Dark as Day

by Charles Sheffield

  Something she had brought with her from Argus Station, more important than clothing or personal effects, was her own suite of processing programs. She had no illusions that they were better than anyone else’s; what she was sure was that they were different. Also, they were hers, and she knew them inside-out.

  She began her analysis. It was similar to what she had attempted months ago, with one crucial difference: she could now build on everything established or conjectured by the Puzzle Network group. The start-stop coding sequence was known. She was sure of the integers. Perhaps most important of all, she knew that what she was dealing with was a signal. Puzzles always become easier when you know that a solution exists.

  The section that she clipped out for inspection was only a small section of the whole, roughly a hundred million digits out of twenty-one billion. You could eat that up very quickly with images, but she had deliberately avoided low-entropy data runs. What she hoped to find was “text”—whatever that term might mean to an alien mind. It was too early in the game to hope for keys to an actual language.

  After the first few minutes, Milly entered the twilight zone. Her mind became a place where symbols took on their own life and formed their own relationships. The signal contained dozens of these, short and well-defined strings that had been identified by other workers as common repeat patterns, but were not yet understood as to meaning. Sometimes the unknown strings appeared close to known integers, sometimes they coupled only to other unknowns. At this stage of understanding, the “knowns” lay within a great quagmire of uncertainties. The trick—if a trick existed—was to stand on a firm starting-point, something you definitely understood, then discover a sequence that allowed you to scramble out along it to reach another point of understanding.

  Milly worked on, oblivious to where she was or how long she had been sitting there, until she found her attention returning, again and again, to a sequence containing only a few tens of thousands of digits. She had culled it piece by piece from the sea of a hundred million bits, without knowing at a conscious level what she accepted and what she rejected.

  What made these samples different from any random selections? They seemed like a meaningless mixture. The pattern, if it could be called a pattern, comprised sets of small integers, always separated from each other by a repeated string. That string always contained the same twenty binary digits, and it could indicate an actual number but more likely stood for a symbol of some kind. Milly gave it a name. Call it the 20-bit “connector.” Each block of connector-number-connector had its own start and stop codes, separating it from other blocks.

  Milly substituted the word “connector” in the data set in place of the 20-bit strings, put decimal numbers in place of their binary integer equivalents, and read the result.

  On the face of it, she didn’t have much. Here was eight-connector-six-connector-eight, followed by the end-of-block marker. Here was eight-connector-seven-connector-eight, which was numerically almost the same, and another block end marker. But next to that sat the group one-connector-eight-connector-one, and then the more mysterious one-one-connectorconnector-six-connectorconnector-one-one.

  Signifying?

  Milly concentrated until the numbers and words swam and wandered and wobbled in front of her eyes. Pattern recognition was what humans did well, better than any computer so far built.

  There had to be a pattern, right?

  Right! So recognize it!

  The display sneered back at her, Right! If you can!

  Milly closed her eyes, took a deep breath, and sat motionless for a long time. At the conscious level, she seemed to be drifting from thought to random thought. But when she opened her eyes she was changing the word “connector” on the display to the symbolic “—”.

  The section she had been looking at became: 8—6—8, 8—7—8, 1—8—1, 1,1— —6— —1,1. If anything, that was more confusing than before.

  And then, suddenly, it was not confusing at all. Milly shivered and rubbed her eyes. How dense could you get? Before she started, she had told herself the order in which a rational being would try to construct meaningful messages: mathematics, then physics, then chemistry. When that was done, you could consider interpreting biology and language.

  Mathematics they had, at least at the level of the integers. It might be months or years before they advanced to complex variables and algebraic topology and the theory of continuous groups, but you did not need all those for a start on other subjects.

  In physics and chemistry, what was the most obvious and fundamental information a message might offer? The periodic table was a basic building block, invariant across the universe. Hydrogen came first, helium second, lithium third, and so on right up through all the stable elements. Carbon was sixth, nitrogen seventh, oxygen eighth, and you had absolutely no choice in those assignments.

