Theyd already had considerable success with their quantum computer. Last tenmonth, they had factored a number that required 10^73 hydrogen atoms as registersa quantity vastly greater than all the hydrogen in all the stars in this entire galaxy, and sixty-odd orders of magnitude greater than the capacity of the entire computing chamber, even if it had been filled entirely with hydrogen. The only way they could have succeeded was if they really were getting true quantum-computing effectshaving their limited number of physical registers existing simultaneously in multiple states superimposed one upon the other.
In a way, this next experiment was merely incrementaclass="underline" it was an attempt to factor an even bigger number. But the number in question was one of the vastly huge ones that Digandals Theorem said should be prime. No conventional computer could test that, but their quantum computer should be able to do so.
Ponter checked a few more pages of the printout, then went over to another control cluster and pulled some operational buds, adjusting parts of the recording system. He wanted to make sure that every facet of the run would be recorded, so that there could be no doubt afterward about the result. If they could just
Ready, said Adikor.
Ponter felt his heart begin to race. He so much wanted it to workboth for his own sake, and for Adikors, too. Ponter had had much luck early in his career; his was a respected name in physics circles. Even if he were to die today, he would be long remembered. Adikor hadnt been as successful, Ponter knew, although he surely deserved to be. How wonderful it would be for both of them if they could proveor disprove; either result would be significantDigandals Theorem.
There were two control clusters to be operated, one on each side of the small room. Ponter stayed at the one he was now at, next to the arch leading to the eating room; Adikor moved over to the other one on the opposite side of the room. All the controls should have been localized in one place, but this setup had saved almost thirty armspans worth of the expensive quantally transductive cable used to link the registers. Each control cluster was mounted on a wall. Adikor stood next to his and pulled the buds that needed pulling. Ponter, meanwhile, was operating the appropriate controls on his own cluster.
All set? asked Adikor.
Ponter looked at the series of indicator lights on his board; they were all red, the color of blood, the color of health. Yes.
Adikor nodded. Ten beats, he said, starting the countdown. Nine. Eight. Seven. Six. Five. Four. Three. Two. One. Zero.
Several lights flashed on Ponters board, showing that the registers were working. In theory, over the span of a fraction of a beat, all the possible factors had been tried, and the results had already been received as a series of interference patterns on photographic film. It would take the conventional computer that decoded the interference patterns a while to compose the list of factorswhich, if Digandal was wrong and this number wasnt prime, could be a very large list indeed.
Ponter left his console and moved to sit down. Adikor paced back and forth, looking out the window at the rows of register tanks, each a sealed glass-and-steel column containing a specific amount of hydrogen.
Finally, the conventional computer made a plunk sound, signaling that it had finished.
There was a monitor square in the center of Ponters control cluster; the results appeared on it in black glyphs on a yellow background. And the results were
Gristle! swore Adikor, standing behind Ponter, a hand on his shoulder.
The display read: Error in register 69; factoring aborted.
We have got to get that one replaced, said Ponter. Its given us nothing but trouble.
Its not the register, said Adikor. Its the base that holds it to the floor. But itll take tendays to get a new one made.
So we cant do anything before the Gray Council? asked Ponter. He didnt look forward to facing the elder citizens and saying that nothing had been added to our knowledge since the last Council session.
Not unless Adikor trailed off.
What?
Well, the problem with 69 is that it tends to vibrate on its base; the attachment clamps werent machined quite right. If we could find something to anchor it with
Ponter scanned the room. There was nothing that looked suitable. How about if I just go out on the computing floor and lean on it? You know, press down with all my weight. Wouldnt that keep it from vibrating?
Adikor frowned. Youd have to hold it very steady. The equipment can tolerate some movement, of course, but
I can do it, said Ponter. Butbut will my presence on the computing floor promote decoherence?
Adikor shook his head. No. The register columns are heavily shielded; it would take something a lot more radioactive or electrically noisy than a human body to upset the contents.
Well, then?
Adikor frowned again. Its hardly an elegant solution to the problem.
But it might work.
Adikor nodded. I suppose its worth a try. Better than going to Council empty-handed.
All right! said Ponter, decisively. Lets do it. Adikor nodded, and Ponter opened the door that separated the other three rooms from the large chamber containing the register tanks. He then walked down the steps to the rooms polished granite floor, which had been leveled with laser beams. Ponter moved carefully along it; hed slipped once before while crossing. When he got to cylinder 69, he placed one hand on its curved top, covered that with his other hand, and then pressed down with all his strength. Any time youre ready, Ponter shouted.
Ten, Adikor shouted back. Nine. Eight. Seven.
Ponter fought to keep his hands steady. As far as he could tell, the cylinder wasnt vibrating at all.
Six. Five. Four.
Ponter took a deep breath, trying to calm himself. He held it in.
Three. Two. One.
Here we go, thought Ponter.
Zero!
Adikor heard the glass rattle fiercely in the window looking over the computing floor. Ponter! he shouted. Adikor hurried to the window. P-Ponter?
But there was no sign of him.
Adikor pulled the grip that unlatched the door, and
Whoosh!
The door swung forward, flying open, the grip wrenched from Adikors hand as a great rush of air from the control room flew past him out into the computing chamber; it was almost enough to tumble Adikor face first down the small staircase. Air was rushing into the computing chamber from the control room and the mine beyond as ifas if somehow the air that had been in there earlier had all been sucked away. Adikors ears popped repeatedly.
Ponter! he called again once the wind had died down, but although the room was large, the register tanks, arrayed in a vast grid, were all narrow columns; there was no way Ponter could be concealed behind one of them.
What could have happened? If a rock wall elsewhere in the mine had collapsed, and behind it had been an area of low pressure, maybe
But there were seismic sensors throughout the mining complex, and theyd have triggered the release of warning smells here in the computing lab if there had been any such disturbance.
Adikor hurried across the granite floor. Ponter! he called again. Ponter?
There was no fissure in the flooring; he couldnt have been swallowed up by the ground. Adikor could see register tank 69, the one Ponter had been working on, at the far end of the room. Ponter obviously wasnt there, but Adikor ran over to the register, anyway, looking for any clue, and