StarDestroyer.Net BBS

brianeyci wrote:The non-terminating non-repeating process are the gliders as far as I can tell. Don't ask me how to model it mathematically though .

Destructionator XIII wrote:That is an interesting enough question that you got me to crack open my text editor and compiler. I should be able to code that, somewhat easily, since the game is so simple.

Destructionator XIII wrote:So the code is pretty much dealing with a rectangle that wraps around at the edges, then it can be rendered either as this rectangle (since we are basically dealing with a surface area), or rendered in 3d by applying the same parametric equations again.

Jaepheth wrote:I don't think you could have a non-repeating and non-terminating progression since there's a finite number of squares and hence a finite number of possible combinations on the board (albeit a large number of combinations)

Steven Levy wrote: It was in 1970 that Bill Gosper began hacking LIFE. It was yet another system that was a world in itself, a world where behavior was "exceedingly rich, but not so rich as to be incomprehensible." It would obsess Bill Gosper for years.

LIFE was a game, a computer simulation developed by John Conway, a distinguished British mathematician. It was first described by Martin Gardner, in his "Mathematical Games" column in the October 1970 issue of Scientific American. The game consists of markers on a checkerboard-like field, each marker representing a "cell." The pattern of cells changes with each move in the game (called a "generation"), depending on a few simple rules cells die, are born, or survive to the next generation according to how many neighboring cells are in the vicinity. The principle is that isolated cells die of loneliness, and crowded cells die from overpopulation; favorable conditions will generate new cells and keep old ones alive. Gardner's column talked of the complexities made possible by this simple game and postulated some odd results that had not yet been achieved by Conway or his collaborators.

Gosper first saw the game when he came into the lab one day and found two hackers fooling around with it on the PDP-6. He watched for a while. His first reaction was to dismiss the exercise as not interesting. Then he watched the patterns take shape a while longer. Gosper had always appreciated how the specific bandwidth of the human eyeball could interpret patterns; he would often use weird algorithms to generate a display based on mathematical computations. What would appear to be random numbers on paper could be brought to life on a computer screen. A certain order could be discerned, an order that would change in an interesting way if you took the algorithm a few iterations further, or alternated the x and y patterns. It was soon clear to Gosper that LIFE presented these possibilities and more. He began working with a few AI workers to hack LIFE in an extremely serious way. He was to do almost nothing else for the next eighteen months.

The group's first effort was to try to find a configuration in the LIFE universe which was possible in theory but had not been discovered. Usually, no matter what pattern you began with, after a few generations it would peter out to nothing, or revert to one of a number of standard patterns named after the shape that the collection of cells formed. The patterns included the beehive, honey farm (four beehives), spaceship, powder keg, beacon, Latin cross, toad, pinwheel, and swastika. Sometimes, after a number of generations, patterns would alternate, flashing between one and the other: these were called oscillators, traffic lights, or pulsars. What Gosper and the hackers were seeking was called a glider gun. A glider was a pattern which would move across the screen, periodically reverting to the same pointed shape. If you ever created a LIFE pattern which actually spewed out gliders as it changed shape, you'd have a glider gun, and LIFE'S inventor, John Conway, offered fifty dollars to the first person who was able to create one.

The hackers would spend all night sitting at the PDP-6's high-quality "340" display (a special, high-speed monitor made by DEC), trying different patterns to see what they'd yield. They would log each "discovery" they made in this artificial universe in a large black sketchbook which Gosper dubbed the LIFE Scrap-book. They would stare at the screen as, generation by generation, the pattern would shift. Sometimes it looked like a worm snapping its tail between sudden reverses, as if it were alternating between itself and a mirror reflection. Other times, the screen would eventually darken as the cells died from aggregate overpopulation, then isolation. A pattern might end with the screen going blank. Other times things would stop with a stable "still life" pattern of one of the standards. Or things would look like they were winding down, and one little cell thrown off by a dying "colony" could reach another pattern and this newcomer could make it explode with activity. "Things could run off and do something incredibly random," Gosper would later recall of those fantastic first few weeks, "and we couldn't stop watching it. We'd just sit there, wondering if it was going to go on forever."

As they played, the world around them seemed connected in patterns of a LIFE simulation. They would often type in an arbitrary pattern such as the weaving in a piece of clothing, or a pattern one of them discerned in a picture or a book. Usually what it would do was not interesting. But sometimes they would detect unusual behavior in a small part of a large LIFE pattern. In that case they would try to isolate that part, as they did when they noticed a pattern that would be called "the shuttle," which would move a distance on the screen, then reverse itself. The shuttle left behind some cells in its path, which the hackers called "dribbles." The dribbles were "poison," because their presence would wreak havoc on otherwise stable LIFE populations.