  So now:

  8—6—8: carbon dioxide, complete with the symbol for a chemical bond.

  8—7—8: nitrous oxide.

  1—8—1: hydrogen-oxygen-hydrogen—water. If you were a human, you would have placed that first. Did it occur more frequently than the other symbols? Milly would have to go back and check.

  And 1,1— —6— —1,1? The dash was a clumsy notation for a two-or three-dimensional bond, but the reader was presumed to be intelligent. This one was methane, CH4, carbon with single bonds to four hydrogen atoms. Maybe the 2-D or 3-D representation would be found elsewhere in the signal, but meanwhile this would suffice. Scanning the whole sequence, Milly could see more complex patterns. She was reading a tutorial in elementary chemistry, one which confirmed at the same time that the natural numbers represented the elements.

  It wasn’t a great discovery, maybe it was just one small step up the mountain of understanding involved in deciphering an alien message. But it was her step, one that no one else had ever taken. Milly didn’t just want to post it on the Puzzle Network displays. She wanted to tell somebody, shout it to the world before her brain burst and the information was lost.

  She stood up quickly, swayed, and grabbed the edge of the console. She came close to blacking out and had to drop back into her seat to save herself.

  As dizziness receded she glanced over to see what time it was. Well past midnight. At once she knew what was happening. It was her old problem. She had sat alone in her cubicle, oblivious to everything but the displays and her own thoughts, for more than half a day. Now that she was again aware of her body, her mouth was dry and her throat felt as though it could not swallow. She needed a drink, and she needed to go to the bathroom—and both those things took priority over the table of the elements.

  She stood up, more carefully this time, and eased her way to the cubicle door and out into the corridor. She did not know where the bathroom was, but instinct told her that there must be one close to a conference room. She moved slowly along the corridor to the end, supporting herself with a hand on the wall and glad now that all the doors were closed.

  In the bathroom she relieved herself, then drank from a faucet and splashed cold water over her face and wrists.

  She went back out into the deserted corridor. In her muddled-headed condition she had not noticed before how quiet and dark it was. Everyone else in the Puzzle Network team must have gone to bed long ago, and she should do the same. Her brain was not going to burst. She would post her discovery tomorrow.

  Milly walked back toward the entrance, slowly and wearily. Halfway there, her nose picked up a faint and infinitely attractive aroma. Someone had been cooking, and in her starved state the smell was ambrosial.

  She tracked the food scent to a particular closed door, and stood in front of it. Every tissue in her body called out for instant nourishment. If there happened to be leftovers, surely the person who had prepared the dish would not begrudge them to Milly? She would leave a note, explaining what had happened and promising to replace whatever she ate.

  Her mouth, dry five minutes ago, was watering. She eased open the door of the cubicle.
The lighting inside was at a low setting, but she could see the food stand and a big brown crockpot sitting on top of it. The handle of a ladle pointed invitingly to Milly.

  She had taken two quick paces and was reaching out a hand when she realized that the room was not empty after all. A huge person, big enough to obscure half the cubicle’s display screens, squatted on a flat padded chair. As Milly dropped back a step, the black-clad hulk turned toward her.

  28

  Is this it?” Uncle Karolus placed a closed transparent container the size and shape of a small thimble on the table. “I wanted to be sure we were talking about the same thing before I go ahead and give it to the test team.”

  It was the middle of the night in Alex’s living quarters. Karolus, black-caped and hooded, had entered without warning to be greeted by a sleepy and startled Kate wearing only a short nightie. He gave her an appreciative leer before Alex appeared from the bedroom and she could retire into it.

  Alex blinked in the brighter light of the living-room and picked up the miniature vial. He lifted it close to his eyes, peering at the contents. It contained a dark-gray liquid that moved sluggishly as he tilted it.

