If aliens were ever seen on or near earth then it's likely they came FROM the future even if they are aliens... Since they came FROM a great distance in ORDER for them to get here in a reasonable time they would have to travel faster than light would take to travel the distance. According to relativity(serious science, partly proven)if something travelled faster than light it would move back in time! Even if the aliens used a wormhole(a tunnel in time and space) they would almost certainly go backwards in time!
They would either have to travel at great speeds or use a wormhole as far as our physics suggests. Both these things would greatly distort time or allow time-travel!
So probably either aliens came back FROM the future or humans do... The possibility of time-travel has to be taken seriously because of the work done by theoretical physicists the last few decades. How does time behave in physics?
Time can be slowed down by gravity and high speeds... It's relative so as we advance in technology we can hope to warp time so much we could travel towards the past...
They would either have to travel at great speeds or use a wormhole as far as our physics suggests. Both these things would greatly distort time or allow time-travel!
So probably either aliens came back FROM the future or humans do... The possibility of time-travel has to be taken seriously because of the work done by theoretical physicists the last few decades. How does time behave in physics?
Time can be slowed down by gravity and high speeds... It's relative so as we advance in technology we can hope to warp time so much we could travel towards the past...