Explore a 46-minute lecture on spectral approximation of transfer operators, delivered by Oscar Bandtlow as part of the Hausdorff Trimester Program "Dynamics: Topology and Numbers" conference. Delve into the challenge of approximating spectral data of transfer operators, particularly those relevant to number theory applications. Learn about an easily implementable Galerkin-type method using Lagrange–Chebyshev interpolation and its convergence properties. Examine topics such as projection methods, Ulam methods, a priori error estimates, and convergence results for analytic and smooth cases. Discover the application of these concepts to resonances of Schottky surfaces and gain insights into the historical context of transfer operators in mathematics.