Gosper wondered what might happen if two shuttles bounced off each other, and figured that there were between two and three hundred possibilities. He tried out each one, and eventually came across a pattern that actually threw off gliders. It would move across the screen like a jitterbugging whip, spewing off limp boomerangs of phosphor. It was a gorgeous sight. No wonder this was called LIFE the program created life itself. To Gosper, Con-way's simulation was a form of genetic creation, without the vile secretions and emotional complications associated with the Real World's version of making new life. Congratulations you've given birth to a glider gun!

Early the next morning Gosper made a point of printing out the coordinates of the pattern that resulted in the glider gun, and rushed down to the Western Union office to send a wire to Martin Gardner with the news. The hackers got the fifty dollars.

This by no means ended the LIFE craze on the ninth floor. Each night, Gosper and his friends would monopolize the 340 display running various LIFE patterns, a continual entertainment, exploration, and journey into alternate existence. Some did not share their fascination, notably Greenblatt. By the early seventies, Greenblatt had taken more of a leadership role in the lab. He seemed to care most about the things that had to be done, and after being the de facto caretaker of the ITS system he was actively trying to transform his vision of the hacker dream into a machine that would embody it. He had taken the first steps in his "chess machine," which responded with a quickness unheard of in most computers. He was also trying to make sure that the lab itself ran smoothly, so that hacking would progress and be continually interesting.

He was not charmed by LIFE. Specifically, he was unhappy that Gosper and the others were spending "unbelievable numbers of hours at the console staring at those soupy LIFE things" and monopolizing the single 340 terminal. Worst of all, he considered the program they were using as "clearly non-optimal." This was something the LIFE hackers readily admitted, but the LIFE case was the rare instance of hackers tolerating some inefficiency. They were so thrilled at the unfolding display of LIFE that they did not want to pause even for the few days it might take to hack up a better program. Greenblatt howled in protest "the heat level got to be moderately high," he later admitted and did not shut up until one of the LIFE hackers wrote a faster program, loaded with utilities that enabled you to go backward and forward for a specified number of generations, focus in on various parts of the screen, and do all sorts of other things to enhance exploration.

Greenblatt never got the idea. But to Gosper, LIFE was much more than your normal hack. He saw it as a way to "basically do science in a new universe where all the smart guys haven't already nixed you out two or three hundred years ago. It's your life story if you're a mathematician: every time you discover something neat, you discover that Gauss or Newton knew it in his crib. With LIFE you're the first guy there, and there's always fun stuff going on.

You can do everything from recursive function theory to animal husbandry. There's a community of people who are sharing these experiences with you. And there's the sense of connection between you and the environment. The idea of where's the boundary of a computer. Where does the computer leave off and the environment begin?"

Obviously, Gosper was hacking LIFE with near-religious intensity. The metaphors implicit in the simulation of populations, generations, birth, death, survival were becoming real to him. He began to wonder what the consequences would be if a giant supercomputer were dedicated to LIFE ... and imagined that eventually some improbable objects might be created from the pattern. The most persistent among them would survive against odds which Gosper, as a mathematician, knew were almost impossible. It would not be randomness which determined survival, but some sort of computer Darwinism. In this game which is a struggle against decay and oblivion, the survivors would be the "maximally persistent states of matter." Gosper thought that these LIFE forms would have contrived to exist they would actually have evolved into intelligent entities.

"Just as rocks wear down in a few billion years, but DNA hangs in there," he'd later explain. "This intelligent behavior would be just another one of those organizational phenomena like DNA which contrived to increase the probability of survival of some entity. So one tends to suspect, if one's not a creationist, that very very large LIFE configurations would eventually exhibit intelligent [characteristics]. Speculating what these things could know or could find out is very intriguing ... and perhaps has implications for our own existence."

Gosper was further stimulated by Ed Fredkin's theory that it is impossible to tell if the universe isn't a computer simulation, perhaps being run by some hacker in another dimension. Gosper came to speculate that in his imaginary ultimate LIFE machine, the intelligent entities which would form over billions of generations might also engage in those very same speculations. According to the way we understand our own physics, it is impossible to make a perfectly reliable computer. So when an inevitable bug occurred in that super-duper LIFE machine, the intelligent entities in the simulation would have suddenly been presented with a window to the metaphysics which determined their own existence. They would have a clue to how they were really implemented. In that case, Fredkin conjectured, the entities might accurately conclude that they were part of a giant simulation and might want to pray to their implementors by arranging themselves in recognizable patterns, asking in readable code for the implementors to give clues as to what they're like. Gosper recalls "being offended by that notion, completely unable to wrap my head around it for days, before I accepted it."