Time

gray of the Moon. But nevertheless Maura sensed there was something wrong. The air seemed chill, and she saw the leaves of the fat, squat oak tree rustle. From somewhere there came an odd cry, perhaps human, perhaps animal.

At the airlock’s inner door was the bulky blond German trooper whom Maura had come to know — and to dislike intensely — during her visits here. He was fingering the revolver at his waist. Anna stood before him, talking earnestly. Her wings were on the ground behind her. There were no other children in sight.

Anna hurried to Maura. “You have to help me. I’m trying to make him understand.”

Maura held Anna’s arms. “What do we have to understand?”

“What is to come.”

Maura’s skin prickled.

Maura glanced at the trooper. He was staring at Anna. Leering, Maura thought uneasily, leering without speaking.

Anna led her away, deeper into the dome across the grass, talking intently. It came out of Anna in broken fragments, scraps of speech. Occasionally the girl would lapse into metalanguage: shards of song, a few clumsy dance steps. “The arrow of time,” she said. “Inner time. Do you understand? This is the key. If you close your eyes you feel time. You feel yourself enduring. Time is essential to awareness, where space is not, and so is more fundamental. The flow of time, events happening, the future coming into existence.”

“Yes.”

“But you don’t understand time. Your scientists use time as a coordinate, a label. You even have theories that are time-symmetric, that work whether you run them forward or back in time.” The girl actually laughed at that.

“And that’s wrong?”

“Of course it’s wrong. It is trivially wrong. There is a severe discrepancy between your theories and what you feel is the reality of the world. And that is telling you, should be telling you, something quite fundamental about the physics that actually underlies your conscious processes.”

“All right. Tell me about the arrow of time.”

Anna danced, whirled, her dress lifting; and Maura was uncomfortably aware of the soldier’s eyes. “There are an infinite number of possible universes in the manifold,” Anna said. “Of those only a subset — nevertheless infinite itself — are capable of supporting self-aware substructures. And those universes are characterized by a flow of time, which is created by unfolding cosmic structure. Gravity is the key.”

Maura was getting lost again. “Gravity?”

“A universe with gravity is driven from smoothness to dumpiness because of gravitational collapse. And the arrow of time comes from this flow of matter and energy, from the gravitational arrangement of the universe at its beginning, to the equilibrium state at its end. Life depends on a flow of energy and information, to be dammed and used. So the arrow of time, like perception itself, is intimately linked to the structure of the universe.”

“Go on.”

Anna was still talking, still dancing. “But structure and change are not restricted to a single universe. They span the manifold of evolving universes. And so, therefore, does life. Do you see?”

“No.”

“When this universe was spawned from the previous generation, it went through a series of phases. That is, the vacuum did.” Anna was watching her, seeking signs of understanding. “The vacuum is a complex thing. Space can be bent by gravity, but it resists with a strength far stronger than steel. The vacuum is a sea of energy, of virtual particles that pop in and out of existence.”

“All right,” Maura said, struggling to keep up.

“But it is possible for the vacuum to take different phases. Think of water. Liquid water may achieve a higher energy phase — it may flash to steam — or it may seek a lower energy phase —”

“By freezing, forming ice.”

“Yes. Systems lose energy, tend to seek the lowest energy state.”

“I understand. And so the vacuum—”

“After the Big Bang the vacuum itself descended through a series of energy states. This is the most primitive unfolding of all, the source of the time river, the source of life and mind.”

“Until it settled on the lowest, umm, energy state. Which is our vacuum. Right?”

Anna frowned. ‘Wo. Our vacuum is only metastable. It is not in the lowest level, not even now. This began in the Big Bang and continues now. But it needs, umm, help.”

“Help? What kind of help?”

The girl grabbed her hands. “You must see what this means. The evolution of the vacuum is a flow of information. But this is a flow that spans the manifold itself, and is therefore fundamental.” Anna’s eyes searched Maura’s. “Life spans the manifold. The vacuum metastability makes you what you are. This is the reason for what we are doing. And this is what you must tell them.”

“Who?”

“The people.” She waved a hand at the soldier, vaguely in the direction of Earth. “Make them understand this.”

“What for?”

“Consolation.”

“My God, Anna—”

And then, it seemed, time ran out for them all.

