How Alien Space Travel May Work

When looking at the theory of relativity, we’re often told that a crew on-board a colony vessel would have to travel at incredible speeds, even faster than the speed of light or else they would have to live for several thousand years aboard their respective colony ships and withstand entire lifetimes on-board their quickly aging ships.  Theories of relativity do, however, have a loophole that could render space travel for even modestly technologically advanced craft to travel at incredible speeds without having to withstand such seemingly impossible voyages.  The concept is one that is rarely visited by modern science fiction, but could work easily within the realm of science and provide seemingly limitless travel for those wishing to take to the stars.

The theory of relativity states that no object can accelerate to the speed of light, but it does not say that something cannot move almost the speed of light.  In fact, according to acclaimed physicist Stephen Hawking, a vessel using even conventional propulsion methods could accelerate continuously for six years and quite quickly approach the speed of light.  And as time went on, this acceleration would allow travel through the vacuum of space even allowing the ship to quickly move to speeds where time was affected.  The theory of relativity gets its name from the interaction between an object moving at or near the speed of light’s time passage relative to the speed of objects around it.  If someone were traveling on a ship that was just three or four miles under the speed of light and threw a ball on the vessel in the direction they were traveling at nine or ten miles per hour, would the ball break the laws of physics?  The answer is no.  Astounding as it may sound, the laws of physics dictate that time would move far slower on the vessel moving at such an incredible speed.  So as the crew went about their daily lives waiting to arrive at their destination, they would be moving at approximately one one-hundredth the speed of the universe that was remaining completely still.  So if someone inside a massive colony ship were to throw a ball forward on this ship, it would actually take days or even weeks worth of “normal” time to reach its destination even if it seemed to be moving at normal speed to those on-board the ship.

What does this mean in practical terms?  An alien colony ship wouldn’t necessarily have to move past the laws of known physics in order to get from a distant planet to Earth within a reasonable amount of time, but the amount of time passed on its home planet would be hundreds of times faster than it would be for those on-board the ship.  In other words, interstellar travel at near light speeds would be quick for those on ships, but would have to operate independently from “home base” as the world they came from eventually evolved technologically and culturally far beyond the world they had left behind.  A year on a near light speed ship could be a hundred years on their home world.