Allotropes

by Laurence Dahners

  Shan watched bemusedly as Raquel ate three of the large fish tacos he’d made.

  “These are great!” she said, then leaned forward on her elbows to look into his eyes. “I need some advice.”

  He shrugged. “Sure. What can I give you advice on?”

  “Well, first, I apologize for letting you think I was talking about Tau Ceti out there in my car. Actually, I was talking to Allan about Sigma Draconis.”

  “Really? I didn’t know you’d reached any other stars.”

  “Well, we’ve reached a world around Alpha Centauri. It has life on it but doesn’t seem to have anything multicellular. At least not that we can see from orbit. We’ve actually got some rockets nearing several other stars that don’t even have reasonably sized planets in the liquid water zone. We’re thinking of offering those rockets as viewing platforms to astronomers who might want to simply observe those systems optically.”

  Shan narrowed his eyes, “But it sounds like Sigma Draconis has more advanced life. Is it intelligent?”

  “Shan, they’ve built a ringworld.”

  “My God! All the way around the sun, like in Niven’s book?”

  “Oh, no! Niven’s ringworld wouldn’t have maintained a stable orbit and it would have to have been built out of material with absolutely impossible tensile strength. There are countless things on Niven’s ringworld that are not only impossible with current tech but will probably never be possible. No, the Sigma Draconis ring is only 20,000 kilometers in diameter. It’s turning eight revolutions per day. It could be constructed with carbon nanotubes or graphene, if you could make enough of those carbon allotropes.”

  “Holy crap Raquel! That’s still freaking enormous! A circumference of 63,000 kilometers! How wide is it?”

  “About 5,000 kilometers.”

  “So that’s what… 315 million square kilometers of surface!?”

  Ell nodded. “About 60% the surface area of the earth. A lot bigger than their homeworld.”

  “How thick is it?”

  “Can’t tell, but even if it were only five meters thick, that would still require 1.6 million cubic kilometers of carbon assuming they built it out of graphene.”

  Shan closed his eyes, “That kind of engineering… that’s just plain scary,” he whispered.

  Ell raised an eyebrow, “You’re telling me.”

  “So, is the life there DNA based?”

  “The first specimen, a plant, was.” Ell glanced up at her HUD. “Oh, and the second plant was DNA based too. Seems like the DNA molecule is pretty ubiquitous.”

  “What are the intelligent beings like?”

  “Haven’t seen one yet.”

  “Really? They built a ringworld but aren’t living there?”

  Ell shrugged, “I don’t know. So far all Sigwald has encountered are fields of what appear to be crops. At first they seemed to only be one type, but he’s just encountered a second kind of plant.”

  “Sigwald?”

  “My name for the waldo that’s actually on the ringworld.”

  He got a distant look, “Maybe the plants are intelligent?”

  Ell shrugged, “Can’t rule that out, but the plants we’ve seen don’t have hands. How would they build a ringworld?”

  “Can I see?”

  Ell ported the video from Sigwald to Shan’s HUD and he leaned back, flabbergasted as the view from Sigwald raced along the road between the fields. A road that shot arrow straight into the distance until even the transparent atmosphere had deflected enough light that nothing could be seen but a bluish haze. High in the far distance he thought perhaps he could see a wall rising up above the haze. “Is the bottom of the ring flat from side to side?”

  “No, it’s dished some toward the middle. In just a few minutes the sun will go down and you’ll be able to see the other side of the ring because that side’ll be the one lit by the sun. You’ll be able to see that there appears to be a blue circle sea running along the middle of the ring. That would fit with the middle being the deepest part of the ring. Water would run from the rims down to the central circle sea. A typical weather cycle could then evaporate water out of the sea. The water vapor would rise and move to the higher edges of the ring. When the air got to the higher altitudes near the rimwalls it would precipitate out as rain and start running back downhill across the fields again.”

