The bootstrap paradox, or ontological paradox, is a paradox of time travel that refers to scenarios whereby items or information are passed from the future to the past, which in turn become the same items or information that are subsequently passed from the past to the future - this creates a circularity of cause-effect such that the items or information have no discernible origin. Thus, the paradox raises the ontological questions of where, when and by whom the items were created or the information derived.
After information or an object is sent back in time, it is recovered in the present and...