Notes for the Lifebox, the Seashell, and the Soul - Rudy Rucker

More documents

Recommendations

Info

Notes for The Lifebox, the Seashell, and the Soul, by Rudy Rucker This approach produces a phenomenon called numerical instability, meaning that all the cell values have a strong oscillation from generation to generation, producing artifacts such as a persistent domain boundaries and a checkerboard pattern. Be that as it may, the rule is computationally interesting. The unstable generational oscillations are more or less in synch across all the cells, so patterns are in fact able to emerge. The figure in the text shows scrolls in a version of this rule where each cell looks only at its four nearest neighbors, we use a logistic growth factor A of 2.1 and a diffusion rate B of 0.8. (Note that our A value of 2.1 is what Ralph Abraham’s paper would call 0.5025, as he multiplies his A by a factor of 4.) In the figure shown in the text, the checkerboard pattern has been reduced both by showing the differences between cells and their neighbors and by coloring nearby values the same. The domain boundaries are visible as looping lines. Over time these loops will shrink and disappear, leaving one or more loops that wrap all the way “around” the simulation space which, as usual, identifies the left and right edges and the top and bottom edges. To me, the Kaneko-Abraham method seems unnatural in that the diffusion and logistic operations are in some sense out of synch. Essentially each cell does a logistic update and then does diffusion based on its values before the logistic update. I would have expected better results from a rule in which all the cells diffuse their values first and only then do a logistic update. diffusion = B•(Average of neighboring population values - pop) newpop = Logistic(A, pop + diffusion) This approach does give smoother, somewhat less unstable patterns, but I’ve been unable to find Zhabotinsky scrolls with it ⎯ at best I’ve come up with some Turing spots. As I discuss in the text, when I use this second approach to the algorithm with two species, I had good success. Artificial Life Vaucasson’s duck. The little writing manikins in the Neufchatel museum. Alife lacks morphogenesis. The shapes really don’t arise naturally from the code. A life lacks homeostasis. Improve DNA-like genomes by fitness proportional reproduction. Fitness = gnarliness? The notion of evolution has been strongly used by computer scientists in attempts to find good programs. Fitness function. Telerobotics (Lifted from my Artificial Life Lab manual.) For many applications, the user might not need for a robot to be fully autonomous. Something like remotely operated hand that you use to handle dangerous materials is like a robot, in that it is a complicated machine which imitates human motions. But a remote hand does not necessarily need to have much of an internal brain, particularly if all it has to do is to copy the motions of your real hand. A device like a remote robot hand is called a telerobot. Radioactive waste is sometimes cleaned up by using telerobots that have video cameras and two robotic arms. The operator of such a telerobot sees what it sees on a video screen, and moves his or her hands within a mechanical harness that send signals to the hands p. 62
Notes for The Lifebox, the Seashell, and the Soul, by Rudy Rucker of the telerobot. I have a feeling that, in the coming decades, telerobotics is going to be a much more important field than pure robotics. People want amplifications of themselves more than they want servants. A telerobot projects an individual's power. Telerobots would be useful for exploration, travel, and sheer voyeurism, and could become a sought-after high-end consumer product But even if telerobots are more commercially important than self-guiding robots, there is still a need for self-guiding robots. Why? Because when you're using a telerobot, you don't want to have to watch the machine every second so that the machine doesn't do something like get run over by a car, nor do you want to worry about the very fine motions of the machine. You want, for instance, to be able to say "walk towards that object" without having to put your legs into a harness and emulate mechanical walking motions---and this means that, just like a true robot, the telerobot will have to know how to move around pretty much on its own. There is an interesting relationship between a-life, virtual reality, robotics, and telerobotics. These four areas fit neatly into the Table 1-3, which is based on two distinctions: firstly, is the device being run by a computer program or by a human mind; and, secondly, is the device a physical machine or a simulated machine? Mind Body Artificial Life Computer Simulated Virtual Reality Human Simulated Robotics Computer Physical Telerobotics Human Physical Table 1-3: Four Kinds of Computer Science Artificial life deals with creatures whose brains are computer programs, and these creatures have simulated bodies that interact in a computer-simulated world. In virtual reality, the world and the bodies are still computer-simulated, but at least some of the creatures in the world are now being directly controlled by human users. In robotics, we deal with real physical machines in the real world that are run by computer programs, while in telerobotics we are looking at real physical machines that are run by human minds. Come to think of it, a human's ordinary life in his or her body could be thought of as an example of telerobotics: a human mind is running a physical body! Code Growth Analogy There is a sense in which computer programs are indeed grown: the executable machine code arises from compiling and assembling the original source code. Here the source code of the program is like the genome, the development environment is like the womb, and the resulting program is like the body. But really we want something more. Walker’s Brag About His Server’s Homeostasis Here’s a quote from an email from my ultrageek pal John Walker, where he’s bragging about the stability of his email server. p. 63
Page 1 and 2:
Notes for The Lifebox, the Seashell
Page 3 and 4:
Page 5 and 6:
Page 7 and 8:
Page 9 and 10:
Page 11 and 12: Notes for The Lifebox, the Seashell
Page 61: Notes for The Lifebox, the Seashell
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
Page 141:
show all

Notes for the Lifebox, the Seashell, and the Soul - Rudy Rucker

Create successful ePaper yourself

Delete template?

Save as template?