text: do you believe that if you travelled faster than the speed of light....? you would go back in time? or would you just being going really really fast? just 60 years ago the speen of sound was the limit, and just 100 years ago we could not fly at all. i think the really fast is true. it could be possible, although i doubt if you could actually replace relativity with some other theory that could allow that. so for now it's not possible maybe in future.  i believe that because think about it before relativity we all thought that time was constant.   plus even if we can't reach speed of light, we might be able to get close to it which can let us travel farther cause of time dilation. i don't think you could go back in time though.