It raced back through time in the other direction, and saw that it had left another stroke.

The single quark began to dash back and forth in time, and like the individually meaningless actions of an artist’s pencil, a picture began to emerge.

If it feels to you that we’re connected by a larger whole, you’re mistaken: we’re connected by a smaller particle. Every atom in your body is the same quark in different places at the same moment in time. Our little quark sweeps like a frenetic four-dimensional phosphor gun, painting the world: each leaf on every tree, every coral in the oceans, each car tire, every bird carried on the wind, all the hair on all the heads in the world. Everything you have ever seen is a manifestation of the same quark, racing around on a space-time superhighway of its own invention.

It began to write the story of the world with sagas of war, love, and exile. As it spun out stories and allowed the plots to grow organically, the quark became an increasingly talented storyteller. The stories took on subtle dimensions. Its protagonists engaged in moral complexity; its antagonists were charming. The quark reached for inspiration into its own history of loneliness in an empty cosmos: the adolescent with his head on the pillow, the divorcee staring out the coffee shop window, the retiree watching infomercials—these became the prophets of the quark’s text.

But the quark did not dwell upon the loneliness. It found that it couldn’t get enough of the love stories and the sex scenes. From the complex network of love stories spawned new generations of children, and the storyboard of the space-time canvas became increasingly rich in characters. The quark pursued the logical flow of each story with dedication and integrity.

Then, on an afternoon that would come to be known by our physicists as the Day of Decline, the quark suffered an epiphany. It realized it had reached the limits of its energy. Its stories had grown too baroque and rococo to be contained by the maximum speed of its pencil strokes.

That was the first day the world began drifting toward incompleteness. The quark despondently resigned itself to the fact that it could keep the show going only if it saved energy. It realized it could accomplish this by drawing only those entities that were being observed by someone. Under this conservation program, the great meadows and mountains were only drawn when there was someone there to look. There was nothing drawn under the sea surface where submarines did not travel; there were no jungles where explorers did not probe.

These measures of savings were already in place before you were born. But things are about to get worse. Even with these energy management programs, the quark remains overextended. Given the directionless and explosive growth of the human chronicle, our quark’s reserves are nearing depletion.

Soon, against its will, it will submit to the fact that it cannot continue the narrative. The physicists have advised us to prepare ourselves emotionally for the end of our world: trees will have fewer leaves, both men and women will bald, animals will be drawn with less detail. As the decline continues, you will someday turn a familiar corner to find buildings missing. At some point you may look through the missing walls of your bedroom to find your lover only half drawn.