释义 |
Standard MapA 2-D Map, also called the Taylor-Greene-Chirikov Map in some of the older literature.
where and are computed mod and is a Positive constant. An analytic estimate of the width of theChaotic zone (Chirikov 1979) finds
 | (3) |
Numerical experiments give and . The value of at which global Chaos occurs has been bounded by various authors. Greene's Method is the most accurate method so far devised.Author | Bound | Fraction | Decimal | Hermann |  |  | 0.029411764 | Italians |  | - | 0.65 | Greene |  | - | 0.971635406 | MacKay and Pearson |  |  | 0.984375000 | Mather |  |  | 1.333333333 |
Fixed Points are found by requiring that
The first gives , so and
 | (6) |
The second requirement gives
 | (7) |
The Fixed Points are therefore and . In order to perform a Linear Stability analysis, take differentials of the variables
In Matrix form,
 | (10) |
The Eigenvalues are found by solving the Characteristic Equation
 | (11) |
so
 | (12) |
 | (13) |
For the Fixed Point ,
The Fixed Point will be stable if Here, that means
 | (15) |
 | (16) |
 | (17) |
 | (18) |
so . For the Fixed Point (0, 0), the Eigenvalues are
If the map is unstable for the larger Eigenvalue, it is unstable. Therefore, examine . We have
 | (20) |
so
 | (21) |
 | (22) |
But , so the second part of the inequality cannot be true. Therefore, the map is unstable at the FixedPoint (0, 0). References
Chirikov, B. V. ``A Universal Instability of Many-Dimensional Oscillator Systems.'' Phys. Rep. 52, 264-379, 1979.
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