I'm a fan of Michio Kaku, thus I'm hesitant to offer the following in so great a company as have assembled to comment here:
it is our primitive understanding of 'time' that limits our imgination of the possibilities. The universe is first considered spatially vast, then the light comes on and one realizes that it is not the spatial separation but the temporal limits of our current technological abilities that hold sway. Perhaps, in the not so distant future, we will come to have a better conceptualization of time and how it is integrated with spatial variables. Since we sense nothing in the present of the phenomena we measure, and have no inkling of how to measure that which is coming to us from the future, we're stuck with a penumbra of present cobbled together through our measurements of past events.
Uh, yeah, what he said.