[HN Gopher] Symmetry in Chaos ___________________________________________________________________ Symmetry in Chaos Author : lioeters Score : 162 points Date : 2023-08-13 12:42 UTC (10 hours ago) (HTM) web link (paulbourke.net) (TXT) w3m dump (paulbourke.net) | progrus wrote: | Wow this is cool. I thought it was was going to be the latest | cosmology from the stringcels. | ykonstant wrote: | Those are gorgeous; I would enjoy some explanation on how the | authors came to investigate these particular recurrences. | Wolfenstein98k wrote: | Can't be read on mobile (Brave browser) | alkyon wrote: | Horizontally only;) But the article is well worth it. | [deleted] | Horffupolde wrote: | I would argue that position-symmetry is not unexpected in a | chaotic system. Symmetry means that one of your dimensions is | redundant. | ironSkillet wrote: | Why does it mean that? | jfoutz wrote: | I'm not an expert, but think about linear algebra. | | you can write each dimension value in terms of time t(a) -> | t(b) | | x = sin(t) y = 2cos(t) | | or whatever. if there is a symmetry, one of those equations | should cancel out. | | another way to look at it is, if you can always get x, and | know y "for free", or the other way around, then x and y | aren't really independent. there's some other thing, like | sqrt(t) that's generating both values. | [deleted] | [deleted] | defrost wrote: | _Marty Golubitsky 's Homepage_ https://www.asc.ohio- | state.edu/golubitsky.4/ | | Books by same: https://www.asc.ohio- | state.edu/golubitsky.4/mgbooks.html | | https://en.wikipedia.org/wiki/Marty_Golubitsky | | _Fearful Symmetry: Is God a Geometer?_ Ian Stewart + Martin | Golubitsky | | is a good read, Ian Stewart is well known to UK recreational math | fans and frequently hosts STEM material on th BBC. | | https://www.goodreads.com/en/book/show/1651085 | This sequel to the bestselling *Does God Play Dice?* will open | your eyes to the broken symmetries that lie all around you, from | the shapes of clouds to the drops of dew on a spider's web, from | centipedes to corn circles. It will take you to the farthest | reaches of the universe and bring you face-to-face with some of | the deepest questions of modern physics. | euroderf wrote: | Please stop feeding drugs to my pet Spirograph. | [deleted] | cossatot wrote: | Does anyone know where to find some code examples in which RGB | images are generated from the equations? I don't really | understand how the mathematical solution is translated into a | raster/pixel image and what the colors correspond to. But I would | love to start making playing with these. | IAmGraydon wrote: | It's right there in the article: | | > The images here are generated by iterating the series | typically 1,000 million times. This is performed in two passes, | the first pass with many fewer iterations is used to find the | bounds of the attractor on the complex plane, the second pass | actually "draws" the attractor points. The process of drawing | involves treating the bounded region of the complex plane as a | 2D histogram, each time the series passes through a pixel | region on the plane the histogram at that location is | incremented. One might imagine the 2D histogram as a height | field, a larger values at a point indicate that the complex | series passed through that pixel more often than a point with a | smaller value. At the end of the process the histogram is | mapped onto colours depending on the histogram values, there | are many ways to do this based on aesthetic grounds. | viesauvage wrote: | > Chaos | | I think there's more like a semantic slipping over this term, so | that chaos ends up passing for another kind of order. | | Chaos is chaos. It's a bunch of really random stuff happening | within an undefined, undetermined space, with randomly variable | means. Like a landslide is chaos. The arrangement of stuff post- | landslide will be a complete, incoherent, unpredictable mess. | | Today's normie "scientific" definition of "chaos" is what stands | for "weird" or more accurately, ASYMMETRICAL. | | More philosophy, please. | DonHopkins wrote: | No, Chaos is the enemy of Control! | | https://www.youtube.com/watch?v=3KF5NfzmIvU | | "This is KAOS. We don't shoosh here!" | talkingtab wrote: | "A new kind of Science". Wolfram. Don't leave home without it. | | Seriously though. We talk about AI, but In My Opinion, the most | powerful and interesting game changer is "Complex Adaptive | Systems". I call them gestalts - the sum is greater than the | parts because of _how_ the parts interact to produce behaviors. | Gestalts are all around us and we seem bizarrely unaware of them. | Do you have some money? That means you are participating in a | complex adaptive system or gestalt. Got cells? Perhaps you are a | gestalt? Are you self aware? Does that mean you are a self aware | gestalt, participating in other gestalts. Etc. | | The difficult question is whether you (yes you personally) can | build a gestalt. Can you take some pieces - entities - give them | a set of rules and get them to do some accomplish a purpose. That | is the problem Wolfram was asking | | The RIP router is a defunct example that has all the pieces. | Entities + Ability to interact + rules => function. | | Oh, and don't forget to vote. | ilaksh wrote: | In other words, metasystems via metasystem transitions. | | See Cosmic Evolutionary Philosophy and a Dialectical Approach | to Technological Singularity | | https://www.semanticscholar.org/paper/Cosmic-Evolutionary-Ph... | fellowmartian wrote: | I used to believe in the "sum is greater than the parts" bit, | in the context of emergence etc, but then I'd realized it's at | odds with basic information theory: where does the information | go? what computes these behaviors? To me the answer is pretty | clear: you're outsourcing some of your storage and compute into | the environment. Without a suitable substrate none of this | would be possible. | defrost wrote: | http://bactra.org/reviews/wolfram/ | VHRanger wrote: | Thanks, whenever Wolframs stuff comes up that bactra piece | and this one: | | singlelunch.com/2020/04/23/why-stephen-wolframs-research- | program-is-a-dead-end | | Should be mentioned since people should have the context that | he's considered a crank byoat everyone in the communities | he's doing research in | abetusk wrote: | These are awesome, but it would be nice to understand, even at | some heuristic level, why they're periodic with the period they | do have. | | Alternatively, what is a change to a completely periodic orbit to | chaos with the same "periodic symmetry" that gives some | enlightenment of where the chaos is being inserted and why it | isn't destroying the periodic orbit. | | Does anyone have an idea of whats' going on, or references that I | can look at? | lanstin wrote: | These systems do not have periodic orbits they have symmetric | strange attractors. | | So tracing a particle thru these systems will not result in | periodicity but will trace out these symmetric structures. It | is unclear from the website if these are proven symmetries or | observed. | | A good book that is a bit more technical than Gleick (which I | found not wrong in the details it does have) is "Introduction | to Applied Nonlinear Dynamical Systems and Chaos" by Stephen | Wiggins. It requires basic under grad maths but is a graduate | text in that very close reading is needed to follow. The first | 17 chapters are intended as a semester class. | dmbche wrote: | James Gleick's "Chaos: Making a new science" will answer your | questions and is a fun read! | abetusk wrote: | Could you point to the chapter or page? | dmbche wrote: | I have a hard time pointing you somewhere, I think you | should start with the first chapter and see from there, | it's a good primer. | abetusk wrote: | I've skimmed Gleick's book before and my feeling is that | it's a high level overview of the subject without much | content in either explaining the underlying math, the | motivation behind it or giving some deeper insight into | the subject, at least at a level that I would consider | valuable. | | I'm probably being too pejorative, but these books (like | GEB or the like) are something I consider "feel good" | books that give the illusion of understanding rather than | any real insight. They're great for motivating people to | learn more and popularizing mathematics as something to | be valued but I find them to be very bad for actual | understanding. As a litmus test, can you name any | prediction that people can make after reading the book? | Are there any falsifiable experiments that people can | run? | | Contrast this with John Baez's post on roots of | polynomials with integer roots [0]. Not only are there | pretty pictures but there's an in depth explanation of | what the structures are and how they show up (IFS, | connectivity, etc.). | | Something along the line of Baez's treatment of roots of | polynomials with integer coefficients is what I was | looking for on how these structures show up in these | chaotic systems. | | [0] https://math.ucr.edu/home/baez/roots/ | | EDIT: "GEB" not "GED" | dmbche wrote: | It's been a while, but I remember many experiments being | presented in Gleick's book ( The double pendulum being a | chaotic system, or the paper showing how it was | impossible to predict the distance between two points in | a structure after steching and folding it) | | The gist being that some systems are much more sensitive | than others to initial variables - and these are what we | call chaotic. | | For the double pendulum, for example, you try to release | the pendulum from the same point, with 0 force - no | matter how precise you are, there will be variability in | the position, air pressure, temperature, turbulence and | whatnot that will induce a small variability. This is | unavoidable - but in chaotic systems, the effects are | impossible to predict i.e. the pendulum always swings | differently. | | The pretty pictures come from what are called "strange | attractors" which are all dependent on the system you are | studying because they flow from the systems attributes. | It's not black magic - a simple example from the book is | that heat distribution can be chaotic in liquid systems | like coffee cups - so it's impossible to predict the | precise temperature inside any cup given it's initial | state, but we all know it's cold after an hour. This is | not the best explanation for this concept, I believe the | last third of the book is on the subject. | | Hopefully this could help out. | | Edit: if you were to plot position of the pendulum for | many thousands of drops, some patterns will emerge - the | pendulum moves in a "finite" set of positions, because it | physically can't go in some positions after some others, | for example. Or it will have the same period in rising | and falling in all graphs from having close to the same | initial energy but not