Alan Lightman wrote a book in 1996 entitled “Einstein’s Dreams.” Einstein was famous for his facility with hypotheticals, and solved some of physics’ hardest problems by spinning yards and yards of thought experiments. He had enlarged parietal lobes, apparently.

“Einstein’s Dreams” is a fictional exploration of what those experiments might’ve been, as Einstein toiled away in a patent office, dreaming up relativity. It tastes like Calvino. In one world, time passes more slowly farther from the earth’s center. In an attempt to “live longer,” in this world all the rich build their homes, shops and gymnasiums on stilts. The poor sow their seeds in the forgotten soil and frolic in the abandoned brooks and rivers. In another world, time passes more slowly for something the faster it moves through space. This chapter is buried in the middle and full of preternaturally powered automobiles.

Finally, in a third world, time is merely stretched. Or man’s experience of it is compressed. It takes a literal lifetime for the earth to complete a full rotation. People age as we do—process the world and each other at the same rate as us—but we only see one day, as opposed to 25,000. Born at sunrise, you’re middle-aged at sunset, depending on the season. It is a terrifying environment.

In this world, each individual has to witness a grand transformation. Whether born in night or daytime, someday the world suddenly, definitively (though not without warning), becomes a completely foreign place.

This world can be interpreted as our own, as I’m afraid they are all meant to be. Because this happens. Over the course of a life the world mutates beyond recognition. You go about your life minding your own business and then—wouldn’t you know it—time is no longer absolute. Electricity is magnetism. The earth is round.

Please appreciate the delta caused by the discoveries. So much happens! Imagine living to see horse-drawn carriages replaced by automobiles. It only took a few decades. If you’re in your 20s in the trenches, you’re in your 50s when they drop the bomb, and you’ve still got ‘Nam, psychedelia and the flower people ahead of you. Imagine growing up in a world of high necklines, where the phonograph was a novelty, as was jazz, and ending up in a world of Elvis and broadcast television. No wonder they were so ornery.

The idea of the event horizon is borrowed from physics. It describes the line of proximity to a black hole, beyond which events (and light) cannot affect an outside observer.

“Einstein’s Dreams” is about the different worlds beyond the different possible answers to the problem of relativity. How ideas shape history. Our narrator is pessimistic for the individuals who get lost in the flow of time: “When the sunrise comes,” he says, “those born at sunset are overwhelmed by the sudden sight of trees and oceans and mountains, are blinded by daylight, return to their houses and cover their windows, spend the rest of their lives in half light.”

But we’ve already crossed one event horizon in our lifetimes. We were young, sure, but still, we made it! Remember before the Internet? Remember before the household PC? The laptop? The cell phone? The smartphone? People our age were keeping paper address books and using landlines less than a decade ago. Somehow we went, in my own personal memory, from nobody in the U.S. suburbs having a cell phone to every Calcutta rickshaw walla carrying one in his dust-saturated shirt.

And just think of all the software that’s changed our lives. Life (or research) before Google? Nobody reads the whole book anymore! They just sample a few pages and slap it in their thesis paper (for which, if it’s vetted enough, someone else will likely do the same). And Facebook was merely budding four years ago.

I’m not saying each of these technological and cultural advances constituted an “event horizon” in and of itself. But I am saying the world is a radically different place than it was 10 years ago, and while we were young and supple then, adaptive now, there’s certainly more to come. Computational genetics and artificial intelligence are ticking time bombs of the future. There are a couple big paradigmatic problems, and once we’ve moved past them, who knows? (People making machines making machines making people. Maybe. That’ll be interesting.)

It’s unclear whether we are doomed to hiding in the dark. Some seem to think we’ll be able to keep up. This may just be naiveté, but I’m somewhat convinced when people say the cultural/technological rate of change seems to be increasing. Lightman’s days are getting shorter before our eyes, to the point that we’re almost used to it. Hence the hope for a psychically comfortable future. But I don’t think we’d ever get off that easy. If we’ve adapted to constantly adapting, that can change, too: a shift abstracted up a level. Whether darkness or light lies beyond the horizon, we’ll just have to wait and see.

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