USNA Mathematics Department seminar

The talks for the academic year 1998-99 are held in Chauvenet 116 at 3:45 pm unless otherwise stated.

 

Speaker:

Erik Bollt


USNA

 

Title:

On the Inverse Frobenius-Perron Problem: Global Stabilization of Arbitrary Invariant Measures

 

Abstract: Alternative to the popular OGY and targeting techniques of controlling chaos is the statistical based inverse Frobenius-Perron Problem (IFPP). In our approach, we reduce the question of stabilizing an arbitrary invariant measure, to the question of whether or not a corresponding hyperplane intersects a unit hyperbox. Based on this simple observation, we introduce a straight forward matrix-based control algorithm, and we assert several easily tested controllability theorems. A major requirement of our transition matrix approach, is our ability to approximate the dynamical system by a stochastic matrix using the Ulam conjecture, and then our ability to pass from the modified stochastic matrix back to an appropriate and nearby dynamical system, which we call the inverse Ulam problem (IUP). We present here a new class of piecewise affine transformations, generalizing the Baker's maps for an arbitrary grammatical symbol dynamics, designed to solve the IUP.

In this talk, we will give background information, including discussion of action of a dynamical system on a distribution ensemble of initial condition, whose long-term distribution defines ``observed statistics." This action on distributions is defined by an associated Frobenius-Perron operator on L^1 distributions, and the Koopman operator, the dual operator on measures. Several examples will be given in the more easily accessible one-dimensional case. We will also discuss the so-called Ulam conjecture, and its relationship to our problem.

 

Time: Wednesday, Nov 4, 1998

 

Reception at 3:30 in the common room on the 3rd floor of Chauvenet Hall.