  Shan glanced around the edges of the field of view in Sigwald’s camera, seeing some clouds he hadn’t paid attention to before. “Wouldn’t rain wash all the soil down to the sea without tectonics to raise some land again?”

  Quietly Ell said, “I think the ring’s like a huge hydroponic system. No real soil, other than the composting of previous crops to release soluble nutrients. They must have some way to pump nutrient elements back out to the edge of the ring because the water cycle alone would take all the nutrients out to the sea like you said. Of course, breakdown of the un-harvested plant matter in the composting would provide a lot of those nutrients.”

  Ringshadow—Ell didn’t think it was dark enough to call it “sunset”—swept over Sigwald. Ell had Allan tip his head back so Shan could look up at the other side of the ring, now so much more visible.

  “Wow! That’s… impressive. But so uniform, kinda uninspired. I’d like to think that if we’d built it, it wouldn’t be so… monotonous.”

  “Me too.” Ell almost whispered. “It’s hard to imagine what circumstance would cause them to build something like this. Is it just a farm?”

  “Hey, there’s something happening up ahead to the left.”

  Ell had Allan turn Sigwald’s head that way. They could see dust rising from something. “Shall we head over that way and have a look?

  “Yeah.”

  Allan slowed Sigwald and turned him to the left at the next intersection, then right again. Several such turns brought Sigwald fairly close to the disturbance. Slowing further the waldo crept around the next corner and stopped. They looked on in astonishment. A huge machine hung like a bridge all the way across the field. It hung from an impossibly lightweight looking spidery frame with huge spindly wheels that were rolling along the roads on each side of the field. A box in the middle looked like it might hold an operator. The dust they’d seen rose from the leading edge which was sucking in the tufted tops of the grain-like plants. Whatever processing it was doing to the tufts generated the dust, apparently fine plant debris. Behind the trailing edge of the huge machine all the plants—not just the tufts—were gone! As they watched, the machine stopped over the trough at the rimward edge of the field and disgorged a huge mass of vegetable matter. It appeared to be the chopped residue of the plants the machine had pulled up from the field. After a moment the machine resumed moving. It crossed the rimwall paralleling circle-road to the next field.

  As they stared after the machine they heard a flapping noise from behind Sigwald.

  When Sigwald’s head had turned they saw their first sigma.

  Querlak had nearly despaired of catching whatever was leaving the trail blown from the road’s dust. She had decided it must be moving at least as fast as her best flying speed, perhaps faster. Leaving her assigned inspection task would cost her unless she could demonstrate that a greater value to the sigmas had come from her pursuit. If she never caught the perpetrator of the plant damage, or if it had already been caught by someone else by the time she arrived, this detour of hers would be a total loss. While considering whether to turn back she briefly missed the fact that the trail in the dust had turned left. She saw the deviation just as she passed the intersection and had to fly back across the corner of the field. She found the trail again and followed it right at the next intersection.

  Then left again, and right after that. The diagonal travel the repeated turns produced took Querlak toward a harvester. She wondered if her fugitive intended to intersect with the harvester or if the chosen direction was accidental.

  At the next intersection Querlak’s eye caught on the huge harvester and she almost misse
d the small metallic object in the road. Just before overflying it she saw it and back beat her wings. Halted, she sank to the road behind the… thing? Wide eyed with surprise, Querlak immediately sent out a request for links and quickly established a TS with seven members. In human terms this boosted her IQ from about 70 to about 107. With this increased clarity, Querlak studied the object. It appeared to be made mostly of metal! Stationary now, the trail of disturbed dust led right up to it, indicating that it was indeed what Querlak had been following. It must have been moving moments ago.

  Because Sigma Draconis was a somewhat metal poor star and the sigmas’ home world had far less metal than earth, metal was precious to them. With limited access to metals in their civilization they’d learned to use carbon as their structural material of choice early on. They’d rapidly moved from plant cellulose, to carbon fiber, to nanotubes, to graphene, saving metals for other more important uses. They’d been making things from carbon for so long and did it so well and so cheaply that finding a structural object made from metal suggested wasteful extravagance to a sigma. It affected Querlak much like finding a gold car would strike a human. Carbon structure was cheaper, lighter and so, so much stronger. Making something out of metal suggested a clade that wished to impress with its wealth.

