{"id":4940,"date":"2019-05-03T05:00:07","date_gmt":"2019-05-03T12:00:07","guid":{"rendered":"http:\/\/markreads.net\/reviews\/?p=4940"},"modified":"2019-05-03T05:44:02","modified_gmt":"2019-05-03T12:44:02","slug":"mark-reads-the-science-of-discworld-iii-chapter-8","status":"publish","type":"post","link":"https:\/\/markreads.net\/reviews\/2019\/05\/mark-reads-the-science-of-discworld-iii-chapter-8\/","title":{"rendered":"Mark Reads &#8216;The Science of Discworld III&#8217;: Chapter 8"},"content":{"rendered":"<p>In the eighth chapter of <i>Darwin\u00e2\u20ac\u2122s Watch<\/i>, I get to talk about TIME MACHINES! Intrigued? Then it\u00e2\u20ac\u2122s time for Mark to read <i>The Science of Discworld III<\/i>.<span class=\"Apple-converted-space\">\u00c2\u00a0<\/span><!--more--><\/p>\n<p>Oh, y\u00e2\u20ac\u2122all, this was GREAT. I knew from past <i>Science of DIscworld<\/i> books and from a very, VERY basic understanding of general relativity that time travel was theoretically possible, but all <i>this<\/i>? This was so much fun to read as someone who has devoured science fiction since I was a kid. Time travel has been represented in so many different ways since the incarnation of these types of stories. (And I should also note that I love time travel that <i>doesn&#8217;t<\/i> focus on or feature any science. <i>Kindred<\/i> by Octavia Butler, for example, is one of my favorite time travel books, and it\u00e2\u20ac\u2122s just a device. It\u00e2\u20ac\u2122s never explained.) This chapter focuses entirely on the actual mechanics of traveling through time, and I AM SO INTO THIS.<span class=\"Apple-converted-space\">\u00c2\u00a0<\/span><\/p>\n<p>So, let\u00e2\u20ac\u2122s start with this: the closed timelike curve, which is what is needed for an object to return to its own past. Accepting that this is required of time travel\u00e2\u20ac\u201dwhich is interesting, because what if someone <i>only<\/i> wanted to travel ahead in time and never back to their past?\u00e2\u20ac\u201dthe authors run us through some of the more \u00e2\u20ac\u0153feasible\u00e2\u20ac\u009d methods of time travel. I use \u00e2\u20ac\u0153feasible\u00e2\u20ac\u009d lightly here, since the book openly addresses the fact that all of these methods aren\u00e2\u20ac\u2122t actually possible yet. The first of those methods: black holes, white holes, and wormholes! All things I\u00e2\u20ac\u2122ve seen in some form in SF novels. (It\u00e2\u20ac\u2122s also truly amazing that I get to read this book just after the first photo of a black hole was ever published. THAT IS SO COOL, I love science.) But the authors do a great job of setting up my understanding of black holes so that each of the pieces that could lead to possible time travel make sense AND make it show how ridiculously difficult it would be to pull it all off. We are certainly not technologically advanced enough as a species to just <i>build<\/i> a black hole. Also, I\u00e2\u20ac\u2122m a bit of a cynic about humans ever possessing this power. Leave it up to some terrible tech bro to utilize this for localized instant travel and then our whole planet gets sucked into a black hole because while that\u00e2\u20ac\u2122s probably physically impossible, IT IS SPIRITUALLY QUITE BELIEVABLE. Anyway, a wormhole allows for \u00e2\u20ac\u0153matter-transmission,\u00e2\u20ac\u009d but not exactly a time travel device. And that\u00e2\u20ac\u2122s where this is proposed:<\/p>\n<blockquote><p>The idea is to leave the white end of the wormhole fixed, and to zigzag the black one back and forth at just below the speed of light. As the black end zigzags, time dilation comes into play, and time passes more slowly for an observer moving with that end.<span class=\"Apple-converted-space\">\u00c2\u00a0<\/span><\/p><\/blockquote>\n<p>So, it\u00e2\u20ac\u2122s a more <i>technical<\/i> example of time travel, and I don\u00e2\u20ac\u2122t know how you\u00e2\u20ac\u2122d fine tune something like that. How much further into the future must your starting be? Either way, this theoretical travel doesn\u00e2\u20ac\u2122t allow travel \u00e2\u20ac\u0153back past the time barrier,\u00e2\u20ac\u009d or some time <i>after<\/i> humans constructed the wormholes. So, not all that helpful, is it? You couldn\u00e2\u20ac\u2122t even travel back to stop the construction of the wormholes in case that sets in motion some sort of terrible timeline!