Editing Temporal paradox (section)

===Bootstrap paradox===
A bootstrap paradox, also known as an '''information loop''', an ''information paradox'',<ref name="Everett" /> an ''ontological paradox'',<ref name="smeenk">{{Citation |last1=Smeenk|first1=Chris|last2=Wüthrich|first2=Christian|editor-last=Callender|editor-first=Craig|contribution=Time Travel and Time Machines|title=The Oxford Handbook of Philosophy of Time|year=2011|publisher=Oxford University Press|isbn = 978-0-19-929820-4|page=[https://books.google.com/books?id=PrapBAAAQBAJ&lpg=PP1&pg=PT720 581]}}</ref> or a "predestination paradox" is a paradox of time travel that occurs when any event, such as an action, information, an object, or a person, ultimately causes itself, as a consequence of either [[retrocausality]] or [[time travel]].<ref name="Smith">{{cite web |url=http://plato.stanford.edu/entries/time-travel/index.html#CauLoo |last=Smith|first=Nicholas J.J.|date=2013 |title=Time Travel |website=Stanford Encyclopedia of Philosophy |access-date=June 13, 2015}}</ref><ref name="Lobo" /><ref>{{cite book|last=Rea|first=Michael|title=Metaphysics: The Basics|date=2014|publisher=Routledge|location=New York|isbn=978-0-415-57441-9|edition=1. publ.|page=[https://books.google.com/books?id=v1IsAwAAQBAJ&lpg=PP1&pg=PA78 78]}}</ref><ref>{{cite book|last1=Rea|first1=Michael C.|title=Arguing about Metaphysics|date=2009|publisher=Routledge|location=New York [u.a.]|isbn=978-0-415-95826-4|page=204}}</ref>

Backward time travel would allow information, people, or objects whose histories seem to "come from nowhere".<ref name="Smith" /> Such causally looped events then exist in [[spacetime]], but their origin cannot be determined.<ref name="Smith" /><ref name="Lobo" /> The notion of objects or information that are "self-existing" in this way is often viewed as paradoxical.<ref name="Lobo" /><ref name="Everett">{{cite book|last1=Everett|first1=Allen|last2=Roman|first2=Thomas|title=Time Travel and Warp Drives|date=2012|publisher=University of Chicago Press|location=Chicago|isbn=978-0-226-22498-5|pages=[https://books.google.com/books?id=Dm5xt_XbFyoC&lpg=PP1&pg=PA136 136–139]}}</ref><ref>{{cite book|last=Visser|first=Matt|title=Lorentzian Wormholes: From Einstein to Hawking|date=1996|publisher=Springer-Verlag|location=New York|isbn=1-56396-653-0|page=213}}</ref> A notable example occurs in the 1958 [[science fiction]] [[short story]] "[[—All You Zombies—]]", by [[Robert A. Heinlein]], wherein the main character, an [[intersex]] individual, becomes both their own mother and father; the 2014 film ''[[Predestination (film)|Predestination]]'' is based on the story. Allen Everett gives the movie ''[[Somewhere in Time (film)|Somewhere in Time]]'' as an example involving an object with no origin: an old woman gives a watch to a playwright who later travels back in time and meets the same woman when she was young, and shows her the watch that she will later give to him.<ref name="Everett" /> An example of information which "came from nowhere" is in the movie ''[[Star Trek IV: The Voyage Home]]'', in which a 23rd-century engineer travels back in time, and gives the formula for [[list of Star Trek materials#Transparent aluminum|transparent aluminum]] to the 20th-century engineer who supposedly invented it.