n Star Trek, Star Wars and dozens of other science-fiction series, faster-than-light messages are routinely sent across the galaxy by starships that are themselves moving faster than light. Leaving aside the question of whether this is possible, such instant messaging does raise serious problems, because according to Einstein's theory of relativity there's no such thing as an "instant" at all. Time and space are twisted together; nothing is ever truly simultaneous.
In fact, even the rules of cause and effect can go astray in Einstein's universe; from the bridge of my starship I may see Event A leading up to Event B, while you, from the bridge of a different ship, moving in a different direction, may see the two events happen in exactly the opposite order. This is true even if we're moving at sublight speed, but if we somehow manage to push our ships into warp it gets even worse, because it may be possible to send messages backward in time. The "now" that I perceive may be completely different from yours, and may never occur at all in your frame of reference.
On the atomic scale where nanotechnology operates, the situation is even more diffuse, because quantum mechanics has demolished the concept of a unique past or a definite future. With rules like Heisenberg's Uncertainty Principle in effect, not only do "here" and "now" become fuzzy concepts at best, but time itself seems to slip from our grasp, to defy any rigorous analysis. The present emerges from an infinity of possible histories, and vanishes into an equal infinity of possible futures. Up close time is a total mess; it makes sense only when we step back to view it from a distance. Confusing? Not really, because our own human perceptions, mushy and skewed as they are, fit very nicely into this framework.
Let me back up for a minute.
The future is ... when?
William Gibson is famous for saying, "The future has arrived, it's just not evenly distributed." In other words, most of the scientific, technological and social changes that will mark the coming decades already exist, in university and corporate laboratories, in the cars and homes of the wealthy, in bellwether neighborhoods where new trends catch on early and sink deep roots. The "now" that you perceive is completely different from the now that a cutting-edge scientist sees, or an architect, or even a plumber. It may be five years before the guts of your toilet need replacing, and I'm betting the new equipment will look quite different from the junk that's in there now. But your plumber has seen it already; he's living in your future.
In fact, Gibson's comment is a counterpoint to one made 50 years earlier by William Faulkner: "The past is never dead. It isn't even past." Events that happened in living memory will always seem recent to someone, and even the ones that happened long ago, before any of us were born, have left their enduring imprint on the physical and cultural landscape. Did the Roman Empire vanish in 455 A.D., when the Visigoth hordes sacked the city for 14 brutal days? Before you answer that, hold a Roman coin in your hand sometime—they're still quite common—or tour the Coliseum while listening to the writings of the Stoics on your MP3 player. In fact, Rome is all around us, all the time.
These observations are of sudden interest to me, because I've just returned from my 20-year high school reunion, that great American ritual where the mingling of past, present and future is especially, poignantly visible. The children have become parents, the mousy have become confident and the creases of old age are clearly written in the lines of our faces at midlife. And yet everyone is pretty much the same as ever—still 18 on the inside, and eagerly wondering what the future has in store.
Cut loose from the web of time
Now, before you start thinking I've gone maudlin and mopey, I should mention that my high school experience was probably quite different than yours. As a teenager, I lived in a hidden valley just south of the Air Force Academy in Colorado Springs, and went to Air Academy High School right there on the base. Ours was an idiosyncratic student body: affluent and educated but also rural and very conservative. Our fashions and mores owed as much to the 1950s as the 1980s; drugs and funny hair were almost unknown, and we could ride our horses and shoot our guns right there in our own five-acre yards, or the 50-acre fields and forests behind them.
And yet, between the Academy facilities and the nearby Digital Equipment Corporation, we had access to some of the hottest computer technology of the day. Years before the Apple II Plus and TRS-80 had pushed their way into millions of American homes, we were writing our own games and accounting programs, and conversing on the early equivalent of chat rooms and newsgroups, email listservs and instant messengers. So while my legal childhood may have ended in September of 1984, in a very real sense I spent my teenage years in both the mid-'90s and the mid-'50s.
Before that, oddly enough, I lived for eight years in a suburb of Boston that, though I didn't know it at the time, was largely a historic restoration set up by Henry Ford in the 1920s. My house, surrounded by stone walls dating back to colonial times, stood within easy walking distance of a 200-year-old church, a 300-year-old inn and the little red schoolhouse where a girl named Mary once brought a little lamb. And a few minutes farther on were a penny candy store, a flea circus and the oldest continuously operating grist mill in North America. Only when we moved away did I learn that most people's flour didn't have little ground-up bits of millstone in it. This was as much Mark Twain's America as Gerald Ford's. But there were also Pong and disco music, Star Wars and Mad magazine. And at the YMCA summer camp my parents always sent me to, the counselors had not yet relinquished the late '60s, and dwelt in a kind of perpetual Summer of Love.
My favorite author was H.G. Wells (1866-1946), my favorite TV show was Leave It to Beaver (1957-1963), and the important thing to consider in all this is that my childhood, while unique, was not unusual. Neither was yours; neither is anyone's. We all grow up in a dozen different eras, surrounded by antiques and ephemera, living treasures and little anomalous bits of future. Einstein and Heisenberg were exactly right: There's no such thing as now. There never has been. Even Mark Twain lived in a jumble of his own past and future, and so will our own grandchildren, and theirs.
Now, this is supposed to be a science column, so I'll turn this philosophizing in a more practical direction. How do we apply it? The glib answer would be something like "Never buy anything made of particle board" or "Take good notes—you're about to forget this." If the future is here already, then our mistakes and oversights, half-measures and under-rug sweepings will come back to haunt us sooner rather than later. Indeed, maybe they already have, and we just don't know it yet.
But in a fictional sense, there's a deeper lesson: Everything persists. Even 200 years in the future—even 2,000 years—the echoes of today should be clearly visible. Not dominant, perhaps, but lurking in the background. And should we travel back to ancient Rome, we'd no doubt find a hundred shocking things that haven't changed a bit. Hamburgers! Sports teams! Honeyed apples on a stick!
If history were a book and each moment were a page, then the flip-flip-flipping of time really would bury the past. But I think time is more like the World Wide Web; too huge to grasp, too fleeting to catalog, always changing and yet always bowing to the same eternal needs and forces. The dollar! The libido! The pursuit of a good meal and a hearty laugh! Some structures change daily, others not at all, and in between there are wonders aplenty. So, to mix a bad metaphor, my friends ... with the world as our keyboard and science fiction as our browser, I suggest we hit the surf.
Sources used for writing this column can be found here.
Wil McCarthy is a rocket guidance engineer, robot designer, nanotechnologist, science-fiction author and occasional aquanaut. He has contributed to three interplanetary spacecraft, five communication and weather satellites, a line of landmine-clearing robots and some other "really cool stuff" he can't tell us about. His short writings have graced the pages of Analog, Asimov's, Wired, Nature and other major publications, and his book-length works include the New York Times notable Bloom, Amazon "Best of Y2K" The Collapsium and most recently Lost in Transmission. His acclaimed nonfiction book, Hacking Matter, is now available in paperback.
