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Chaos, and what to do about it (2018)

chaosbook.org

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Re: Chaos, and what to do about it (2018)

#21

Is "chaos" simply the point where humans lose the ability to keep track of things, or is there a more ..universal definition?

No universally accepted mathematical definition of chaos exists. My guess we only at the beginning of understanding it and more theories will emerge.

Re: Chaos, and what to do about it (2018)

#22
post #3

I thought this was going to be about the popsci book with a similar name: Chaos: Making a New Science https://www.goodreads.com/book/show/64582.Chaos

Ah, I loved that book as a teen. Unfortunately I lent it to an ex whom I broke up with before she had returned it and never spoken with eversince. I fondly remember tinkering with a PHP program (that was the only language I knew at the time ¯\_(ツ)_/¯) to draw the bifurcation diagram of the logistic map which then I used as my desktop background.

:) I wrote a couple of tables on Excel v1 that was running on the original Mackintosh we had at home to play around with the same equations.

Re: Chaos, and what to do about it (2018)

#23

Is "chaos" simply the point where humans lose the ability to keep track of things, or is there a more ..universal definition?

[deterministic] Chaos: When the present determines the future, but the approximate present does not approximately determine the future.

Edward Lorenz

Re: Chaos, and what to do about it (2018)

#24

Cvitanovic's book, and apparently Cvitanovic himself (I've traded an email or two, but he's friends of friends -and seems to always make a big impression in person) is amazing. It's been around in some form or other since I was wrapping up my ph.d. thesis in a related subject, and I remember being mad as hell it didn't exist when I started as it had the most understandable explanations of the Gutzwiller trace formula…

Yes, his book and Ozorio de Almeida’s are the best I’ve found on the subject

Re: Chaos, and what to do about it (2018)

#25
post #14

Is "chaos" simply the point where humans lose the ability to keep track of things, or is there a more ..universal definition?

The ability of an observer to keep track of things is not relevant, and even completely computable things like cellular automata can be chaotic [1]. The common definition of chaotic dynamics [2] requires the system to be sensitive to initial conditions, mix the state space, and have dense periodic orbits. [1] https://en.wikipedia.org/wiki/Rule_30#Chaos . [2] https://en.wikipedia.org/wiki/Chaos_theory#Chaotic_dynamics

Thanks.

I found this to be the most intuitive example (for myself to grok):

https://en.wikipedia.org/wiki/Double_pendulum#/media/File:De...

Re: Chaos, and what to do about it (2018)

#27
post #14

Earlier quoted context omitted.

The ability of an observer to keep track of things is not relevant, and even completely computable things like cellular automata can be chaotic [1]. The common definition of chaotic dynamics [2] requires the system to be sensitive to initial conditions, mix the state space, and have dense periodic orbits. [1] https://en.wikipedia.org/wiki/Rule_30#Chaos . [2] https://en.wikipedia.org/wiki/Chaos_theory#Chaotic_dynamics

Thanks. I found this to be the most intuitive example (for myself to grok): https://en.wikipedia.org/wiki/Double_pendulum#/media/File:De...

Made me think of: https://en.wikipedia.org/wiki/Three-body_problem
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