Robert Sawyer - Calculating God

Hollus shifted his weight on his six feet, then continued. “The hot, inflationary big-bang model requires a flat universe — one that is neither open nor closed, one that will essentially last an infinite amount of time; it does, however, allow for parallel universes. But accommodating the fifth force required modification of that theory in order to preserve symmetry; from that modification came the coherent, grand unified theory, a quantum theory that embraces all forces including gravity. That grand unified theory has three important provisions.

“First, that this universe is not flat, but rather that it is closed: it did indeed start with a big bang and will expand for billions of years more — but it will eventually collapse back down to a singularity in a big crunch.

“Second, that this current cycle of creation follows no more than eight previous big-bang/big-crunch oscillations — we are not one in an infinitely long string of universes but, rather, are one of the very few that have ever existed.”

“Really?” I said. I was used to cosmology presenting me with infinities or with values that were precisely one. Eight seemed an unusual number, and I said so.

Hollus flexed his legs at their upper joints. “You introduced me to that man named Chen — your staff astronomer. Talk to him; he will likely tell you that even your hot, inflationary big-bang model, with its requirement for a flat universe, allowed for a very limited number of prior oscillations, if any had occurred at all. I suspect he will consider it quite reasonable to learn that this current iteration of reality is one of only a tiny number of universes that have ever existed.”

Hollus paused, then continued. “And the third provision of the grand unified theory is this: no parallel universes exist simultaneously with ours or any of the previous or subsequent ones, save virtually identical universes with exactly the same physical constants that split briefly from the current one then almost immediately reintegrate with it, thus accounting for certain quantum phenomenons.

“The math to prove all the foregoing is admittedly abstruse, although, ironically, the Wreeds intuitively came to an identical model. But the theory of everything made numerous predictions that have subsequently been confirmed experimentally; it has withstood every test it has been put to. And when we found that we could not retreat into the notion that this universe is one of vast number, the argument for intelligent design became central to Forhilnor thought. Since this is one of a maximum of just nine universes that have ever existed, for it to have these highly improbable design parameters implies they were indeed chosen by an intelligence.”

“Even if maybe, perhaps, the four — excuse me, the five — fundamental forces have seemingly wildly improbable values,” I said, “that still is only five separate coincidences, and, although granted it is hugely unlikely, five coincidences could indeed occur by random chance in just nine iterations.”

Hollus bobbed. “You have intriguing tenacity,” he said. “But it is not just the five forces that have seemingly designed values; many other aspects of the way the universe works appear likewise to have been minutely adjusted.”

“For instance?”

“You and I are made up of heavy elements: carbon, oxygen, nitrogen, potassium, iron, and so on. Practically the only elements that existed when the universe was born were hydrogen and helium, in a roughly three-to-one ratio. But in the nuclear furnaces of stars, hydrogen is fused into heavier elements, producing carbon, oxygen, and so on up the periodic table. All of the heavy elements that make up our bodies were forged in the cores of long-dead stars.”

“I know. ‘We are all star-stuff,’ as Carl Sagan used to say.”

“Precisely. Indeed, scientists from your world and mine refer to us as carbon-based lifeforms. But the fact that carbon is produced by stars depends critically on the resonance states of the carbon nucleus. To produce carbon, two helium nucleuses must stick together until they are struck by a third such nucleus — three helium nucleuses provide six neutrons and six protons, the recipe for carbon. But if the resonance level of carbon were only four percent lower, such intermediate pair-bonding could not occur, and no carbon would be produced, making organic chemistry impossible.” He paused. “But just producing carbon, and other heavy elements, is not enough, of course. Those heavy elements are here on Earth because some fraction of stars — what is the word? When a large star explodes?”

“Supernova,” I said.

“Yes. Those heavy elements are here because some fraction of stars become supernovas, spewing their fusion products into interstellar space.”

“And you’re saying that the fact that stars do go supernova is something that also must have been designed by a god?”

“It is not as simplistic as that.” A pause. “Do you know what would happen to Earth if a nearby star became a supernova?”

“If it were close enough, I suppose we’d be fried.” In the 1970s, Dale Russell had favored a nearby supernova explosion as the cause of the extinctions at the end of the Cretaceous.

“Exactly. If there had been a local supernova anytime in the last few billion years, you would not be here. Indeed, neither of us would be, since our worlds are quite close together.”

“So supernovas can’t be too common, and—”

“Correct. But neither can they be too rare. It is shockwaves made by supernova explosions that cause planetary systems to start to coalesce from the dust clouds surrounding other stars. In other words, if there had been no supernovas ever anywhere near your sun, the ten planets that orbit it would never have formed.”

“Nine,” I said.

“Ten,” repeated Hollus firmly. “Keep looking.” His eyestalks waved. “Do you see the quandry? Some stars must become supernovas in order to make heavy elements available for the formation of life, but if too many do, they would wipe out any life that got started. Yet if not enough do, there would be precious few planetary systems. Just as with the fundamental physical constants and the resonance levels of carbon, the rate of supernova formation again seems precisely chosen, within a very narrow range of possibly acceptable values; any substantial deviation would mean a universe without life or even planets.”

I was struggling for footing, for stability. My head ached. “That could just be a coincidence, too,” I said.

“It is either coincidence piled on top of coincidence,” said Hollus, “or it is deliberate design. And there is more. Take water, for instance. Every lifeform we know of evolved in water, and all of them require it for their biological processes. And although water seems chemically simple — just two hydrogen atoms bound to an oxygen — it is, in fact, an enormously unusual substance. As you know, most compounds contract as they cool and expand as they heat. Water does this, too, until just before it starts to freeze. It then does something remarkable: it begins to expand, even as it grows colder, so that by the time it does freeze, it is actually less dense than it was as a liquid. That is why ice floats instead of sinking, of course. We are so used to seeing that, whether it is ice balls in a beverage or a skin of ice on a pond, that we usually give it no thought. But other substances do not do that: frozen carbon dioxide — what you call dry ice — sinks in liquid carbon dioxide; a lead ingot will sink in a vat of molten lead.

“But water ice floats — and if it did not, life would be impossible. If lakes and oceans froze from the bottom up, instead of the top down, no sea-floor or lake-bottom ecologies would exist outside equatorial zones. Indeed, once they had started freezing, bodies of water would freeze solid and remain solid forever; it is currents moving unfettered beneath surface ice that promotes melting in the spring — that is why glaciers, which have no such currents beneath them, exist for millennia on dry land adjacent to liquid lakes.”