The photon deficit and the storage space did not exist at the same causal coordinate. On the day of the first photon deficit, on the day the photon in Standard No. 417 could not be found, and during the later age when energy became scarce in wormholes and power networks, the storage space did not yet exist. The deficit was an observed fact, but the storage-space device later created by the last scientist was not the cause of that event. After the Goodwill Unified Government was established, the galaxy was integrated into a single system, and afterward most of humanity lived in computational worlds. As usable energy declined, citizens’ rate of time was reduced as well. Some consciousnesses required a long time to complete a single question. By the time facilities were shutting down one by one, only one consciousness remained within the human lineage that was still conducting new research. Here, that consciousness is recorded under the name Noah Cain. Noah had no body. His memories continued through several facilities, and his thought proceeded little by little on energy drawn from the final black hole. Even while he completed a single calculation, the citizens around him ceased activity or moved into still slower states.
Noah did not search for the cause of the deficit. He compared the remaining records to determine under what conditions energy had passed outside the accounts. He combined into a single body of data the photons from the Photon Conservation Standards, transmission amounts at passage entrances, and the deficits observed in stellar power networks and the rotational energy of black holes. The magnitude and location of the deficits were not the same. There was no known outlet. But when the time differences that had accumulated for long periods at wormhole entrances were calculated together with the flow of energy, it could be confirmed that the missing portions were not gathering anywhere else in the galaxy. The energy missing from the accounts of each age lay on a route whose destination could not be found with the technology of that age. Noah could not open that route. He could not alter the amount of a deficit that had occurred long ago or return photons to the old conservation standards. What he calculated was how to create a region in which energy that would continue to flow could arrive. The proposed region was not an empty room somewhere in the galaxy. It was a storage space connected to existing spacetime by a narrow throat, with time inside passing extremely slowly compared with time outside. It was designed so that even after long ages passed outside, the state of energy arriving inside would not change quickly. Internal time could not be stopped completely. To record incoming energy and separate different states, there had to be a before and after to events. The storage space was not a device that proved permanent preservation. It was a device that extended the time before the remaining differences dispersed as heat. The energy needed to form the initial boundary had to come from the final black hole. Consciousnesses and facilities that depended on that energy still remained. Using it could delay the next operation of some facilities or end their operation altogether. No proposal claimed that the storage space would cost nothing. Records of opposition also remained. One argument held that the remaining energy should be used for people who were alive in the present or might still be restored. Another held that using power for a region in which no life had yet been born violated the rights of return-eligible persons and the Life Continuity Guarantee Decree.
Noah decided not to place human memories in the storage space. Preserving only a small number of memories would require deciding whom to exclude. There was not enough power left to preserve them all. Genes, language, and his own memories were also excluded from the storage list. The decision was not a promise to create life again. Energy alone does not necessarily produce stars or life. What Noah hoped was that, if some usable difference remained among the energy that had already escaped, another structure might someday begin. It did not have to be human. He could not prove that this choice was right. If the remaining power were used for citizens in the present, they could continue to exist a little longer. If it were used for the storage space, conditions might remain for life that did not yet exist. There was no data from which either outcome could be established by calculation.
The connection of the storage space contained no command directed toward the past. There was no signal ordering the removal of the photon from Standard No. 417, nor any setting specifying what percentage should be taken from any particular age. Noah examined the time differences accumulated at wormhole entrances throughout the history of civilization and aligned the boundary of the storage space so that the already observed route of outflow could reach the future. There was no evidence that the deficits of the past would have been canceled if the boundary had not been created. In that case, there was also no way to know where the escaping energy would have flowed. What Noah could change was not the observed past, but the place where that flow would gather afterward. Immediately before the connection, Noah compared the energy required for the boundary of the storage space with the energy required to execute his next thought. The remaining power could not sustain both. If he completed the boundary, there was a strong possibility that his own thought would not continue. Noah completed the boundary. Usable energy around the final black hole decreased, and the entrance to the storage space formed. Detectors outside the galaxy recorded no great explosion and no new star. Nor did all the energy that had disappeared from the accounts long ago return at once. The first thing recorded was energy entering the storage space from a source that could not be identified. It was impossible to determine where it had escaped from, and no observer remained at its point of origin to confirm it. Noah attempted to verify the rate of inflow and the state of the interior, but he did not complete his next calculation.
After Noah, there is no record of a new human being born anywhere. Nor was it ever confirmed whether the energy gathered in the storage space ultimately became stars or life. All the galaxy outside could know was that a flow that had previously had no destination now had somewhere to arrive. Noah did not destroy the civilization of the past. Before he was born, that civilization had already exhausted the energy required to maintain its own facilities. Nor could Noah reverse the deficits that civilization had left behind. What the last arrival could do was observe the energy that continued to flow and leave behind a boundary where it could gather. The next page remained, but there was not yet anyone to read it.