The Bootstrap Paradox

imagine one day you receive a mysterious package there is no note saying who sent the package or why it's been sent to you confused but curious you open the package to find a book how to build a time machine you dismiss it at first as some kind of joke but after reading through the book you start to believe that it might actually be real you decide to give it a go and start collecting all the materials and items you need takes a long time but after 10 years and several failed attempts you finally build a working time machine in all this time you never find out where the book came from or why it was sent to you but then it suddenly hits you you grab the book and jump into your time machine [Music] you travel back in time ten years leaving the book for your younger self to discover but where did the book originally come from you can only build the time machine if you discover the book but you can only discover the book if you build a time machine it appears that the book has not been created by anyone and is stuck in an endless causal loop this is known as the bootstrap paradox the bootstrap paradox works with an object like the book a piece of information or a person imagine you go further back in time and meet a young Albert Einstein before he was famous you tell him about the theory of relativity which he later publishes and many years later you learn about in school so who here came up with the theory or perhaps she decided to go back to the late 1500s to meet a young William Shakespeare however you're not able to find him anywhere and no one has even heard of him luckily you brought the complete works of Shakespeare back in time with you and decide to start publishing his works as your own in other words you are and always have been William Shakespeare the bootstrap paradox goes against our understanding of cause-and-effect an event a in the past causes event B in the present which will cause event C to happen in the future time passes in a straight line from A to C with the future always uncertain and dependent on our actions in the past and present in the paradox event C causes event A which would mean that the future event has already happened this obviously doesn't fit with our linear understanding of time suggesting that the past present and future are all equally real boss we only subjectively experienced the present moment this has big implications for free will does our time traveler have the choice to build the time machine or is it already determined that he will build a time machine otherwise how else could he have received the book one possible solution is the idea of multiverse time travel when our time traveler goes back in time they arrive in a different universe a duplicate of the one they left which is identical up to the time they arrived they are then free to act in this new universe without affecting the original this would not be a true causal loop but could explain how it would be possible to travel back in time and change past events a further problem with the bootstrap paradox is that it appears to violate the second law of thermodynamics an object stuck in a time loop such as the book will age and eventually wear down it's entropy will increase to the point where it can no longer be used to build the time machine we could suppose that entropy is somehow reversed by time travel so that the book is restored to its original state however it's not clear what an object's original state is when it doesn't have a clear origin to begin with and would this also apply to the time traveler restoring him to his original state of ten years ago this would make time travel back further to the 1500s impossible this is of course all hypothetical paradoxes like this and the grandfather paradox demonstrate why some scientists such as Stephen Hawking believed that time travel to the past is impossible but what do you think will we one day be able to travel back in time and if so how can we account for the bootstrap paradox let me know down in the comments [Music] thanks for watching don't forget to subscribe and if you want to watch more paradox videos then check out this playlist by clicking over here for something a bit different you can watch my previous video on why people believe in astrology and psychics by clicking here see you next time

Channel: Smart by Design

Views: 2,631,953

Keywords: bootstrap paradox, bootstrap, paradox, the problem with time travel, time travel, causal loop, is time travel possible, can we travel back in time, time machine, information paradox, ontological paradox, how to build a time machine, cause and effect, time, free will, freewill, multiverse, entropy, arrow of time, grandfather paradox, smart by design, time travel paradox, temporal paradox, bootstrap paradox explained, time travel explained, second law of thermodynamics

Id: Pp5VjZ3uhMc

Length: 5min 2sec (302 seconds)

Published: Sat Dec 09 2017