  “It doesn’t look right,” he said. “The way it was described to me, there should be a lot of little balls in there.”

  “There are. At least, one of the Ligon techs took a quick look with a microscope and said there were. They’re real tiny, so they move around as though they’re a liquid.”

  “Then I guess this is what we need. Did you have to come here in the middle of the night?”

  “I thought we agreed this whole thing should be completed as fast as possible. Does your fat friend still say he’ll assign Pandora to us?”

  “For a full year, as soon as the tests are finished and we deliver the results. He’s grumbling a lot, but he already vacated Pandora and came to Ganymede. He wants the Ops Center finished before he goes back.”

  “Then let’s get the tests over and done with, before he changes his mind. Who has the list?”

  “Nobody. Bat described one series of experiments that I already passed on to Bengt Suomi, but he wants our people to feel free to add any more physical tests they can think of. He’s convinced that when the right experiment is performed, we’ll know it. I told Bengt Suomi that Bat is expecting some spectacular result, and you know Bengt. He can’t wait to get started.”

  “I believe that.” Karolus sniffed. “I’ll give Suomi the go-ahead tonight. Then the trouble will be stopping him. I never met a scientist yet who didn’t want to do just one more experiment.”

  Alex was still holding the little cylinder, and he moved it around so that the contents swirled up the rounded sides. “Are you sure that these samples were taken from the man I told you about, in science research quarantine?”

  “Either they were taken from Sebastian Birch, which is what I was told, or somebody in science research quarantine is going to suffer a greatly reduced life expectancy.”

  “How did you get them?”

  “You don’t know.” Karolus reached out and took the container from Alex’s hand. “And you don’t want to know. I’ll tell you this, though. Gram for gram, the gray mess in this bottle is the most expensive material in the solar system. It had better be worth the price.”

  “Bat is convinced that it will be.”

  “Do you have any idea why he’s so hot for this?—not that it’s any of our damned business.”

  “He’s convinced that it’s somehow connected to a weapon, and a woman who died at the end of the Great War.”

  “The war?” Karolus scowled. “My God, the war was over thirty years ago. Battachariya must be off his head.”

  Alex recalled Bat in the kitchen of the Bat Cave, peering into a steaming cauldron of bouillabaisse, muttering, tasting, and adding a single grain of cumin. “I wouldn’t say that. He is a little eccentric. But he cooks and serves better food than I’ve ever had from the Ligon chefs or anyone else.”

  “Really?” Karolus raised his bushy eyebrows. “That’s quite a claim. I wouldn’t mind tasting some myself. Good luck to him. I’m not a man to deny another his little pleasures—whatever they are. Which is my cue to leave and wake up Bengt Suomi, and yours to go back in there and service your extremely attractive friend.”

  Karolus stood up and pulled the black hood over his head. “Make sure Battachariya knows we are keeping our part of the deal.”

  “I will.”

  “I tell you, young Alex, these past few weeks have left me much encouraged. Hector honking Lucy Mobarak, you honking your own boss, no less, and the pair of you locking in the deal for Pandora. Meanwhile Great-aunt Agatha, that ghastly old hag, is heading for the bone yard. There’s hope for the family yet.”

  He bulled his way out. Alex locked the door behind him, reflecting that there would not be much hope for the Ligon family until Uncle Karolus joined Great-aunt Agatha.

  It was not reassuring to return to the bedroom and hear Kate, sitting cross-legged on the bed, say, “So that was the dreaded Karolus. You keep telling me that he’s terrible, but you know, I though he was rather fascinating. He introduced himself to me most politely.”

  “Right. Most polite. As he was leaving he told me to get back in there and service my extremely attractive friend.”

  “Did he really? Extremely attractive? Polite, and a man of discernment, too. But not again, not tonight. Come to bed. Tomorrow we go three more rounds on your predictive model with Ole Pedersen. We need sleep.”