It was as if a cloud had passed over the sun.

Anna licked a finger and raised her hand. “There’s no breeze,” she said. “They turned the systems off.”

Maura looked up. The dome had darkened. She could see the sun, just, a diffuse distorted disc, shedding no meaningful light. Perhaps the polarization had been switched to its night setting.

Artificial lights sparked, flooding the dome with a cold fluorescent glow, a deadness that contrasted powerfully with the living green warmth of a moment ago.

The German trooper touched Maura’s elbow. She heard the insect whisper of a speaker in his ear. “We have to get you out of here, ma’am.” He was pulling at her, firmly but gently, separating her from Anna; Maura, bewildered, let it happen.

And Maura saw how his fat fingers had wrapped around the girl’s upper arm. Anna wriggled, obviously in pain. But the trooper was holding the girl’s fragile body against his battle dress.

Ugly suspicions coalesced inside Maura; a subplot was reaching its resolution here. “Let her go.”

The trooper grinned. He was tapping at a pad on his chest, perhaps calling for backup. “Ma’am, this is nothing to do with you. The bus will be waiting outside to take you back.”

“I’m not going to let you harm her.”

He just stared at her, holding the girl effortlessly despite her squirming.

Maura braced herself, cupped her hand, and slapped the side of his head as hard as she could.

“Ow… shit, Gott—” He pressed his hand to his damaged ear and let the girl go.

“Run, Anna!”

The girl was already fleeing over the darkened, gray-green grass, toward the center of the dome. Maura saw a giraffe, terrified, loping across the miniature veldt.

“Ma’am.”

She turned. The German was standing before her. His fist drove into her stomach.

The pain slammed into her, doubling her over. She felt as if her intestines had been crushed against her spine, and perhaps they had. She wrapped her arms around her belly and tipped onto the grass, falling with lunar slowness.

But Anna had gotten away.

Now a klaxon started to sound: loud, insistent, a brutal braying, filling the dome with its clamor. Whatever was coming must be close.

She could see the German. He looked after Anna. “Shit, shit,” he said, frustrated.

He walked up to Maura. She saw a flash of leather and combat green. Her right knee exploded in pain, and she howled.

Then he ran off, toward the exit.

Her world was pain now, nothing but that. She was suspended between twin poles of it, at her stomach and her shattered knee, as if a lance had been passed through her body. She was unable to move. She even had to control her own breathing; if she disturbed the position of her body by as much as an inch the pain magnified, never to diminish again.

The klaxon seemed to be growing louder. And lights were pulsing across the dome roof now, great alternating bands of black and white that rushed toward the exits. The light patterns were neat, clean, almost beautiful. Their message was unmistakable, but Maura knew she could not move.

She closed her eyes, longing for the oblivion of unconsciousness. But it didn’t come.

Some Galileo you would have made, Maura.

The light seemed to be fading, even the pain — if not dwindling, then at least growing more remote, diminished by distance.

She looked within and sensed time flowing, as it always had: the blossoming of multiple universes reflected in her own soul. Well, soon the flow of time would stop, for her. How would ilfeelt

But now there was something new. Hands, small hands, at her shoulders and knees and feet and head. She tried to focus her eyes. A face swam before her. Anna’s? She tried to speak, to protest. But she failed.

Then they were lifting her — as children would, clumsily — and her knee erupted in white-hot agony.

She was being carried across the veldt. This was still the Moon, and the low gravity was making it easy for the children to carry her quickly. But even so, every jolt sent new rivers of metallic pain coursing through her leg and belly.

She looked up at the dome. It had turned transparent now, and there was a glaring sun, a blue marble Earth over her.

They came to a glass fence. One section of it had been shattered, and the children hurried through. She was inside the central compound, the forbidden area, where the children’s bubble of spacetime had rested for five years.

And now she was approaching a wall of silver that sparkled, elusive.

She tipped up her head. Something else was in the sky beyond the dome. Beams of light, radiating from a complex, drifting point. The beams were red, blue, yellow, green, rainbow colors, a rotating umbrella. Laser beams? They must already have kicked up debris, she thought: ground their way into Tycho, filled the vacuum with vaporized rock, making the beams themselves visible.

The beams were approaching the dome, rotating like an H. G. Wells Martian tripod.