What type of time travel is used in A Christmas Carol? Neil deGrasse Tyson and comic co-host Chuck Nice answer fan questions on time travel, paradoxes, and wormholes with theoretical physicist, Brian Greene. Did Ebenezer Scrooge get pulled through a wormhole? How did people think about time travel before Einstein? How did the special theory of relativity change how we think about time? Discover time dilation and how speed and gravity affects an object’s passage of time. What type of time travel was Charles Dickens using? Learn about the possible paradoxes of traveling and meddling with the past. Is there one immutable timeline or many timelines in a multiverse? Do we have free will? What is time to a photon traveling at the speed of light? How would we police time travel if it were possible? Will we even have time travel in the future? If time travel gets invented, why are we not overrun by tourists from the future? Which films depict time travel best? How are cells affected by time travel? We explore the movement of information in and out of black holes, string theory, and tachyons. Could we theoretically time travel to before the big bang? Finally, is there even a realm to travel to before the Big Bang? NOTE: StarTalk+ Patrons can watch or listen to this entire episode commercial-free. Get the NEW Cosmic Queries book (5/5 ⭐s on Amazon!): https://amzn.to/3dYIEQF Support us on Patreon: https://www.patreon.com/startalkradio FOLLOW or SUBSCRIBE to StarTalk: Twitter: http://twitter.com/startalkradio Facebook: https://www.facebook.com/StarTalk Instagram: https://www.instagram.com/startalk About StarTalk: Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up! #StarTalk #neildegrassetyson Timestamps: 00:00 - Introduction 02:50 - “A Christmas Carol:” Time Travel before Relativity 05:40 - Time Dialation & Special Relativity 11:20 - Interacting with the Past & Changing the Timeline 17:15 - Tachyons, Destiny, & Immutable Timelines 20:30 - Time at the Speed of Light 22:45 - Hawking Time Travel Conjecture 24:40 - Best Time Travel Movies 30:00 - Information & What Time Travel Would Look Like 38:37 - Paradoxes & Parallel Universes 42:45 - Moving Through Spacetime 46:14 - What’s a Tachyon? 49:10 - Time Before the Big Bang 51:24 - What Type of Time Travel in “A Christmas Carol”