Faster-than-light. (FTL) Time Travel

This is one of those questions that has baffled me since I can remember. I think about it a lot. It has nothing to do with the feeling of having lived before, reincarnation. 

When I talk about time travel I mean a time machine, that lets you travel faster than the speed of light. Does someone in the future invent some sort of machine that can make us travel through time and space?

Is it possible and would it explain, sightings of...   ghosts, aliens, big foot, flying saucers, a parallel universe, etc. Are time travellers really us from the future or another life form, from another world, a dimension, another time?  Only to be spectators, unable to engage with and unable to acknowledge us, seemingly to disappear or mysteriously leave, walking through walls or taking off at high speeds across the sky.

If time travel does ever become invented in the future, why haven't we been introduced, already? Does no one want to come back to this time in history. We wouldn't blame them, if they didn't.

Time travel is the concept of moving between different points, analogously in time through space.

Alberti Einstein developed a theory called 

"Special Relativity" 

time and space being the same aspects of the same thing. The speed limit is 300,000 kilometres per second, or 186,000 miles per second, the speed of light through empty space. Nothing can go faster, so... I'm thinking worm holes.  But that is not a machine.

I think about things like this, a lot! It has nothing to do about reincarnation, that's another blog. 

Dog Brindle