User blogs

Exploring Quantum, Classical and Semi-classical Chaos in the Stadium Billiard (by Chris King)

Abstract: This paper explores quantum and classical chaos in the stadium billiard using Matlab simulations to investigate the behavior of wave functions in the stadium and the corresponding classical orbits believed to underlie wave function scarring. The simulations use three complementary methods. The quantum wave functions are modeled using a cellular automaton (CA) simulating a Hamiltonian wave function with discrete (square pixel) boundary conditions approaching the stadium in the classical limit. The classical orbits are computed by solving the reflection equations at the classical boundary thus giving direct insights into the wave functions and eigenstates of the quantum stadium. Finally a simplified semi-classical algorithm is developed to show the comparison between this and the quantum wave function method. http://prespacetime.com/index.php/pst/article/view/351

Exploding the Dark Heart of Chaos: Part I, II & III (by Chris King)

Abstract: This paper, with its associated graphical software and movies, is an investigation of the universality of the cardioid at the centre of the cyclone of chaotic discrete dynamics, the quadratic ‘heart’ forming the main body of the classic Mandelbrot set. Using techniques investigating and exploring the continuity, bifurcations and explosions in its related Julia sets, we demonstrate its universality across a wide spread of analytic functions of a complex variable, extending from the classical quadratic, through higher polynomials and rational functions, to transcendental functions and their compositions. The approach leads to some interesting and provocative results, including decoding dendritic island periodicities, and multiple critical point analysis, leading to layered Mandelbrot set ‘parameter planes’, and intriguing issues of critical point sensitivity in the irregular structures in the Mariana trenches of the more complex functions.

Part I of this article includes: 1. Real ‘Boom and Bust’ Origins of the Dark Heart; 2. Illuminating the Writhing Dark Heart of Complexity; 3. The Dark Heart’s Magic Numerology; and 4. A Heart is only Half a Hamburger: Degenerate Critical Points. http://prespacetime.com/index.php/pst/article/view/352

Part II of this article includes: 5. Hearts Layered as Onions of Complexity: Generalizing to Higher Polynomials; 6. The Dark Heart of Division: Rational Functions and Newton’s Method; 7. Transcendent Chaos out of Quadratic Disorder; and 8: Falling into the Heart of Deep Transcendental Variation. http://prespacetime.com/index.php/pst/article/view/353

Part III of this article includes: 9. Getting to the Heart of the Riemann Zeta Function; Conclusion; Software and Demonstrations; Appendix 1: Combined Methods of Depicting Julia Sets and Parameter Planes; and Appendix 2: Ray Tracing Hypercomplex and Multi-dimensional Chaotic Iterations. http://prespacetime.com/index.php/pst/article/view/354