"Light can bend gravity. Light can bend space-time fabric. When space-time fabric bends, two points at the ends chosen, start to come closer to each other. For space-time loop to exist, bending should be so strong that two points lie on the single point. They get merged to one-another. Then, there will be an existence of loop. Only black holes have the ability to merge two points and form a space-time loop. Till now, it is not possible."
(Light cannot bend gravity to such an extent. Rotating laser beams can bend fabric up to some large extent.)
Until you close the loop you will always be in the past and I will always be in the future. Until you bend space-time you wil be last. Even though I am Last.