  Then the top of the object rotated and faced Querlak. It had two lenses reminiscent of eyes but arranged horizontally!

  Astonished and feeling out of her depth with just a seven person TS, Querlak put out a call for more members. The clade connected thirteen more sigmas to her, boosting her IQ to approximately 124. Because Querlak’s clade wasn’t large, taking this many members away from their assigned tasks to help process this single phenomenon represented a large commitment, but no one complained. This… object… or machine… or being… represented a singular event in sigma history.

  The 20 person TS studied the metal object. Most, if not all of it looked like it was made of the twelfth element magnesium. Magnesium was the second most common metal after iron and much lighter. If you were going to make a mobile artifact out of metal, using magnesium would make some sense. Still magnesium was a lot heavier than carbon and much, much weaker, why would anyone do that? The object stood on two lower projections and had two upper projections that looked like they might be used for manipulation. Why so few?

  As Querlak watched, the bottom two projections moved independently to rotate the entire object so that the opposite side of the object now faced toward Querlak. The TS decided from their movements that the lower projections were in fact legs of some sort. The lenses or eyes at the top rotated as the object did so that they remained facing Querlak. Surprisingly, despite having legs like an animal, the object had no wings! Querlak had, of course, never seen an animal, but records showed that a few of the historical animals of the sigmas’ home world had lived flightless lives. However, even those animals had possessed vestigial wings. The first truly successful body plans on the sigmas’ home world had all had wings, so essentially all animals, even the few flightless ones, had descended from winged ancestors.

  Querlak wondered, could the object be some kind of metallic animal? It seemed so misshapen. Only two legs and those very thick and blocky. Only two arms, also overly bulky and powerful looking. No wings. The rotating part up top with the presumed eyes on it, that almost made sense, but it seemed much larger than it needed to be. And why only two eyes in a horizontal arrangement? Querlak knew that you had to have more than one eye to have depth perception which was determined by the angle between the two eyes and an object. But why two medium sized eyes rather than one large high quality eye with a few, little, low quality, wide angle eyes that served only to determine the angle to an object and watch the periphery? Such an arrangement had been nearly universal for the animals on Sigma. As Querlak studied the eyes, she realized that the two eyes pivoted and swiveled toward and away from one another as if both had high acuity vision and measured the angle to an object by the direction they were pointed! This seemed highly inefficient as compared to a single very high acuity eye with low acuity ones that only registered direction by where light fell on their receptors…

  Everything about the strange… object… seemed so bizarre. If it was an animal, how had it evolved so strangely and why had no one in her clade ever heard of one? If someone had built it as a device… why!? And if you were going to build a strange animal-like device, why such a bizarre layout of parts? Why magnesium?! It must be difficult to balance it on only two legs. Its thick and heavy metal construction would be so expensive and require so much power just to move it! It almost seemed like someone had made it as a joke… a hugely expensive joke.

  Shan and Ell gawked at the sigma on their screens. It had four long, slender, multijointed legs that seemed somewhat insectile. They looked too small to hold it up, but of course the gravity was low. The four wings came off the nearly horizontal body, one pair forward, the other pair nearer the back. Four lightweight limbs at the front had three digits each. They appeared to be for manipulation.

