How to Build a Time Machine [Paperback]

Paul Davies (Author)

Book Description

Release date: March 25, 2003 | ISBN-10: 0142001864 | ISBN-13: 978-0142001868 | Edition: Reprint

With his unique knack for making cutting-edge theoretical science effortlessly accessible, world-renowned physicist Paul Davies now tackles an issue that has boggled minds for centuries: Is time travel possible? The answer, insists Davies, is definitely yes—once you iron out a few kinks in the space-time continuum. With tongue placed firmly in cheek, Davies explains the theoretical physics that make visiting the future and revisiting the past possible, then proceeds to lay out a four-stage process for assembling a time machine and making it work. Wildly inventive and theoretically sound, How to Build a Time Machine is creative science at its best—illuminating, entertaining, and thought provoking.

Editorial Reviews

From Publishers Weekly

Is time travel possible? If so, what manner of machine would one need to traverse this fourth dimension? Covering ground similar to J. Richard Gott's Time Travel in Einstein's Universe, this slim, tongue-in-cheek treatise invokes the primary tenet of Einstein's special theory of relativity that both time and space are elastic to illustrate that time travel, while impractical, is definitely possible. The time travel mechanisms Davies (The Fifth Miracle) envisions are dramatically different from the devices that SF authors H.G. Wells and Ray Bradbury have employed in their fiction. All that's needed to travel to the future, noted theoretical physicist Davies asserts, is a little help from gravity and a spaceship that can reach speeds just under the speed of light. Traveling to the past is a trickier task, however, and Davies spends the bulk of his book explaining the components needed to construct a wormhole (a black hole "with an exit as well as an entrance"). Despite the author's penchant for diagrams and his habit of highlighting and repeating his major points, readers will struggle to accept some of his more difficult and extreme propositions such as the existence of an exotic matter possessing antigravitational properties, which is vital to his construction of a wormhole. While Davies's discussion of the paradoxes inherent in time travel and of the physical laws that seem to prevent it is both thought provoking and accessible, his limited focus on wormholes may disappoint those hungering for a broader discussion of time travel technology.

Copyright 2002 Cahners Business Information, Inc.

--This text refers to an out of print or unavailable edition of this title.

From Scientific American

Is time travel possible? Yes, says Davies, who recently retired (in his early 50s) as professor of mathematical physics at the University of Adelaide in Australia to concentrate on his writing. But "a moment's thought uncovers some tricky questions." Whereupon he discusses lucidly and engagingly both the concepts of physics that establish the possibility of time travel and the tricky questions. You could reach the future "by simply moving very fast." For visiting the past, the most popular proposal is a wormhole, "a sculpture in the structure of space that provides a shortcut between two widely separated spaces." There may be "cosmic taboos," though, that make time travel forever elusive.

Editors of Scientific American --This text refers to an out of print or unavailable edition of this title.

See all Editorial Reviews

Product Details

• Paperback: 144 pages
• Publisher: Penguin Books; Reprint edition (March 25, 2003)
• Language: English
• ISBN-10: 0142001864
• ISBN-13: 978-0142001868
• Product Dimensions: 7.9 x 5 x 0.4 inches
• Shipping Weight: 2.1 ounces (View shipping rates and policies)
• Average Customer Review: 4.2 out of 5 stars  See all reviews (24 customer reviews)
• Amazon Best Sellers Rank: #376,390 in Books (See Top 100 in Books)
  • #55 in Books > Professional & Technical > Professional Science > Physics > Time

More About the Author

Paul Davies is an internationally acclaimed physicist, cosmologist, and astrobiologist at Arizona State University, where he runs the pioneering Beyond Center for Fundamental Concepts in Science. He also chairs the Search for Extraterrestrial Intelligence Post-Detection Taskgroup, so that if SETI succeeds in finding intelligent life, he will be among the first to know. The asteroid 1992OG was officially renamed Pauldavies in his honor. In addition to his many scientific awards, Davies is the recipient of the 1995 Templeton Prize--the world's largest annual prize--for his work on science and religion. He is the author of more than twenty books, including The Mind of God, About Time, How to Build a Time Machine, and The Goldilocks Enigma. He lives in Tempe, Arizona.

Most Helpful Customer Reviews

43 of 50 people found the following review helpful

3.0 out of 5 stars Not the best book out there June 8, 2002

By "jinde"

Format:Hardcover

First of all, If you have already read some books on black holes and worm holes/time travel, you probably won't learn much from the book as it is non-mathematical (the only equation is E=mc^2) and introduces only the fundamental aspects of time, space and time travel. Otherwise you might want to take a moment and read on before buying it.

I understand that most authors spend a lot of time on their books, even though the books themselves might not stand out in the end. As such, I am really reluctant to give their books any low grade. But this book really has little to deserve my praise, so I give it a 3.

The book is rather short. English is not my native language, but I still finished it in 3 hours in a bookstore.

