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"Don't believe anyone who tells you that humans will never have efficient technology for backward and forward time travel."

Traveling Through Time
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The future of time travel

Various researchers have proposed ways in which backward and forward time machines can be built that do not seem to violate any know laws of physics. Remember that the laws of physics tell us what is possible, not what is practical for humans at this point in time. The physics of time travel is still in its infancy. While all physicists today admit that time travel to the future is possible, many still believe time travel to the past will never be easily attainable. Don't believe anyone who tells you that humans will never have efficient technology for backward and forward time travel. Accurately predicting future technology is nearly impossible, and history is filled with underestimates of technology:

"Heavier-than-air flying machines are impossible." (Lord Kelvin, president, Royal Society, 1895)

"I think there is a world market for maybe five computers." (Thomas Watson, chairman of IBM, 1943)

"There is no reason for any individual to have a computer in their home." (Ken Olsen, president, chairman and founder of Digital Equipment Corp., 1977)

"The telephone has too many shortcomings to be seriously considered as a means of communication. The device is inherently of no value to us." (Western Union internal memo, 1876)

"Airplanes are interesting toys but of no military value." (Marshal Ferdinand Foch, French commander of Allied forces during the closing months of World War I, 1918)

"The wireless music box has no imaginable commercial value. Who would pay for a message sent to nobody in particular?" (David Sarnoff's associates, in response to his urgings for investment in radio in the 1920's)

"Professor Goddard does not know the relation between action and reaction and the need to have something better than a vacuum against which to react. He seems to lack the basic knowledge ladled out daily in high schools." (New York Times editorial about Robert Goddard's revolutionary rocket work, 1921)

"Who the hell wants to hear actors talk?" (Harry M. Warner, Warner Brothers, 1927)

"Everything that can be invented has been invented." (Charles H. Duell, commissioner, US Office of Patents, 1899)

Science fiction spurred humans to go to the moon. Can it spur them to invent a time machine?

Wouldn't it be a wild world to live in if time travel devices played important roles in the development of humanity—like the computer and the telephone? Mathematicians dating back to Georg Bernhard Riemann (1826-1866) have studied the properties of multiple connected spaces in which different regions of space and time are spliced together. Physicists, who once considered this an intellectual exercise for armchair speculation, are now seriously studying advanced branches of mathematics to create practical models of our universe.

Science-fiction stories about space travel have already inspired humans to travel to the moon. Similarly, will time-travel stories inspire us to create real time-travel mechanisms? Will we ever find a way to overcome the Einstein speed limit and make all of spacetime home?

I wonder what humanity will discover about spacetime in the next century. Around four billion years ago, living creatures were nothing more than biochemical machines capable of self-reproduction. In a mere fraction of this time, humans evolved from creatures like Australopithecus. Today humans have wandered the moon and have studied ideas ranging from general relativity to quantum cosmology. Who knows into what beings we will evolve? Who knows what intelligent machines we will create that will be our ultimate heirs? These creatures might survive virtually forever, with our ideas, hopes, and dreams carried with them.

There is a strangeness to the cosmic symphony that may encompass time travel, higher dimensions, quantum superspace, and parallel universes—worlds that resemble our own and perhaps even occupy the same space as our own in some ghostly manner. Stephen Hawking has even proposed using wormholes to connect our universe with an infinite number of parallel universes. Edward Witten is working hard on superstring theory, which has already created a sensation in the world of physics because it can explain the nature of both matter and spacetime. By realizing that the fundamental laws of physics appear simpler in higher dimensions, string theory can unite Einstein's theory of gravity with quantum theory in ten dimensions. Our heirs, whatever or whoever they may be, will explore space and time to degrees we cannot currently fathom. They will create new melodies in the music of time. There are infinite harmonies to be explored.

Clifford Pickover is a research staff member at the IBM Thomas J. Watson Research Center. He is the lead writer for Discover Magazine's brain-boggler column and the author of Black Holes: A Traveler's Guide, among many other books. This article was adapted from: Time: A Traveler's Guide, by Clifford A. Pickover. Copyright © 1998 by Clifford Pickover. Used by permission of Oxford University Press, Inc.

Photos: (1) Amanda Clement/Photodisc; (2) Milton Montenegro/Photodisc; (3) Steve Cole/Photodisc; (4) Photodisc Imaging; (5) NASA.

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