THE MIRRORWORLD DOESN’T yet fully exist, but it is coming. Someday soon, every place and thing in the real world—every street, lamppost, building, and room—will have its full-size digital twin in the mirrorworld. For now, only tiny patches of the mirrorworld are visible through AR headsets. Piece by piece, these virtual fragments are being stitched together to form a shared, persistent place that will parallel the real world. The author Jorge Luis Borges imagined a map exactly the same size as the territory it represented. “In time,” Borges wrote, “the Cartographers Guilds struck a Map of the Empire whose size was that of the Empire, and which coincided point for point with it.” We are now building such a 1:1 map of almost unimaginable scope, and this world will become the next great digital platform.

Google Earth has long offered a hint of what this mirrorworld will look like. My friend Daniel Suarez is a best-selling science fiction author. In one sequence of his most recent book, Change Agent, a fugitive escapes along the coast of Malaysia. His descriptions of the roadside eateries and the landscape describe exactly what I had seen when I drove there recently, so I asked him when he’d made the trip. “Oh, I’ve never been to Malaysia,” he smiled sheepishly. “I have a computer with a set of three linked monitors, and I opened up Google Earth. Over several evenings I ‘drove’ along Malaysian highway AH18 in Street View.” Suarez—like Savage—was seeing a crude version of the mirrorworld.

It is already under construction. Deep in the research labs of tech companies around the world, scientists and engineers are racing to construct virtual places that overlay actual places. Crucially, these emerging digital landscapes will feel real; they’ll exhibit what landscape architects call place­ness. The Street View images in Google Maps are just facades, flat images hinged together. But in the mirrorworld, a virtual building will have volume, a virtual chair will exhibit chairness, and a virtual street will have layers of textures, gaps, and intrusions that all convey a sense of “street.”

The mirrorworld—a term first popularized by Yale computer scientist David Gelernter—will reflect not just what something looks like but its context, meaning, and function. We will interact with it, manipulate it, and experience it like we do the real world.