Epimetheus is a misshapen pile of loosely consolidated rubble. It switches orbits with the moon Janus every eight years; they are co-orbital moons, very rare-a sign of past impacts.
Enceladus is covered by braided spills of ice. No craters-the ice surface is too new, as it is continuously resurfaced from the liquid-water ocean in the depths. Heat sources boil some of this carbonized water, creating geysers that shoot many kilometers into space. The water quickly freezes in its flight, and some of it makes it up to the slender E ring; the rest falls back down and under its own weight turns to firn and then back to ice again. A suite of microscopic life-forms was discovered in the Enceladan ocean in the year 2244, and scientific stations have been established on its surface, as well as a cult of votaries who ingest a suite of the alien life-forms, to unknown effect.
There are twenty-six irregular small moons. These are all Kuiper belt objects, captured as they crossed Saturn’s earliest gas envelope. Phoebe, at 220 kilometers across, is the largest of these, and it has a retrograde and highly inclined orbit, twenty-six degrees out of the plane; thus another popular viewing platform.
Titan, by far the largest Saturnian moon, is bigger than Mercury or Pluto. More about Titan later.
Extracts (9)
One question for computability: is the problem capable of producing a result
If a finite number of steps will produce an answer, it is a problem that can be solved by a Turing machine
Is the universe itself the equivalent of a Turing machine? This is not yet clear
Turing machines can’t always tell when the result has been obtained. No oracle machine is capable of solving its own halting problem
A Turing jump operator assigns to each problem X a successively harder problem, X prime. Setting a Turing machine the problem of making its own Turing jump creates a recursive effect called the Ouroboros
All problems solvable by quantum computers are also solvable by classical computers. Making use of quantum mechanical phenomena only increases speed of operation two popular physical mechanisms, dots and liquids. Quantum dots are electrons trapped inside a cage of atoms, then excited by laser beams to superposed positions, then pushed to one state or the other. Quantum liquids (often caffeine molecules because of the many nuclei in them) are magnetically forced to spin all their nuclei in the same spin state; then NMR techniques detect and flip the spins
Decoherence happens at the loss of superposition and the resulting either/or. Before that a quantum calculation performs in parallel every possible value that the register can represent
Using superposition for computation requires avoiding decoherence for as long as possible. This has proved difficult and is still the limiting factor in the size and power of a quantum computer. Various physical and chemical means for building and connecting qubits have increased the number of qubits possible to connect before decoherence collapses the calculation, but
Quantum computers are restricted to calculations that can be performed faster than decoherence occurs in the superposed wave functions. For over a century this restricted time for a quantum computing operation to less than ten seconds
Qubes are room-temperature quantum computers with thirty qubits, the decoherence boundary limit for circuit-connected qubits, combined with a petaflop-speed classical computer to stabilize operations and provide a database. The most powerful qubes are theoretically capable of calculating the movements of all the atoms in the sun and its solar system out to the edge of the solar wind
Qubes are only faster than classical computers when they can exploit quantum parallelism. At multiplication they are no faster. But in factoring there is a difference: to factor a thousand-digit number would take a classical computer ten million billion billion years (lifetime of universe, 13.7 billion years); using Shor’s algorithm, a qube takes around twenty minutes
Grover’s algorithm means that a yearlong search using a classical computer in a random walk of a billion searches a second would take a qube in its quantum walk 185 searches
Shor’s algorithm, Grover’s algorithm, Perelman’s algorithm, Sikorski’s algorithm, Ngyuen’s algorithm, Wang’s algorithm, Wang’s other algorithm, the Cambridge algorithm, the Livermore algorithm, entanglement is also susceptible to decoherence. Physical linkage of quantum circuits is necessary to forestall decoherence to useful time frames. Premature or undesired decoherence sets a limit on how powerful qubes can become, but the limit is high it has proved easier to manipulate superposition than entanglement for computing purposes, and therein lies the explanation of many
The quantum database is effectively distributed over a multitude of universes the two polarized particles decohere simultaneously no matter the physical distance between them, meaning the information jump can exceed the speed of light. The effect was confirmed by experiment in the late twentieth century. Any device that uses this phenomenon to communicate messages is called an ansible, and these devices have been constructed, but undesired decoherence has meant the maximum distance between ansibles has been nine centimeters, and this only when both were cooled to one millionth of a K above absolute zero. Physical limitations strongly suggest further progress will be asymptotic at best powerful but isolated and discrete, somewhat like brains questions of Penrose quantum effects in the brain have been effectively rendered moot, as these also occur in qubes by definition. If both structures are quantum computers, and one of them we are quite certain has consciousness, who is to say what’s going on in the other human brain operations have a maximum theoretical speed of 10 ^ 16 operations per second computers have become billions to trillions times faster than human brains. So it comes down to programming; what are the operations actually doing hierarchical levels of thought, generalization, mood, affect, will super-recursive algorithms, hypercomputation, supertasks, trial-and-error predicates, inductive inference machines, evolutionary computers, fuzzy computation, transrecursive operators, if you program a purpose into a computer program, does that constitute its will? Does it have free will, if a programmer programmed its purpose? Is that programming any different from the way we are programmed by our genes and brains? Is a programmed will a servile will? Is human will a servile will? And is not the servile will the home and source of all feelings of defilement, infection, transgression, and rage? could a quantum computer program itself?
WAHRAM AND SWAN AND GENETTE
Wahram saw Swan emerge from the lock door, looking around for him, and when she saw him, he waved, and then she did too, her expression pinched, he thought, her head tilted to the side. She looked at him in quick glances-she didn’t know how he would be. Suddenly he remembered that in the actual flesh she was a big bag of problems. He nodded a little deeper than he would have normally, trying to reassure her, and then thought that that might not be enough, and extended both hands, realizing as he did so that he was already back in a different world, Swancentric and intense. She threw herself on him in a rush, and he felt sure it looked like he was hugging back, or had even invited the hug.
Jean Genette emerged from the lock and stood looking up at them, and Wahram greeted him with another bow.
“So you want to find one of the hanging ships?” he said.
They did. Apparently it might have something to do with the attack on Terminator. So Wahram led them across the spaceport to the gate for the railgun launcher angled to send ferries into polar orbits around Saturn. These orbits were popular for viewing the rings and the hexagonal storm at Saturn’s south pole. Wahram had already gotten permission from the authorities to take a cloud diver into the upper reaches of the planet; probably the council was happy to have him involved, as the Saturnian liaison to the incursion.
They took off with only a pilot and crew aboard with them, and after they were cast toward the north pole, Swan and the inspector told Wahram what they had been doing since they’d left Mercury. Wahram, feeling uneasy that he could not fully reciprocate and tell them about his activities, given the council’s orders, compensated by asking them a lot of questions about the investigation and its results so far. These turned out to be very interesting, even disturbing, and Wahram pondered to the point of a certain distraction the idea that there might be someone out there killing whole terraria. That the investigation had reduced their likeliest suspect pool to the population of