I feel the book is divided into 3 parts: first part introduces relativity (including things like light and gravity) and black holes; second part discusses how to construct (at least in theory) a worm hole that can be used as a time machine; and the last part deals with the paradoxes and implications of time travel.

I think the author was not sure what level of audience he's targeting. The first part is easy to understand for everyone. But that is not what audience want to learn from the book--they want to know about time machines. So they turn to the last two parts, which may be a bit hard for them. For instance, the author mentioned rotating black holes, but nowhere in the book he explained what they are. He also mentioned their ring-like singularity but he didn't even put a drawing to help readers to understand. I am quite serious about science and I read a few books on the subject so I know what rotating black holes are like. But I really don't think everyone knows about them and the author shouldn't assume thate either because the first part limits the book to general audience. There are many more examples like this in the book.

This actually is embedded in a more serious problem: the book is generally lacking much needed information and explanation. When I read about black hole I expect to find the words "event horizon" and "singularity". Actually I found the latter, but the first is only vaguely described and never stated directly. When the book talks about gravitational lensing, it would be really helpful to include a drawing to show how it works, but you can't find that either. How about the Casimir Effect that creates negative energy? (negative energy is explained in the book.)The author says it relates to virtual photons, but what are those? And honestly I don't think the author clearly explains the Casimir Effect either. He simply states the things he needs and expect you to take them for granted. But if you give a little thought on the subject, I am sure that you will have tons of questions unanswered. So after reading it you might not have a firm grasp on the subject.

Also around page 15 (might be 13 or 17), I believe the author made a mistake. The book says if you half the diameter of the earth the gravitational force on the surface of the earth is 2 times as strong. This is NOT true. It should be 4 times as strong because force F is inversely proportional to the square of the distance. [F=GMm/(R^2), where G is the gravitational constant and M's are the attracting masses, R is the distance between the masses, which in this case is halved] I am sure the author overlooked this, but since it is such a fundamental thing and he highlighted the paragraph in the book, there is no excuse for the mistake.

The reason that I am giving it 3 stars and not less is because the last two sections of the book are interesting to me and I learned something (although not much) from reading them. I am not saying that you will not like it, in fact many reviews before mine gave it a 5 star. But I strongly recommend that you first take a look at it, in a bookstore perhaps. Maybe you can finish the book like I did if you have the time.

Because I didn't read that many books on the subject, I can't tell you which ones are the best. But for a better description on the subject (black holes/worm holes/time travel) you might find Clifford Pickover's "Black holes: a Traveler�s Guide" interesting.(New York: John Wiley & Sons, Inc. 1996.) It has some equations but they are not that hard to understand, the book introduces probably everything you ever need to know about black holes. You can find more about black holes from Stephen Hawking's "A Brief History of Time", and from the time travel authority: Kip Thorne's "Black Holes & Time Warps" (but this one is a bit harder). I also liked Brian Greene's sections on general relativity and quantum mechanics in his "The Elegant Universe", he explains the subject so clearly and provides so many insights. (If you have a question then you can be sure to find the answer in the next paragraph. A perfect 5 star if I were to rate it) John D. Hawley & Katherine A. Holcomb's "Foundations of Modern Cosmology" (New York: Oxford UP, 1998.) is also an excellent book, but I suggest you borrow it from library since it is rather expensive ($50 I believe, it has a section on black holes, probably like 30 pages, it also has a chapter on relativity).

24 of 29 people found the following review helpful

5.0 out of 5 stars Short, easy, deep and beautiful. What else? March 2, 2002

By Paulo C. Rios Jr. VINE™ VOICE

Format:Hardcover

Paul Davies is a great author. But some readers may find some of his books long as books usually are. This one not. It is short, but clear cut goal-oriented and conceptually deep. You will understand some concepts that seemed so confusing too you. Most of all, you will see things under a different light. Physics at its best. Just a warning: you can read it in an afternoon, but you will probably become so interested that you will want to spend a lot more time with wonderful books and subjects like these. The fun will last only about 150 pages.

11 of 13 people found the following review helpful

4.0 out of 5 stars a valuable starting point May 29, 2003

By Robertomelbourne

Format:Paperback

Davies has attempted a very difficult task: how to write a brief and easily understood account of the physics and mathematics underpinning the idea of time travel.

In the main part Davies succeeds admirably. It is clearly not that simple to condense highly complex mathematical equations, and concepts of and about quantum physics to a level that the ordinary person will not only grasp but perhaps think about.

The book is effectively divided into two parts. The first is a synopsis of the theories underpinning time travel. In this section Davies provides a speedy overview of the history of thinking about time travel, the development of the theories, and he attempts to at least conceptually work through the possibilities and problems associated with the main theories that hold currency.

In the second part, Davies sets out the mechanics of how to build a time machine. The content contained in is part, not matter how hard Davies tries, and despite its brevity, was very difficult for this reader to understand. Having no background in pure physics, I became a bit lost in places. But struggling through out, it is still informative and challenging.

Overall, the book is a valuable starting point for the general person to get a grip on this though provoking topic.