“How long ago?”

“Time is nested…”

From this vantage, the era of man’s first black hole empire had been the spring time, impossibly remote. And the Afterglow itself — the star-burning dawn — was lost, a mere detail of the Big Bang.

“What is happening here, Geador?”

“There is no time — ”

“Tell me.”

The universe had ballooned, fueled by time, and its physical processes had proceeded relentlessly.

Just as each galaxy’s stars had dissipated, leaving a rump that had collapsed into a central black hole, so clusters of galaxies had broken up, and the remnants fell inward to cluster-scale holes. And the clusters in turn collapsed into supercluster-scale holes — the largest black holes to have formed naturally, with masses of a hundred trillion stars.

These were the cold hearths around which mankind now huddled.

“But,” said Geador, “the supercluster holes are evaporating away — dissipating in a quantum whisper, like all black holes. The smallest holes, of stellar mass, vanished when the universe was a fraction of its present age. Now the largest natural holes, of supercluster mass, are close to exhaustion as well. And so we must farm them.

“Look at the City.” He meant the universe-spanning net, the rippling surfaces within.

The City was a netted sphere. It contained giant black holes, galactic supercluster mass and above. They had been deliberately assembled. And they were merging, in a hierarchy of more and more massive holes. Life could subsist on the struts of the City, feeding off the last trickle of free energy.

Mankind was moving supercluster black holes, coalescing them in hierarchies all over the reachable universe, seeking to extend their lifetimes. It was a great challenge.

Too great.

Sombrely, Geador showed her more.

The network was disrupted. It looked as if some immense object had punched out from the inside, ripping and twisting the struts. The tips of the broken struts were glowing a little brighter than the rest of the network, as if burning. Beyond the damaged network she could see the giant coalescing holes, their horizons distorted, great frozen waves of infalling matter visible in their cold surfaces.