  Sprouting from between the “arms” was a somewhat heavier limb with what appeared to be eyes near its end. Because of the eyes Ell categorized that limb as a “head” even though it seemed too small to be a head. Of course, the teecees had a small and prehensile head too. The teecee’s brains were in the main body rather than in the head so that might be true here too. The sigma’s head was barely wide enough for what appeared to be one very large eye. The head narrowed above that, where some smaller eyes formed a column going up to the top of the head and perhaps even over the top to the back? The eyes didn’t appear to swivel like earth’s animal’s eyes do. Rather the sigma seemed to move the entire head to point it at things. Right now it tilted up, then down as if examining Sigwald from top to bottom. Then the head swayed to the left and right, turning the eye back toward Sigwald from each side. The head didn’t seem to have ears, or a mouth, or actually, an orifice of any kind.

  Ell had Allan lift one of Sigwald’s hands slowly to a palm forward position. She wondered if this peaceful human gesture would be perceived as friendly by the sigma. She turned to Shan, “I’ve got to get to my house where I’ll have better control of the waldo. Do you want to come with?”

  “I thought I wasn’t to be seen at your place?”

  “We’ll have to sneak you in,” she said, getting up.

  They drove to the house that Ell’s security team kept in the neighborhood next to her little farm. In transit they watched the sigma on their HUDs. It didn’t move but they could hear it making noise. No mouth moved so it wasn’t clear where the sound came from.

  They parked in the security team’s garage and hustled down into the tunnel. As they rode the golf cart through the tunnel to Ell’s house the sigma began gesticulating on their HUDs. As they couldn’t walk and watch their HUDs very well, Ell wound up leading Shan by the hand so that at least one of them could watch the movements of the sigma’s hands. None of the motions made much sense to Shan though.

  Once in the house, they went to the extra bedroom where Ell had another one of her waldo controllers. Ell mounted the controller saddle and had the images from Sigwald thrown up on the big screen for Shan. Once she had control of Sigwald she squatted down and made a mark in the dust on the black surface of the roadway.

  The mark was visible, though she could have wished for something better. She made two marks next to it and then pointed to the single mark, saying, “One.” She pointed to the double mark and said, “Two.” She made three marks and said, “Three.” She had considered having Sigwald project marks with his laser, but in the bright daylight she didn’t think they would be very easy to see.

  Ell waited a moment, then pointed at the single mark while looking at the sigma. When the sigma said nothing Ell began again, pointing at the single mark and saying, “One,” then moving on to the double and triple marks.

  Ell pointed at the single mark once again while looking expectantly at the sigma. It was relatively easy to tell wha
t the sigma was looking at because its entire head would move and tilt in that direction. First it looked down at the marks, moving from one to another, then it looked up at Sigwald, then back down at the marks. Then two arms reached out and touched the single mark and it uttered a sound. It sounded a little like a chorus of voices humming in different pitches.

  The sound wasn’t something that Ell could reproduce so she told Allan to make the sound back at the sigma while she reached out and touched the single mark again. Once Sigwald had reproduced the sound the sigma made, she moved on to the double mark and said, “Two.”

  The sigma pointed back at the single mark and said, “One,” in English, then pointed at the double mark and said, “Two.” After a moment the sigma uttered another sound that Ell would be unable to reproduce, then pointed to the triple mark and made a third sound, then looked expectantly at Sigwald.

  Ell had Allan copy the sigma’s sound, then said, “Three.”

  It didn’t take long to get through the numbers and determine that the sigmas used base 12 counting. Ell moved Sigwald closer to where the harvester had passed. The thicker dust on the road made writing easier there. She drew a picture of the ring and said, “Ringworld.”

  Over the next several hours they exchanged words for the objects in their immediate vicinity and in the sigma’s solar system. The name of the sigma they were speaking to sounded like “Querlak,” if the word were to be spoken by an off key choir. They derived units of measurement from the dimensions of the system and of the ringworld and the road itself. They named the plants and each other and their various parts. Learning body parts allowed Ell to examine the sigma. A crevice beneath the bases of the arms looked as if it might be a mouth but it remained closed while the sigma spoke. Querlak had a number of openings around its body that Ell thought it was breathing through. Though Ell couldn’t localize sound well through Sigwald’s microphones she thought that perhaps the sigma made sounds through those same breathing holes.