Equivariance and partial observations in Koopman operator theory for partial differential equations

التفاصيل البيبلوغرافية
العنوان: Equivariance and partial observations in Koopman operator theory for partial differential equations
المؤلفون: Peitz, Sebastian, Harder, Hans, Nüske, Feliks, Philipp, Friedrich, Schaller, Manuel, Worthmann, Karl
سنة النشر: 2023
المجموعة: Computer Science
Mathematics
مصطلحات موضوعية: Mathematics - Dynamical Systems, Computer Science - Machine Learning
الوصف: The Koopman operator has become an essential tool for data-driven analysis, prediction and control of complex systems. The main reason is the enormous potential of identifying linear function space representations of nonlinear dynamics from measurements. This equally applies to ordinary, stochastic, and partial differential equations (PDEs). Until now, with a few exceptions only, the PDE case is mostly treated rather superficially, and the specific structure of the underlying dynamics is largely ignored. In this paper, we show that symmetries in the system dynamics can be carried over to the Koopman operator, which allows us to massively increase the model efficacy. Moreover, the situation where we only have access to partial observations (i.e., measurements, as is very common for experimental data) has not been treated to its full extent, either. Moreover, we address the highly-relevant case where we cannot measure the full state, such that alternative approaches such as delay coordinates have to be considered. We derive rigorous statements on the required number of observables in this situation, based on embedding theory. We present numerical evidence using various numerical examples including the wave equation and the Kuramoto-Sivashinsky equation.
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2307.15325
رقم الأكسشن: edsarx.2307.15325
قاعدة البيانات: arXiv