Ice-Born came towards her, hesitantly. "We're concerned about you."

"Then don't be," she snapped. "Go back to the Chimney, and leave me here."

"No," Strong-Flukes said quietly.

Cilia-of-Gold felt desperate, angry, confined. "You know what's wrong with me, Strong-Flukes. I have a Seeker. It's going to kill me. And there's nothing any of us can do about it."

Their bodies pressed close around her now; she longed to open up her carapace to them and bury herself in their warmth.

"We know we're going to lose you, Cilia-of-Gold," Ice-Born said. It sounded as if she could barely speak. Ice-Born had always been the softest, the most loving, of the Three, Cilia-of-Gold thought, the warm heart of their relationship. "And--"

"Yes?"

Strong-Flukes opened her carapace wide. "We want to be Three again," she said.

Already, Cilia-of-Gold saw with a surge of love and excitement, Strong-Flukes's ovipositor was distended: swollen with one of the three isogametes which would fuse to form a new child, their fourth...

A child Cilia-of-Gold could never see growing to consciousness.

"No!" Her cilia pulsed with the single, agonized word.

Suddenly the warmth of her Three-mates was confining, claustrophobic. She had to get away from this prison of flesh; her mind was filled with visions of the coolness and purity of Ice: of clean, high Ice.

"Cilia-of-Gold. Wait. Please--"

She flung herself away, along the wall. She came to a tunnel mouth, and she plunged into it, relishing the tunnel's cold, stagnant water.

"Cilia-of-Gold! Cilia-of-Gold!"

She hurled her body through the web of tunnels, carelessly colliding with walls of Ice so hard that she could feel her carapace splinter. On and on she swam, until the voices of her Three-mates were lost forever.

We've dug out a large part of the artifact, Irina, Dolores Wu reported. It's a mass of what looks like hull material.

"Did you get a sample?"

No. We don't have anything that could cut through material so dense... Irina, we're looking at something beyond our understanding.

Larionova sighed. "Just tell me, Dolores," she told Wu's data-desk image.

Irina, we think we're dealing with the Pauli Principle.

Pauli's Exclusion Principle stated that no two fermions -- electrons or quarks -- could exist in the same quantum state. Only a certain number of electrons, for example, could share a given energy level in an atom. Adding more electrons caused complex shells of charge to build up around the atom's nucleus. It was the electron shells -- this consequence of Pauli -- that gave the atom its chemical properties.

But the Pauli Principle didn't apply to photons; it was possible for many photons to share the same quantum state. That was the essence of the laser: billions of photons, coherent, sharing the same quantum properties.

Irina, Wu said slowly, what would happen if you could turn off the Exclusion Principle, for a piece of fermionic matter?

"You can't," Larionova said immediately.

Of course not. Try to imagine anyway.

Larionova frowned. What if one could lase mass? "The atomic electron shells would implode, of course."