decided that they would be the first to create such a device. Would this have created a loop for the introduction of new technologies. Perhaps these time travellers may even be humanity so advanced and evolved to be from the far future. Perhaps we have evolved into little green men and those flying saucers are actually time travellers. They come back to do anthropology studies on their distant ancestors.Us. Or perhaps something sinister such as working on our DNA in this time to improve themselves in the future, thereby introducing a new timeline of healthier and stronger bodies for themselves. Maybe the visitors aren't even from the future, perhaps they come from the long lost past. A few million years ago a thriving advanced civilization decided to check their own future. They travelled forward in their history and watched as it self destructed, and we have become their effort to rebuild that once glorious past. Time can't be broken but just maybe it can be bent. So if you really sit down and look at it, time travel has just become a major reality. It could be just as simple as closing your eyes and hunting the great dinosaurs or walking on distant Alpha Centauri
