It can be difficult to explain, but essentially the closer you get to the speed of light, the 'slower' time goes when compared to someone 'standing still'.
If I head out for 24 hours away from the Earth at 50% the speed of light and return the next day, decades will have passed on Earth. Yet my reality and watch will say that I've only been gone a day...
Interesting, I am no physics major so I will just have to believe that you are correct.