Chua's Circuit is one of a few physical systems for which the presence of chaos has been observed experimentally, verified by computer simulations, and proven mathematically.
It can also be used to generate musical signals and compositions. (Hear also the radio report by Bob Hirshon, "Bassoon Circuit", AAAS Science Update, Mutual Broadcasting System, Nov. 1993).
This document summarizes a collaboration between members of the Center for Complex Systems Research (CCSR) of the Beckman Institute (BI) and the Physics Department of the University of Illinois at Urbana Champaign (UIUC) and of the Virtual Environment Group (VEG) of the National Center for Supercomputing Applications (NCSA) .
Chua's circuit contains several electronic components (resistors, capacitors, inductor) whose properties determine the observed dynamical behavior and attractor. For instance if we steadily decrease the value of the resistor R, we observe the following bifurcation diagram:
If we use the output voltages of the circuit as input to a loudspeaker, we can represent the same bifurcation sequence sonically, (second example).
The ordinary differential equations , that describe the dynamics of the Chua Circuit are given in its physical variables and parameters. The dimensionless form of the equations are typically used for theoretical/computational analysis. Besides the display of the timeseries of components of solutions or state space representations
The sonic presentation of signals from Chua's Circuit produces a variety of sounds, most of them are either very noisy or relatively uninteresting pure tones. For certain parameter ranges, however, for example some with asymmetric break-points, one can observe interesting sounds, some of which are bassoon-like. The Chua oscillator (both the analog hardware and the digital simulation) has also been the dominant instrument in a piece of modern music, anti-Odysseus, the irreversibility of time [1].
The dynamic structure that is present in the chaos of Chua's oscillator
can be displayed in a multitude of graphical and sonic representations.
The variation in the sensitivity to initial conditions (which can be
seen as a measure for the local degree of Chaos) can be illustrated with
the help of
recurrence diagrams.
Besides control of individual parameters by sliders, several graphical interfaces have been
developed (e.g. for the NeXT (left) and the Silicon Graphics Iris (right,
image configuration courtesy of Insook Choi)). 
....
At the SIGGRAPH '94 conference held July 25 - 29, 1994, at the Orlando Convention Center in Orlando, Florida, the Virtual Environment Group (VEG) of the National Center for Supercomputing Applications (NCSA) presented a demonstration of interactive graphical and sonic representations of the Chua oscillator in the Virtual Reality rOOM (VROOM) exhibit. (See also here for a description of the artistic aspects of the display.) The Chua oscillator in the CAVE can be simulated on a SGI platform (tarred, gzipped, 4.29MB, uncompressed 9.9MB)
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