<\/p>\n<p>There are magnetic wormholes, too, which require exotic matter, and this is already way over my head and currently impossible. (Currently. Because when this book was written, we hadn\u00e2\u20ac\u2122t seen a photo of a black hole!!!) And if we can\u00e2\u20ac\u2122t even make a black hole now, how are we gonna make a <i>rotating<\/i> black hole that\u00e2\u20ac\u2122s connected to \u00e2\u20ac\u0153infinitely many different regions of spacetime\u00e2\u20ac\u009d? Also, how would we program it to land in the universe we wanted? WHAT IF WE WENT TO THE WRONG UNIVERSE.<span class=\"Apple-converted-space\">\u00c2\u00a0<\/span><\/p>\n<p>Basically: this chapter continued to give me ideas for super messed up science fiction stories, and that\u00e2\u20ac\u2122s a perfect segue to the brilliance that science fiction writers came up with shit that is not all that far from our current understanding of reality. Because <i>space<\/i> can travel faster than light, and there\u00e2\u20ac\u2122s an actual theory of how time travel and faster-than-light travel could work by warping spacetime to form a \u00e2\u20ac\u0153mobile bubble\u00e2\u20ac\u009d around an object and then make it surf a gravitational wave while INSIDE that bubble.<span class=\"Apple-converted-space\">\u00c2\u00a0<\/span><\/p>\n<blockquote><p>The SF writers were right. There is no relativistic limit to the speed with which <i>space<\/i> can move.<\/p><\/blockquote>\n<p>I LOVE THIS. And I know this is something that was discussed many times as I made my way through the entirety of <i>Star Trek<\/i>, but that show got a LOT of shit right through imagination and prediction. So, is the future of travel a superluminary highway? Linked wormholes? Warp drives, which would probably require an energy level that is \u00e2\u20ac\u015310 billion times the mass of the known universe\u00e2\u20ac\u009d in order to craft that mobile bubble? WHO KNOWS. And that\u00e2\u20ac\u2122s not even addressing the bent space method of travel using bent-light in the shape of a ring!<\/p>\n<p>All this to say: What if the universe <i>does<\/i> prevent paradoxes from existing? What if time travel will forever remain a theory because of what Hawking proposed? Argh, this is so frustrating and fun to think about, I swear.<\/p>\n<p>https:\/\/www.youtube.com\/watch?v=FqObsYdP0aY<\/p>\n<p><b>Mark Links Stuff<\/b><\/p>\n<p>&#8211; <strong><a href=\"https:\/\/www.markoshiro.com\/blog\/2018\/12\/19\/the-anger-is-a-gift-paperback-edition-is-out-may-7-2019\">The paperback edition of my debut, ANGER IS A GIFT, is now up for pre-order!<\/a> It comes out on May 7, 2019.\u00c2\u00a0<\/strong><strong>If you&#8217;d like to stay up-to-date on all announcements regarding my books, <a href=\"http:\/\/eepurl.com\/ey636\">sign up for my newsletter<\/a>! DO IT.<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the eighth chapter of Darwin\u00e2\u20ac\u2122s Watch, I get to talk about TIME MACHINES! Intrigued? Then it\u00e2\u20ac\u2122s time for Mark to read The Science of Discworld III.\u00c2\u00a0<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[451],"tags":[463,248,559],"class_list":["post-4940","post","type-post","status-publish","format-standard","hentry","category-discworld","tag-mark-reads-discworld","tag-terry-pratchett","tag-the-science-of-discworld-3"],"_links":{"self":[{"href":"https:\/\/markreads.net\/reviews\/wp-json\/wp\/v2\/posts\/4940","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/markreads.net\/reviews\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/markreads.net\/reviews\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/markreads.net\/reviews\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/markreads.net\/reviews\/wp-json\/wp\/v2\/comments?post=4940"}],"version-history":[{"count":0,"href":"https:\/\/markreads.net\/reviews\/wp-json\/wp\/v2\/posts\/4940\/revisions"}],"wp:attachment":[{"href":"https:\/\/markreads.net\/reviews\/wp-json\/wp\/v2\/media?parent=4940"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/markreads.net\/reviews\/wp-json\/wp\/v2\/categories?post=4940"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/markreads.net\/reviews\/wp-json\/wp\/v2\/tags?post=4940"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}<!-- WP Super Cache is installed but broken. 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