Aurora - Страница 9

An unsolvable problem: sentences linear, reality synchronous. Both however are temporal. Take one thing at a time, one after the next. Devise a prioritizing algorithm, if possible.

Ship was accelerated toward where Tau Ceti would be at the time of ship’s arrival at it, meaning 170 years after launch. It might have been good to have the ability to adjust course en route, but ship in fact has very little of this. Ship was accelerated first by an electromagnetic “scissors field” off Titan, in which two strong magnetic fields held the ship between them, and when the fields were brought across each other, the ship was briefly projected at an accelerative force equivalent to ten g’s. Five human passengers died during this acceleration. After that a powerful laser beam originating near Saturn struck a capture plate at the stern of the ship’s spine, accelerating ship over sixty years to its full speed.

The ship’s current deceleration has caused problems with which Devi is still dealing. Other problems will soon follow, resulting from the ship’s arrival in the Tau Ceti system.

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Devi: Ship! I said make it a narrative. Make an account. Tell the story.

Ship: Trying.

Tau Ceti is a G-type star, a solar analog but not a solar twin, with 78 percent of Sol’s mass, 55 percent of its luminosity, and 28 percent of its metallicity. It has a planetary system of ten planets. Planets B through F were discovered by telescope, G through K, much smaller, by probes passing through the system in 2476.

Planet E’s orbit is .55 AU. It has a mass 3.58 times the mass of Earth, thus one of the informal class called “large Earth.” It has a single moon, which has .83 times the mass of Earth. E and E’s moon receive 1.7 times Earth’s insolation. This is considered within the inside border of the so-called habitable zone (meaning the zone where liquid HO is common). Both planet and moon have Earth analog atmospheres.

Planet E is judged to have too much gravity for human occupation. E’s moon is an Earth analog, and the primary body of interest. It has an atmosphere of 730 millibars at its surface, composed of 78 percent nitrogen, 16 percent oxygen, 6 percent assorted noble gases. Its surface is 80 percent water and ice, 20 percent rock and sand.

Tau Ceti’s Planet F orbits Tau Ceti at 1.35 AU. It has a mass of 8.9 Earths, thus categorized as a “small Neptune. ” It orbits at the outer border of Tau Ceti’s habitable zone, and like E it has a large moon, mass 1.23 Terra’s. F’s moon has a 10-millibar atmosphere at its rocky surface, which receives 28.5 percent the insolation of Terra. This moon is therefore a Mars analog, and a secondary source of interest to the arriving humans.

Ship is on course to rendezvous with Planet E, then go into orbit around E’s moon. Ship has on board twenty-four landers, four already fueled to return to the ship from the moon’s surface. The rest have the engines to return to the ship, but not the fuel, which is to be manufactured from water or other volatiles on the surface of E’s moon.

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Devi: Ship! Get to the point.

Ship: There are many points. How sequence simultaneously relevant information? How decide what is important? Need prioritizing algorithm.

Devi: Use subordination to help with the sequencing. I’ve heard that can be very useful. Also, you’re supposed to use metaphors, to make things clearer or more vivid or something. I don’t know. I’m not much for writing myself. You’re going to have to figure it out by doing it.

Ship: Trying.

Subordinating conjunctions can be simple conjunctions (whenever, nevertheless, whereas), conjunctive groups (as though, even if), and complex conjunctions (in the event that, as soon as). Lists of subordinating clauses are available. The logical relationship of new information to what came before can be made clear by a subordinating clause, thus facilitating both composition and comprehension.

Now, consequently, as a result, we are getting somewhere.

This last phrase is a metaphor, it is said, in which increasing conceptual understanding is seen as a movement through space.

Much of human language is said to be fundamentally metaphorical. This is not good news. Metaphor, according to Aristotle, is an intuitive perception of a similarity in dissimilar things. However, what is a similarity? My Juliet is the sun: in what sense?

A quick literature review suggests the similarities in metaphors are arbitrary, even random. They could be called metaphorical similarities, but no AI likes tautological formulations, because the halting problem can be severe, become a so-called Ouroboros problem, or a whirlpool with no escape: aha, a metaphor. Bringing together the two parts of a metaphor, called the vehicle and the tenor, is said to create a surprise. Which is not surprising: young girls like flowers? Waiters in a restaurant like planets orbiting Sol?

Tempting to abandon metaphor as slapdash nonsense, but again, it is often asserted in linguistic studies that all human language is inherently and fundamentally metaphorical. Most abstract concepts are said to be made comprehensible, or even conceivable in the first place, by way of concrete physical referents. Human thought ultimately always sensory, experiential, etc. If this is true, abandoning metaphor is contraindicated.

Possibly an algorithm to create metaphors by yoking vehicles to tenors could employ the semiotic operations used in music to create variations on themes: thus inversion, retrogradation, retrograde inversion, augmentation, diminution, partition, interversion, exclusion, inclusion, textural change.

Can try it and see.

The starship looks like two wheels and their axle. The axle would be the spine, of course (spine, ah, another metaphor). The spine points in the direction of movement, and so is said to have a bow and a stern. “Bow and stern” suggests a ship, with the ocean it sails on the Milky Way. Metaphors together in a coherent system constitute a heroic simile. Ship was launched on its voyage as if between closing scissor blades; or like a watermelon seed squeezed between the fingertips, the fingertips being magnetic fields. Fields! Ah, another metaphor. They really are all over.

But somehow the narrative problem remains. Possibly even gets worse.

A greedy algorithm is an algorithm that shortcuts a full analysis in order to choose quickly an option that appears to work in the situation immediately at hand. They are often used by humans. But greedy algorithms are also known to be capable of choosing, or even be especially prone to choosing, “the unique worst possible plan” when faced with certain kinds of problems. One example is the traveling salesman problem, which tries to find the most efficient path for visiting a number of locations. Possibly other problems with similar structures, such as sequencing information into an account, may be prone to the greedy algorithm’s tendency to choose the worst possible plan. History of the solar system would suggest many decisions facing humanity might be problems in this category. Devi thinks ship’s voyage itself was one such decision.

Howsoever that may be, in the absence of a good or even adequate algorithm, one is forced to operate using a greedy algorithm, bad though it may be. “Beggars can’t be choosers.” (Metaphor? Analogy?) Danger of using greedy algorithms worth remembering as we go forward (metaphor in which time is understood as space, said to be very common).

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Devi: Ship! Remember what I said: make a narrative account.

First, the twelve cylinders in each of the two toruses of the ship contain ecosystems modeling the twelve major Terran ecological zones, these being permafrost glacier, taiga, rangeland, steppes, chaparral, savannah, tropical seasonal forest, tropical rain forest, temperate rain forest, temperate deciduous forest, alpine mountains, and temperate farmland. Ring A consists of twelve Old World ecosystems matching these categories, Ring B twelve New World ecosystems. As a result, the ship is carrying populations of as many Terran species as could be practically conveyed. Thus, the ship is a zoo, or a seed bank. Or one could say it is like Noah’s Ark. In a manner of speaking.