It looks like somebody doesn't understand relativity. Our
current understanding of physics dictates that we cannot travel
faster than the speed of light. Even with an extremely fast
acceleration, from at least one reference frame, if an object
has mass, it will never reach the speed of light. Accelerating
an object with a mass's speed to the speed of light would
require an infinite (read: extremely massive) amount of energy
that we just aren't capable of producing. Sure putting a
gravitational field in front of an object would produce a force,
but just how massive would would the object have to be to
produce a gravitational field that produces enough force to
actually accomplish something within a limited amount of time?
It would appear that the only hypothetically feasible object to
use would be a black hole, and even those are not known well
enough to do anything useful with them. It's useless talking
about how we are going to accomplish time-travel if we don't
even have all of the (mathematical) tools avai