  As if she needed to remind him. Alex, once again comfortably in bed with Kate nestled into his back, felt a sudden attack of the midnight blues. Hector was going to receive the credit for the Mobarak merger and for the deal with Bat. Ole Pedersen, or, even worse, moronic Macanelly, would be given credit for success with the predictive model—alien influence and all, which was no longer wild speculation since the news blurts were full of the Wu-Beston anomaly and the current work on signal deciphering.

  And Alex?

  A mere anonymous courier, running between Bengt Suomi’s lab and Rustum Battachariya, relaying other people’s wish lists and results, all to be forgotten a year from now? Or, just as bad, the creator of a predictive model which consumed large amounts of the Seine’s computer resources and produced nothing more than a bad example of mistaken concepts that would be recorded as part of the long history of modeling?

  Alex fell asleep trying to decide which was better. Would you rather be forgotten, or blamed?

  29

  Sluiced. Until Jan heard that word, she had not been sure of her own plans. Now she knew. The idea that Sebastian’s body would be invaded and taken over by self-replicating tiny machines, producing changes that no one could predict, filled her with horror. Even if no one else worried about the experiment—it was no better than an experiment, no matter what Valnia Bloom might say—she had to stick close to Sebastian and keep an eye on him.

  He seemed more stolid and indifferent than ever. He didn’t seem to know or care what was done to him. It was Jan or Valnia Bloom who, day by day, checked progress in the nano development. The chief technician, Hal Launius, insisted that the job was a simple one, with no chance of going wrong. He was confident and almost as casual in manner as Sebastian. It was left to Jan to do the worrying. She knew that never in human history had anyone developed a system incapable of failure.

  She made sure that she was present when the completed product was delivered. She sat and watched as Hal Launius displayed the spray syringe. It was tiny, more like a toy than a medical instrument. The tube held a few drops of misty gray-blue liquid, innocuous in appearance; but Jan could not repress a shiver when Launius applied the syringe’s tip to Sebastian’s bared upper arm. The liquid vanished instantly, absorbed through the skin.

  “Feeling all right?” Valnia Bloom, to judge from her voice, was more concerned than she would admit.

  “Yeah.” Sebastian sat dull-eyed. “Fine.”

  Jan wasn’t. “What happens next?”r />
  “For a few hours, nothing at all.” Hal Launius examined the empty syringe and nodded in satisfaction. “After that, the nanos will have multiplied enough to make themselves felt. Sebastian, you will run a fever—no more than a degree or two, I expect—and then you’ll need to pee a lot. That’s how the nodules will be excreted. Make sure that you drink plenty of fluids to help your kidneys.”

  “When will it end?” Valnia Bloom asked. “Before we began, you suggested four or five days would be enough.”

  “I was being conservative. Safer to play it that way.” Launius packed away the syringe in its little carrying case. “But if this isn’t all over and done with in three days or less, I owe you dinner.”

  He left. Valnia Bloom followed him a few minutes later, after advising Sebastian that his temperature and pulse would be monitored remotely and reminding him that water would help to flush out his system. Jan watched him closely. For all the notice he took of Valnia Bloom’s words, she might as well have saved her breath.

  Then Jan and Sebastian were alone. It was no novelty, they had been alone together most of their lives. But since leaving Earth, things had changed. Perhaps it was Sebastian, perhaps it was Jan, but what had once been easy companionship was now awkward. Sebastian never started a conversation. His replies were only a few words. He seemed preoccupied, far off in some private world.

  Jan stuck it out for three hours. At last she told Sebastian that she needed to go outside for “a breath of air”—a notion utterly alien to a Ganymede native. He simply nodded. She left the research quarantine facility and headed upward. The surface itself lay only four habitat layers above their heads.

  Jan had made no conscious plan as to what she would do next. It seemed like random impulse when she looked for and located a surface access point, donned one of the protective suits with its superconducting fine mesh, and proceeded upward one more layer and out through multiple locks onto the naked surface of Ganymede.