I loved seeing Gravity. In my opinion, the Planet Earth should be nominated for a supporting-player Oscar. I drank in the massive, stunning views of the earth in the background of so many scenes—completely convincing, thanks to high-level CGI effects. At those screen-filling distances, you could make out the thin, blue-white film of the atmosphere, the delicate outer membrane that makes life on earth possible. There they were: the biosphere and the atmosphere, as seen from space for real by just a few hundred people so far.

That soft shell of atmosphere offers a visual analogue to other, unseen layers, both actual and imagined. There’s cyberspace—a zone of reality that’s tied to physical things like computers, servers, satellites and fiber-optic cable, but can’t be seen or felt. We call this domain digital, but what does that mean? It doesn’t seem farfetched to think of this quickly filling-in worldwide web as another, invisible shell surrounding the earth’s surface.

And then there’s the noosphere, an idea put forward by the theologian Pierre Teilhard de Chardin about 90 years ago. He was inspired by Vladimir Verdansky, a Russian scientist who himself gets credit for coming up with the term “biosphere.” With the noosphere (the prefix comes from Greek nous, for mind) Teilhard invites us into a kind of thought experiment: imagine that all of human thought surrounds the earth in an invisible shell. As our mental outpourings grow and intensify, this “thinking layer” fills in and comes into its own. Teilhard suggested that the noosphere would emerge out of technologies “extending a closely interdependent network” around the world. At that time he was referring to radio, teletype and television—but his description seems to eerily anticipate the Internet and our current web of digital communication.

This promise of the noosphere pulled me in when I first heard about it. It was there when I wrote in the libretto for Violet Fire about Nikola Tesla’s vision of the earth becoming “a single brain” through his planned World Broadcasting System. In Leaving Alexandria, the novel I’m working on, it has helped me envision the accumulation of knowledge, from ancient libraries to our expanding digital cybersphere. We can’t see any of these the way we can see the translucent envelope of our atmosphere, but that doesn’t stop us from experiencing them around us.