SYLLABUS FOR

 

                                     PHYS460: NONLINEAR SYSTEMS AND CHAOS

 

Instructor: Paul Fahey   , Room 279 St. Thomas Hall       email: faheyp1@scranton.edu

 

Credits: three

 

Course Description:

 

            This course develops the equations that describe several important nonlinear systems in mechanics and in electronics and then develops the solutions.  Concepts such as limit cycles, chaotic attractors, hysteresis, stability and phase space will be defined and used to understand complex systems.  Classically important oscillators such as the Duffing oscillator, the van der Pol oscillator and the Lorenz equations will be solved at several different levels of approximation with several ODE solvers. Chaos, bifurcations, the routes to chaos, chaotic maps and the correspondence between maps and Poincare sections of physical systems will be studied.  The output spectra of nonlinear systems in general will be discussed and methods for calculating the amplitudes of harmonics, sub-harmonics and intermodulation distortion products will be developed.  It is anticipated that the application of all of the above to the nonlinear mechanical response of the inner ear will cap this course.  The software packages MAPLE and MATLAB will be used throughout the course in the solution development and display.  CHAOTIC DYNAMIC WORKBENCH and CHAOS DEMONSTRATIONS will be used to develop some concepts and to experiment with model nonlinear systems. 

 

Texts: The required/primary text is from Nonlinear Dynamics and Chaos by Steven H. Strogatz (Addison-Wesley, 1994).  Supplementing the primary text are: Chaos and Nonlinear Dynamics by Robert C. Hilborn (Oxford University Press, 1994); Chaotic Dynamics of Nonlinear Systems by S. Neil Rasband (John Wiley and Sons, 1990); Nonlinear Oscillations by Peter Hagedorn (Clarendon Press/Oxford, 1988); Nonlinear Physics by R.Z. Sagdeev, D.A. Usikov and G.M. Zaslavsky (Harwood Academic Publishers, 1988); Nonlinear Oscillations in Physical Systems by C. Hayashi (reprinted from 1964 by Princeton University Press, 1985).  Also, there is some light reading that will be required:  SYNC: The Emerging Science of Spontaneous Order  by Steven Strogatz (Hyperon, 2003).

 

            The software documentation of MAPLE, MATLAB, CHAOS DEMONSTRATIONS and CHAOTIC DYNAMICS WORKBENCH will also be used by way of reference.  Other software will be available such as CHAOS FOR THE CLASSROOM.

 

Prerequisite: Calculus and elementary physics.

 

Grading:  Grades will be based upon both individual and team assignments/projects (60%) assigned as the course proceeds.  The projects will be graded on both clarity of written expression (where appropriate) and mathematical and scientific accuracy.  About 2/3 of the way through the course students will submit a 300 to 400 word research topic proposal.  Three weeks before finals students will submit a 3,500 to 4,500 word first draft.  This will be corrected and resubmitted as a second draft.  After corrections a final draft will be submitted during finals weeks.  The paper will be written in the style of a scientific paper and the paper must use the theory developed as the course proceeds.. This paper will comprise 40% of the grade.

 

Topics:  The topics mostly follow the order of the primary text.  They are:

 

            1. Outline of the course and familiarization with the texts and with the software.

 

            2.  Flows on the line.

 

3.      Bifurcations.

 

4.      Flows on the circle.

 

5.      Linear systems.

 

6.      Limit cycle.

 

7.      Duffing oscillator solved with approximations and with numerical ODE solvers (after most of the references above).  Multiple-valued solutions and hysteresis (after the book by Hayashi) and subharmonics.

 

8.      Van der Pol oscillator and limit cycles and phase locking.

 

9.      Lorenz oscillations and the onset of chaos with examples of chaotic transients, intermittency, and period doubling.

 

10.  Bifurcations revisited.

 

11.  One-dimensional maps.

 

12.  Strange attractors.

 

13.  Nonlinear input-output functions and spectra.

 

14.  Nonlinear response of the inner ear and it many manifestations.  There is considerable recent research activity on the role of Hopf oscillations in setting hearing sensitivity.