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I moved my forehead muscles in a way that used to lift my eyebrows. “It looks random to me,” I said. “I mean, it’s not as if the stars are arranged in geometric patterns.”

“There is great beauty in randomness,” said Hollus. “But I speak about a much more basic design. This universe has had its fundamental parameters fine-tuned to an almost infinite degree so that it would support life.”

I was pretty sure I knew where he was going with this, but I said, “In what way?” anyway; I thought maybe he knew something I didn’t — and indeed, to my shock, that was precisely the case.

“Your science knows of four fundamental forces; there are actually five, but you have not yet discovered the fifth. The four forces you know about are gravitation, electromagnetism, the weak nuclear force, and the strong nuclear force; the fifth force is a repulsive one that operates over extremely long distances. The strengths of these forces have wildly varying values, and yet if the values were even slightly different from their current ones, the universe as we know it would not exist, and life could never have formed. Take gravity as an example: were it only somewhat stronger, the universe would have long since collapsed. If it were somewhat weaker, stars and planets never could have coalesced.”

“ ‘Somewhat,’ ” I echoed.

“For those two scenarios, yes; I am talking about a few orders of magnitude. You wish a better example? Very well. Stars, of course, must strike a balance between the gravitational force of their own mass, which tries to make them collapse, and the electromagnetic force of their own outpouring of light and heat. There is only a narrow range of values in which these forces are in sufficient equilibrium to allow a star to exist. At one extreme blue giants are produced, and at the other red dwarfs form — neither of which are conducive to the origin of life. Fortunately, almost all stars fall in between those two types — specifically because of an apparent numerical coincidence in the values of the fundamental constants in nature. If, for instance, the strength of gravity were different by one part in — give me a second; I must convert to your decimal system — by one part in 1040, this numerical coincidence would be disrupted, and every star in the universe would be either a blue giant or a red dwarf; no yellow suns would exist to shine down on Earthlike worlds.”

“Really? Just one part in ten to the fortieth?”

“Yes. Likewise the value of the strong nuclear force, which holds the nucleuses of atoms together even though the positively charged protons try to repel each other: if that force were only slightly weaker than it actually is, atoms would never form — the repulsion of protons would keep them from doing so. And if it were only slightly stronger than it actually is, the only atom that could exist would be hydrogen. Either way, we would have a universe devoid of stars and life and planets.”

“So you’re saying someone chose these values?”

“Exactly.”

“How do you know that these aren’t the only values those constants could possibly have?” I said. “Maybe they are simply that way because they couldn’t possibly be anything else.”

The alien’s round torso bobbed. “An interesting conjecture. But our physicists have proved that other values are indeed theoretically possible. And the odds of the current values arising by chance are one in the number six followed by so many zeros that if you could engrave a zero on each neutron and proton in the entire universe, you could still not write out the number in full.”

I nodded; I’d heard variations on all this before. It was time to play my trump card. “Maybe all the possible values for those constants do exist,” I said, “but in different universes. Maybe there are a limitless number of parallel universes, all of which are devoid of life because their physical parameters don’t allow it. If that’s the case, there’s nothing remarkable about us being in this universe, given that it’s the only one out of all the possible universes that we could be in.”

“Ah,” said Hollus. “I see . . .”

I folded my arms smugly.

“I see,” continued the alien, “the source of your misunderstanding. In the past, the scientists of my world were mostly atheists or agnostics. We have long known of the apparently finely tuned forces that govern our universe; I form the impression that you were already somewhat familiar with them yourself. And that same argument — that there are perhaps an infinite number of universes, manifesting continuums of alternative values for the fundamental constants — was what allowed previous generations of Forhilnor scientists to dismiss the notion of a creator. As you say, if all the possible values exist somewhere, there is nothing noteworthy about the existence of one universe governed by the particular set of values that happens to make life possible.

“But it turns out that there are no long-term parallel universes existing simultaneously with this one; there cannot be. The physicists of my world have attained what those of yours presumably currently seek: a grand unified theory, a theory of everything. I could find little on human beliefs about cosmology in your television and radio, but if you hold the belief you just stated, I will guess that your cosmologists are currently at the stage where they consider a hot, inflationary big-bang model to be the most likely scenario for the origin of the universe. Is that correct?”

“Yes,” I said.

Hollus bobbed. “Forhilnor physicists cherished the same belief — many reputations depended on it — until the fifth interaction, the fifth fundamental force, was discovered; its discovery was related to the energy-production breakthrough that allows us to accelerate ships to within a tiny fraction of lightspeed, despite the relativistic fact that their masses increase enormously as we approach that speed.”

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.