The ballooning bubble wasn’t a perfect sphere, Malenfant saw absently. It was becoming blistered, growing irregularly, as if diseased. Its surface glowed pink-white and it was speckled, as if illuminated by laser light. The stars seemed to be shifting around the swelling edge, their position sliding, turning briefly to arcs of light before the shell obscured them — gravitational lensing, perhaps, as the shell distorted spacetime itself.

…Earth gone, just like that, in a fraction of a second, as if it were no more substantial than a match stalk caught in a firestorm. Earth, all of its billions of years of geology and life, core and mantle and oceans and drifting continents, evolution and climate: all of it gone, as if it never existed, its story over.

And the people. Billions dead, their stories summarily ended. The species already extinct, unless anybody had managed to get away to the outer planets, the stars.

He felt numb, unable to believe it. Shouldn’t he have felt it, the brief cries of those billions of souls, caught in the middle of their lives, arguing or laughing or crying, giving birth or dying, making love or war?

Michael was watching him, as if trying to gauge his reaction. They would have seen nothing. An instant of glowing sky, a moment of pain —

“Michael, what’s inside the bubble? What happened to Earth when it passed the barrier?”

Different physical laws. Anything of our universe that survived the unreality pulse itself would immediately decay into new forms. Physics, chemistry as we know it could not proceed.

But even this new regime, the regime of changed matter, would not persist. The energy density in there is intense, the gravity field it generates very strong. In microseconds after the nucleation — even before the bubble expanded beyond the Moon itself, when the bubble was only a mile across — a gravitational collapse started.

“Like a Big Crunch.”

Yes. But none of the slow collapse and compression you witnessed in the precursor universes, Malenfant. Immediate. This is the true vacuum, Malenfant, the final state of the universe. . .

When the universe was born, erupting out of its Big Bang, it went through a series of phase changes, the vacuum collapsing to new, more stable forms. And with each change, with the decay of each false vacuum, energy was released. Those monstrous energy pulses fueled the initial expansion of the universe.

At last the phase changes ceased, and the universe stabilized.

But the stability it reached was false.

I was told a story of a princess who is imprisoned on top of a perfect crystal sphere. There are no iron bars to hold her there, yet she is trapped at the sphere’s highest point. As long as she stays there, at the point of maximum symmetry, she is safe. But if she steps aside in any direction, she will slip and fall. So it is with the universe. Maximum symmetry is unstable.

“But now the children have disturbed that symmetry.”

Yes. Their high-energy event allowed quantum tunneling to a state of true vacuum … Ah. There was a burst of light on the edge of the expanding bubble. Venus, I think…

The unreality wall approached the sun. The bubble was now sixteen light-minutes across, two hundred million miles wide, dwarfing the sun. But the star seemed unperturbed, even as the great hull raced toward it.

Light speed, Malenfant, Michael whispered. If you were standing on the surface of the sun, you would still see stars and Earth and Moon, the last photons reflected by the planet before its destruction. The wall arrives with the light itself. . .

The wall blew across the sun, a tornado engulfing a brightly lit farmhouse. But the sun, a million miles across, was no mere mote of rock and water and life, like Earth. The wall took three, four, five seconds to overwhelm the sun’s glowing mass. Right to the end the surviving sector of the sun kept its spherical shape, kept shining, emitting photons generated by a fusion core that had vanished into unreality seconds before.

Still, it took just heartbeats.

When the sun was gone it grew darker. A final nightfall, Malenfant thought.

And now there was only the sphere of unreality, growing ferociously and unevenly, sparkling, clumpy blisters bursting from its sides, stars curdling around its edge. Soon, he realized, it would become a wall, blanketing the universe.

There will be little to see for a while, Michael said. It will sweep across Mars, the asteroid belt.

“Cruithne?”

Gone already. Then, in half an hour, it will reach us.

The bubble continued to swell visibly, its light glaring.

“It’s never going to stop,” Malenfant whispered. “It will consume the Solar System, the stars—”

This isn ‘t some local phenomenon, Malenfant. This is a fundamental change in the structure of the universe. It will never stop. It will sweep on, growing at light speed, a runaway feedback fueled by the collapse of the vacuum itself. The Galaxy will be gone in a hundred thousand years, Andromeda, the nearest large galaxy, in a couple of million years. It will take time, but eventually —

“The future has gone,” Malenfant said. “My God. That’s what this means, isn’t it? The downstream can’t happen now. All of it is gone. The colonization of the Galaxy; the settlement of the universe; the long, patient fight against entropy…” That immense future had been cut off to die, like a tree chopped through at the root. “Why, Michael? Why have the children done this? Burned the house down, destroyed the future—”

Because it was the wrongfuture. Michael looked around the sky. He pointed to the lumpy, spreading edge of the unreality bubble. There. Can you see that? It’s already starting…

“What is?”

The budding. . . The growth of the true vacuum region is not even. There will be pockets of the false vacuum — remnants of our universe — isolated by the spreading true vacuum. The fragments of false vacuum will collapse. Like—

“Like black holes.” And in that instant, Malenfant understood. “That’s what this is for. This is just a better way of making black holes, and budding off new universes. Better than stars, even.”

Much better. Much. The black holes created as the vacuum decay proceeds will overwhelm by many orders of magnitude the mere billion billion that our universe might have created through its stars and galaxy cores.

“And the long, slow evolution of the universes, the branching tree of cosmoses?…”

We have changed everything, Malenfant. Mind has assumed responsibility for the evolution of the cosmos. There will be many daughter universes — universes too many to count, universes exotic beyond our imagining — and many, many of them will harbor life and mind.

“But we were the first.”

Now he understood. This was the purpose. Not the long survival of humankind into a dismal future of decay and shadows, the final retreat into the lossless substrate, where nothing ever changed or grew. The purpose of humankind — the first intelligence of all — had been to reshape the universe in order to bud others and create a storm of mind.

We got it wrong, he thought. By striving for a meaningless eternity, humans denied true infinity. But we reached back, back in time, back to the far upstream, and spoke to our last children — the maligned Blues — and we put it right.

This is what it meant to be alone in the universe, to be the first. We had all of infinite time and space in our hands. We had ultimate responsibility. And we discharged it.

We were parents of the universe, not its children.

Michael said softly, Isn’t this why you came to Cruithne, Malenfant? To discover purpose? And you had a role to play.