Special Session 162: Computer-Assisted Proofs in Dynamical Systems

Validated matrix multiplication transform for orthogonal polynomials with applications to computer-assisted proofs for PDEs
Jonathan Jaquette
New Jersey Institute of Technology
USA
Co-Author(s):    Matthieu Cadiot, Jonathan Jaquette, Jean-Philippe Lessard, Akitoshi Takayasu
Abstract:
In this talk, we develop computational tools related to the rigorous computational analysis of nonlinear PDEs posed on geometries such as disks and cylinders. First, we introduce a validated Matrix Multiplication Transform (MMT) algorithm, analogous to the discrete Fourier transform, which offers a reliable framework for evaluating nonlinearities in spectral methods while effectively mitigating challenges associated with rounding errors. Second, we examine the Zernike polynomials, a spectral basis well-suited for problems on the disk, and highlight their essential properties. We further demonstrate how the MMT approach can be effectively employed to compute the product of truncated Zernike series, ensuring both accuracy and efficiency. Finally, we combine the MMT framework and Zernike series to construct computer-assisted proofs that establish the existence of solutions to two distinct nonlinear elliptic PDEs on the disk.