orientation. | | So it'll look neat - but it doesn't necessarily mean | much. | abetusk wrote: | OK, that's fair, I was being too critical of Gleick's | book. | | Even so, this doesn't really get at the high level | symmetry. Gleick's book might give some motivation for | the chaotic points being restricted to a compact domain | (space? manifold? area/volume?) but I don't see how to | make the leap to the highly structured gross level | symmetry in the OP. | dmbche wrote: | I think you might want to look into the Mandelbrot and | Julia set, and things like Kochs Snowflake, as these are | purely mathematical systems like in OP - this is one part | of the book I didn't integrate as well, you might be | satisfied by the book - but OP also lists some references | on the symmetry of chaotic systems, maybe that's a better | way forward! | abetusk wrote: | See alimw's response [0]. | | [0] https://news.ycombinator.com/item?id=37114898 | alimw wrote: | All of these are aperiodic; it says as much in the first | paragraph. Are you talking about the rotational symmetry? | abetusk wrote: | Yes, the high level rotational symmetry. There's some gross | level structure that's preserved while the individual points | are (presumably) completely aperiodic/chaotic. | | What's some insight into the gross level symmetric features | appearing? How do you convert something that's completely | periodic to an aperiodic/chaotic system with gross level | periodic structure? What are the operations that allow the | gross level periodic structure to remain while making the | fine grained structure aperiodic/chaotic? | alimw wrote: | They iterate f where f(z) = (a0 + a1 z z + a2 Re(zn) + a3 | i) z + a4 zn-1. You can easily check that f(z exp(i 2 p / | n)) = exp(i 2 p / n) f(z). | bannedbybros wrote: | [dead] | DonHopkins wrote: | Also check out Jim "Chaos" Crutchfield's work, and the | mesmerizing video feedback he made with his analog video | processing computer that he built at the University of | California, Santa Cruz for his Ph.D. in physics in 1984. | | Jim Crutchfield | | https://en.wikipedia.org/wiki/James_P._Crutchfield | | https://csc.ucdavis.edu/~chaos/index.html | | Space-Time Dynamics in Video Feedback | | https://www.youtube.com/watch?v=B4Kn3djJMCE | | A film by Jim Crutchfield, Entropy Productions, Santa Cruz | (1984). Original U-matic video transferred to digital video. 16 | minutes. | | See: | | https://csc.ucdavis.edu/~chaos/chaos/films.htm | | Citation: J. P. Crutchfield, "Space-Time Dynamics in Video | Feedback". Physica 10D (1984) 229-245. | | https://csc.ucdavis.edu/~chaos/chaos/pubs/stdvf-title.html | | Chaotic Attractors of Driven Oscillators | | https://www.youtube.com/watch?v=Sq8Vu40Bw1g | | A film by Jim Crutchfield, Entropy Productions, Santa Cruz | (1982). Original 16mm transferred to U-matic video and then to | digital video. 13 minutes. | | In 2022, Crutchfield and his graduate student Kyle Ray described | a way to bring the heat production of conventional circuits below | the theoretical limit of Landauer's principle by encoding | information not as pulses of charge but in the momentum of moving | particles. | | https://www.scientificamerican.com/article/lsquo-momentum-co... | | While a graduate student, Crutchfield and students from the | University of California, Santa Cruz (including Doyne Farmer) | built a series of computers that were capable of calculating the | motion of a moving roulette ball, predicting which numbers could | be excluded from the outcome: | | The Eudaemonic Pie / Newton's Casino: The Bizarre True Story of | How a Band of Physicists and Computer Wizards Took on Las Vegas | | https://archive.org/details/eudaemonicpie00bass_0/mode/2up | [deleted] | HDevo wrote: | Paul Bourke's website is great; don't forget to check his other | articles! | | Over 10 years ago, it inspired me to play with strange | attractors, which eventually ended with me writing | https://github.com/chaoskit/chaoskit. | | It was fun and I learned a lot, but it's definitely a deep rabbit | hole. I've moved on since then. | jes wrote: | This reminds me of an Alan Watt's talk on alternating levels of | order and chaos in nature. | passion__desire wrote: | To add some spice to your observation. I read somewhere that | "This statement is false" can act as a oscillator, a "clock" | going tick-tock, at the deepest level of reality. | jes wrote: | Please say more! | andybak wrote: | Ok. I need to know more. | passion__desire wrote: | Well actually, it was a comment on a blogpost (I don't know | what it was about). It said since if our world is a | simulation, then it needs a computer to run on. And every | computer needs a clock. So this statement changing its | truth value could act as a clock. | sandman1906 wrote: | Do you remember the title of it? | pluijzer wrote: | Web of Life | | Here is the youtube video and transcript. I think the parent | poster refered to section IV, around 19:20 in the video. | | https://www.organism.earth/library/document/out-of-your- | mind... | jes wrote: | Perfect. Appreciate the ref. | andybak wrote: | On the theme of "Unexpected Alan Watts" I'd like to recommend | the game "Everything" which after a slightly bizarre start | develops into a "achieve subgoal, get an Alan Watts audio clip | as a reward" gameplay loop. It's fantastic. | jes wrote: | Will check it out! Ty! ___________________________________________________________________ (page generated 2023-08-13 23:00 UTC)