Time for bed.

AFTERWORD

BIG SMART OBJECTS

I. HOW WE BUILT THE BOOKS

Gregory Benford’s take—

In science fiction, a Big Dumb Object is any immense mysterious object that generates an intense sense of wonder just by being there. “The Diamond as Big as the Ritz” by F. Scott Fitzgerald is a non-SF example. They don’t have to be inert constructs, so perhaps the “dumb” aspect also expresses the sensation of being struck dumb by the scale of them.

Larry said to me at a party, “Big dumb objects are so much easier. Collapsed civilizations are so much easier. Yeah, let’s bring them up to speed.”

So we wrote Bowl of Heaven, deciding that we needed two volumes to do justice to a Big Smart Object. The Bowl has to be controlled, because it’s not neutrally stable. His Ringworld is a Big Dumb Object since it’s passively stable, as we are when we stand still. (Or the ringworld would be except for nudges that can make it fall into the sun. Those are fairly easy to catch in time. Larry put active stabilizers into the second Ringworld novel.)

A Smart Object is statically unstable but dynamically stable, as we are when we walk. We fall forward on one leg, then catch ourselves with the other. That takes a lot of fast signal processing and coordination. (We’re the only large animal without a tail that’s mastered this. Two legs are dangerous without a big brain or a stabilizing tail.) There’ve been several Big Dumb Objects in SF, but as far as I know, no smart ones. Our Big Smart Object is larger than Ringworld and is going somewhere, using an entire star as its engine.

Our Bowl is a shell more than a hundred million miles across, held to a star by gravity and some electrodynamic forces. The star produces a long jet of hot gas, which is magnetically confined so well, it spears through a hole at the crown of the cup-shaped shell. This jet propels the entire system forward—literally, a star turned into the engine of a “ship” that is the shell, the Bowl. On the shell’s inner face, a sprawling civilization dwells. The novel’s structure doesn’t resemble Larry’s Ringworld much, because the big problem is dealing with the natives.

The virtues of any Big Object, whether dumb or smart, are energy and space. The collected solar energy is immense, and the living space lies beyond comprehension except in numerical terms. While we were planning this, my friend Freeman Dyson remarked, “I like to use a figure of demerit for habitats, namely the ratio R of total mass to the supply of available energy. The bigger R is, the poorer the habitat. If we calculate R for the Earth, using total incident sunlight as the available energy, the result is about twelve thousand tons per watt. If we calculate R for a cometary object with optical concentrators, traveling anywhere in the galaxy where a zero magnitude star is visible, the result is one hundred tons per watt. A cometary object, almost anywhere in the galaxy, is 120 times better than planet Earth as a home for life. The basic problem with planets is that they have too little area and too much mass. Life needs area, not only to collect incident energy but also to dispose of waste heat. In the long run, life will spread to the places where mass can be used most efficiently, far away from planets, to comet clouds or to dust clouds not too far from a friendly star. If the friendly star happens to be our Sun, we have a chance to detect any wandering life-form that may have settled here.”

This insight helped me think through the Bowl, which has an R of about 10−10! The local centrifugal gravity avoids entirely the piling up of mass to get a grip on objects, and just uses rotary mechanics. So of course, that shifts the engineering problem to the Bowl’s structural demands.

Big human-built objects, whether pyramids, cathedrals, or skyscrapers, can always be criticized as criminal wastes of a civilization’s resources, particularly when they seem tacky or tasteless. But not if they extend living spaces and semi-natural habitat. This idea goes back to Olaf Stapledon’s Star Maker:

Not only was every solar system now surrounded by a gauze of light traps, which focused the escaping solar energy for intelligent use, so that the whole galaxy was dimmed, but many stars that were not suited to be suns were disintegrated, and rifled of their prodigious stores of sub-atomic energy.

Our smart Bowl craft is also going somewhere, not just sitting around, waiting for visitors like Ringworld—and its tenders live aboard.

We started with the obvious: Where are they going, and why?

Answering that question generated the entire frame of the two novels. That’s the fun of smart objects—they don’t just awe, they also intrigue.

My grandfather used to say, as we headed out into the Gulf of Mexico on a shrimping run, A boat is just looking for a place to sink.

So heading out to design a new, shiny Big Smart Object, I said, An artificial world is just looking for a seam to pop.

You’re living just meters away from a high vacuum that’s moving fast, because of the Bowl’s spin (to supply centrifugal gravity). That makes it easy to launch ships, since they have the rotational velocity with respect to the Bowl or Ringworld … but that also means high seam-popping stresses have to be compensated. Living creatures on the sunny side will want to tinker, try new things.…

“Y’know, Fred, I think I can fix this plumbing problem with just a drill-through right here. Uh—oops!”

The vacuum can suck you right through. Suddenly you’re moving off on a tangent at a thousand kilometers a second—far larger than the 50 km/sec needed to escape the star. This makes exploring passing nearby stars on flyby missions easy.

But that easy exit is a hazard, indeed. To live on a Big Smart Object, you’d better be pretty smart yourself.

Larry Niven’s take—

“The Enormous Big Thing” was my friend David Gerrold’s description of a plotline that flowered after the publication of Ringworld. Stories like Orbitsville, Ring, Newton’s Wake, John Varley’s Titan trilogy and Rendezvous with Rama depend on the sense of wonder evoked by huge, ambitious endeavors. Ringworld wasn’t the first; there had been stories that built, and destroyed, whole universes. These objects often become icons of larger issues implying unknowable reaches and perspectives. Their governing question is usually, “Who built this thing? And why?” They had fallen out of favor.

I wasn’t the first to notice that a fallen civilization is easier to describe than a working one. Your characters can sort through the artifacts without hindrance until they’ve built a picture of the whole vast structure. Conan the Barbarian, and countless barbarians to follow, found fallen civilizations everywhere. I took this route quite deliberately with Ringworld. I was young and untrained, and I knew it.

A fully working civilization, doomed if they ever lose their grasp on their tools, is quite another thing. I wouldn’t have tried it alone. Jerry Pournelle and I have described working civilizations several times, in Footfall, Lucifer’s Hammer, and The Burning City.

With Greg Benford, I was willing to take a whack at a Dyson-level civilization. Greg shaped the Bowl in its first design. It had a gaudy simplicity that grabbed me from the start. It was easy to work with: essentially a Ringworld with a lid, and a star for a motor. We got Don Davis involved in working some dynamite paintings.

Greg kept seeing implications. The Bowl’s history grew more and more elaborate. Ultimately I knew we’d need at least two volumes to cover everything we’d need to show. That gave us time and room.