Time Machines: Time Travel in Physics, Metaphysics, and Science Fiction

by Paul J. Nahin

This book explores the idea of time travel from the first account in English literature to the latest theories of physicists such as Kip Thorne and Igor Novikov. This very readable work covers a variety of topics including: the history of time travel in fiction; the fundamental scientific concepts of time, spacetime, and the fourth dimension; the speculations of Einstein, Richard Feynman, Kurt Goedel, and others; time travel paradoxes, and much more.

Genres: Science, Nonfiction, Time Travel, Physics, Philosophy

662 pages, Hardcover

First published February 1, 1993

About the author

Paul J. Nahin is professor emeritus of electrical engineering at the University of New Hampshire and the author of many best-selling popular math books, including The Logician and the Engineer and Will You Be Alive 10 Years from Now? (both Princeton).

Reviews

[Max Nemtsov · Rating 5 out of 5]

Поскольку на русском читать ничего все равно невозможно, it's all tainted, попробуем продолжить чтение по программе. Книжка Пола Нейина - занимательная спекулятивная энциклопедия путешествий во времени и собственно самой природы времени, она имеет непосредственное отношение к "роману в работе", где вопрос времени - основной в сюжете. "Попаданцы" - лишь одна разновидность путешественников во времени; здесь целый раздел посвящен беженцам из неприятного будущего в идиллическое прошлое. Чтение прошлого и будущего (без влияния на них) - другой крюк сюжета. Похоже, Пинчон пользовался этой книжкой как шпаргалкой, в общем.

Вплоть до того, что несколько ее персонажей (Мактаггарт, к примеру, или Минковски) выступают фигурами стаффажа в "романе в работе". Мало того: сложные временнЫе конструкции у Пинчона (все эти 'is going to have been past' и 'was going to be future', которые невозможно компактно передать на русском, где время весьма примитивно, взяты непосредственно из того же Мактаггарта, когда тот (лукаво) пытался доказать несуществование времени в 1908 году. Хотя понятно, что с анахронией Пинчон работал с самого начала. Гистерон-протерон у него один из любимейших приемов: "распалась связь времен", как известно, но не только: каузальность как основу рациональности ХХ века он тоже подрывает, вплоть до энтропии. Обратная каузальность (петух кукарекает, но светает не поэтому) у него тоже есть, да и "вечное возвращение" Эрнста Цермело фигурирует. Отдельно радуют проходки по перпендикулярности множественных стрел времени (надеюсь, в следующей книжке этого у него будет больше) и аппараты для рассматривания прошлого и будущего.

В обзорно-теоретической части, кстати, наш автор еще и поднимает вопрос о выносе ума наблюдателя из пространства-времени - в некую область, мы бы сказали, "сознания Будды", и вот это уже становится по-настоящему интересным. Но автор этого не говорит, фактически не заходит дальше выражения "на том уровне, о котором нам ничего не может рассказать физика", т.е. остается целиком в западной позитивистской парадигме и переходит к чему-то там другому. А жаль, поскольку это по-настоящему богатая тема для рассуждений и построения умозрительных моделей (в т.ч. и путешествий во времени, конечно). При этом надо понимать, что ссылается он на шотландца Клемента Мандла, "философа и парапсихолога".

Ну и дорогого стоит фраза Брэдбери, которую я раньше не видел (она из предисловия к книжке, которую я не читал), - она описывает примерно любые человеческие занятия, не только чтение книг или путешествия во времени: "We attend them [спектакли по пьесам Шекспира, в данном случае] to toss pebbles in ponds, not to see the stones strike, but the ripples spread".

[John Jr. · Rating 3 out of 5]

Philosophers and physicists have tackled the idea of time travel from one angle, trying to establish what’s technically or logically possible, what’s forbidden, and why, while science fiction writers have gone at it from another, exploring the dramatic and thematic possibilities. In this book, Paul Nahin has attempted the difficult task of surveying both viewpoints, the factual and the fictional.

For me, the book is problematic in some respects. Nahin attempts to draw some conclusions about the science and the philosophy as he goes, but sometimes these feel poorly founded. And his discussion is sometimes a little cloudy. In reading it, I often wished I were in a classroom where I could ask questions. For instance: What exactly is the difference between changing the past, which Nahin says most thinkers have now ruled out, and merely affecting it, which they believe is allowed? The distinction eventually made sense to me, and after a second reading, Nahin’s treatment of it seems quite clear within the limits of his text, though in commonsense terms it’s still a little confounding. Basically, the idea is that, if I could travel to the past, anything I did there would have to be consistent with the state of the world today. To use a common example, I can’t go back in time and kill my grandfather before my father was born, but I could go back and be the person who introduces my grandfather to my grandmother. Other points, mostly technical, still puzzle me, but that’s in the nature of the material.

Regardless, a vast amount of research has been summarized in this book, ranging from old pulp-magazine stories to scientific papers that were still recent at the time Nahin completed the text. In effect, the book is two surveys in one—combining an overview of the fictional literature with an account of the scientific and (less thoroughly) the philosophical literature—and that makes this a doubly valuable reference. Other writers have done a better job of explicating some of the concepts here, but as far as I can tell, there is no other book like this.

