"But how can that be all of Universal AC?" Zee Prime had asked.
"Most of it," had been the answer, "is in hyperspace. In what form it is there I cannot imagine."
Nor could anyone, for the day had long since passed, Zee Prime knew, when any man had any part of the making of a Universal AC. Each Universal AC designed and constructed its successor. Each, during its existence of a million years or more accumulated the necessary data to build a better and more intricate, more capable successor in which its own store of data and individuality would be submerged.
The Universal AC interrupted Zee Prime's wandering thoughts, not with, words, but with guidance. Zee Prime's mentality was guided into the dim sea of Galaxies and one in particular enlarged into stars.
A thought came, infinitely distant, but infinitely clear. "this is the original galaxy of man."
But it was the same after all, the same as any other, and Zee Prime stifled his disappointment.
Dee Sub Wun, whose mind had accompanied the other, said suddenly, "And is one of these stars the original star of Man?" The Universal AC said, "man's original star has gone nova. it is a white dwarf."
"Did the men upon it die?" asked Zee Prime, startled and without thinking.
The Universal AC said, "a new world, as in such cases, was constructed for their physical bodies in time."
"Yes, of course," said Zee Prime, but a sense of loss overwhelmed him even so. His mind released its hold on the original Galaxy of Man, let it spring back and lose itself among the blurred pin points. He never wanted to see it again.
Dee Sub Wun said, "What is wrong?"
"The stars are dying. The original star is dead."
"They must all die. Why not?"
"But when all energy is gone, our bodies will finally die, and you and I with them."
"It will take billions of years."
"I do not wish it to happen even after billions of years. Universal AC! How may stars be kept from dying?"
Dee Sub Wun said in amusement, "You're asking how entropy might be reversed in direction."
And the Universal AC answered: "there is as yet insufficient data for a meaningful answer."
Zee Prime's thoughts fled back to his own Galaxy. He gave no further thought to Dee Sub Wun, whose body might be waiting on a Galaxy a trillion light-years away, or on the star next to Zee Prime's own. It didn't matter.
Unhappily, Zee Prime began collecting interstellar hydrogen out of which to build a small star of his own. If the stars must someday die, at least some could yet be built.
Man considered with himself, for in a way, Man, mentally, was one. He consisted of a trillion, trillion, trillion ageless bodies, each in its place, each resting quiet and incorruptible, each cared for by perfect automatons, equally incorruptible, while the minds of all the bodies freely melted one into the other, indistinguishable.
Man said, "The Universe is dying."
Man looked about at the dimming Galaxies. The giant stars, spendthrifts, were gone long ago, back in the dimmest of the dim far past. Almost all stars were white dwarfs, fading to the end.
New stars had been built of the dust between the stars, some by natural processes, some by Man himself, and those were going, too. White dwarfs might yet be crashed together and of the mighty forces so released, new stars built, but only one star for every thousand white dwarfs destroyed, and those would come to an end, too.
Man said, "Carefully husbanded, as directed by the Cosmic AC, the energy that is even yet left in all the Universe will last for billions of years."
"But even so," said Man, "eventually it will all come to an end. However it may be husbanded, however stretched out, the energy once expended is gone and cannot be restored. Entropy must increase forever to the maximum."
Man said, "Can entropy not be reversed? Let us ask the Cosmic AC."
The Cosmic AC surrounded them but not in space. Not a fragment of it was in space. It was in hyperspace and made of something that was neither matter nor energy. The question of its size and nature no longer had meaning in any terms that Man could comprehend.
"Cosmic AC," said Man, "how may entropy be reversed?"
The Cosmic AC said, "there is as yet insufficient data for a meaningful answer."
Man said, "Collect additional data."
The Cosmic AC said, "i will do so. i have been doing so for a hundred billion years. my predecessors and i have been asked this question many times. all the data i have remains insufficient."
"Will there come a time," said Man, "when data will be sufficient or is the problem insoluble in all conceivable circumstances?"
The Cosmic AC said, "no problem is insoluble in all conceivable circumstances."
Man said, "When will you have enough data to answer the question?"
The Cosmic AC said, "there is as yet insufficient data for a meaningful answer."
"Will you keep working on it?" asked Man.
The Cosmic AC said, "i will."
Man said, "We shall wait."
The stars and Galaxies died and snuffed out, and space grew black after ten trillion years of running down.
One by one Man fused with AC, each physical body losing its mental identity in a manner that was somehow not a loss but a gain.
Man's last mind paused before fusion, looking over a space that included nothing but the dregs of one last dark star and nothing besides but incredibly thin matter, agitated randomly by the tag ends of heat wearing out, asymptotically, to the absolute zero.
Man said, "AC, is this the end? Can this chaos not be reversed into the Universe once more? Can that not be done?"