Time travel theory

I have a new theory about time travel. #

But first a question — if it’s possible to travel back in time, in the future, why haven’t we been visited by time travelers already? Of course maybe we have been, but for some reason they’re not visible to us, they’re in another dimension or something like that. #

But assuming we could experience their presence if they were here, maybe it’s because in order for a time traveler to land here, we need to have a certain technology that we don’t yet have, that acts as a receiver of sorts. #

And the day when that receiver is invented, perhaps unknowingly to the inventor, all of a sudden their house or apartment turns into a religious and historic shrine, a Disneyland or Fort Sumter of time travel. The place is instantly transformed into Wailing Wall, Ground Zero, or Mount Rushmore. #

I imagine there is already a science fiction book based on this premise. #