So, I had the Science Channel on in the background. Again. They were discussing relativity and time dilation. Then the distance to Alpha Centauri came up. And space travel.
My brain mashed those together and came up with this...
What if the only way we humans can travel to distant stars/planets is to lose our physical forms?
As is the intent of all my "what ifs?", feel free to interpret this in any way you choose.