Side notes: I read this as background for a play involving time travel. I’m curious what's in the revised and expanded second edition, but not so much that I want to buy it—apparently it’s available only in hardcover form.

[Derek DeHart · Rating 1 out of 5]

Reading this book is like spending hours upon hours with some kind of physics dissertation that tries to use science fiction to prove the possibility of time travel. The catch is that dissertations usually contain clear hypotheses and proofs, whereas this book goes almost nowhere for 300 pages.

Instead of spelling out concepts, author Paul Nahin instead references entire works inline without any context, as though the reader ought to have digested the entire body of science fiction works on his topics prior to picking up his book. There are ample notes to accompany his text, but these are more of a distraction than guidance when navigating his chaos.

Finally, after pages and pages of exposition and postulation that go apparently nowhere, the book wraps up with a series of "Tech Notes" (presumably intended to provide more concrete and organized information about the theories surrounding time travel and faster-than-light speeds) that replace poorly-utilized literary references with advanced (for the lay person the former portion of this book might attract) mathematics that leaves one feeling stupefied rather than at ease with any clear conclusion.

To be fair to Mr. Nahin, the topics he approaches are advanced exercises in physics and philosophy, and there are aspects of the book that effectively lead the reader into flights of fancy and awestruck speculation; unfortunately, these are as rare in his work as stable wormholes in the universe.

[Andy · Rating 4 out of 5]

Paul Nahin seems to have read almost every thing that every philosopher, theologian, physicist, mathematician and SF or fantasy writer ever wrote about time travel, time reversal, the fourth dimension and the arrow of time, and he thoroughly discusses how those concepts have developed over the centuries. He is a physicist himself and takes the view that time travel, if it is possible, would fulfill the consistency principle (so that future events could be the cause of past events, but could not change past events) but he fairly considers the opinions of those that believe that time travel is impossible because of the "grandfather" paradox, and discusses many stories in which the past is changed. I read the 2nd edition of this book, and I'm looking forward to taking some time to send the author an email with some suggestions for the third edition (and with some corrections for a few typos). If you are interested in the history of time travel, this is the book to read.

[Elisabeth · Rating 5 out of 5]

This book is awesome.
I must say much of the science is beyond me and I found this book to be a difficult read. But totally worth it. Nahin is an entertaining writer, even when discussing the more obscure aspects of special relativity and the theoretical potential for the impossible. Fascinating. Via this book I was introduced to the 'time loaf' concept, which seems to me the most plausible theory of the nature of time. Through this book also I got to re-think my own idea of free will. And even if it's a bit silly, it's exciting to consider time travel and other impossible ideas in the context of real live experimental science.
If you have an interest in science and a bit of an overactive imagination, I expect you will enjoy this book as much as I did.

[Isaac · Rating 4 out of 5]

This book is a collection of every time travel idea and concept of the past hundred years or so. Paul Nahin assembled this book to explain how time travel has worked in those stories and how time travel could possibly work. He starts the first few hundred pages discussing the way fictional stories utilize time travel. He comments on what they did right and what problems each method has analyzing the flaws and offering reason why. The second half of the book contains ways that time travel could be made in the real world and the discussion of the physics of said methods. This book is a great read all though a little lengthy it starts to blur the line between fiction and reality and makes you think the impossible could really happen.

[Nick Gotch · Rating 3 out of 5]

I was expecting more of a physics book when I first opened this but it turned out to be moreso about all the stories of time travel throughout writing history. It mentions tons of references for books, movies, and television shows that centered on time travel and includes a lot of trivia info you probably otherwise wouldn't have known.

It does cover the real science of time travel fairly well as well and the technical appendices are a temporal mechanics student's best friend.

[David · Rating 5 out of 5]

My favorite book!

[Evan Þ. · Rating 3 out of 5]

This literary and scientific analysis of time machines in science fiction was an interesting premise, but longer than its style and organization really carried it.

It's organized around ways of approaching time travel: there're chapters on alternate universes and branching universes and one mutable history and one changeless history; and then chapters on possible methods of time travel. In each chapter, we get some scientific and philosophical exploration illustrated with examples from science fiction stories; and perhaps an overview of how it's been used in science fiction in general.

Unfortunately, that "perhaps" doesn't go far enough. I can't see any unifying thread among the science fiction examples, and the science as such doesn't hold my interest well enough as a central thread through the book. This isn't quite an anthology of examples, but it's approaching that.

On the other hand, it does explain the science well. This's the first time I really understood Tipler cylinders and Goedel rotating universes.

[Ron Me]

Comprehensive overview. Very few errors. A must have for anyone interested in the subject. N.B.: Many of the stories I've recently reviewed here I was first led to by this book.

[Micki James · Rating 5 out of 5]

Fantastic book if you are interested in both the physics of time travel and the science fiction of time machines. Find out which stories are consistent with modern physics and which must be classified as total fantasy. Anything that is entertaining to read and has led me to happy new encounters gets 5 stars in my book. Without this I would probably never have seen Bill and Ted's Excellent Adventure.

[Edward · Rating 5 out of 5]

I always wanted to write this book and now the pleasure of discovering it more than makes up for that broken dream.

[Nihan Sarı · Rating 5 out of 5]

Fizik bilimiyle daha önce ilgilenmemiş okurlara hitap etmeyecektir. Diğerleri ise severek okuyacaklar.