Vu Hoang Linh, Vietnam National University, Hanoi, Vietnam Joint work with V. Mehrmann (TU Berlin) Title: Spectral intervals for differential-algebraic equations Time: Wednesday, Jun 3, 2009, 11am Place: Building 22, Room 1.28, Campus Neues Palais, Universitaet Potsdam Abstract: This talk is concerned with the Lyapunov and exponential dichotomy spectral theory which is extended from ordinary differential equations (ODEs) to nonautonomous differential-algebraic equations (DAEs). By using orthogonal changes of variables, the original DAE system is transformed into appropriate condensed forms, for which concepts such as Lyapunov exponents, Bohl exponents, exponential dichotomy and spectral intervals of various kinds can be analyzed via the resulting underlying ODE. Some essential differences between the spectral theory for ODEs and that for DAEs are pointed out. I will also discuss how numerical methods for computing the spectral intervals associated with Lyapunov and Sacker-Sell (exponential dichotomy) spectra can be extended from those methods proposed for ODEs. Some numerical examples are presented to illustrate the theoretical results.