Fast algorithms in cryo-electron microscopy and beyond
Owen Hall 101
Speaker: Oscar Mickelin
This talk presents a number of numerical problems that arise from a computational imaging technique known as cryo-electron microscopy. This technique solves the non-linear inverse problem of recovering the three-dimensional structures of molecules from randomly oriented tomographic projection images, with important applications in biology.We will focus on a fast and provably accurate algorithm to expand discretized image-valued data into the basis of eigenfunctions of the Dirichlet Laplacian on the unit disk. For LxL images, the algorithm computes O(L^2) basis coefficients in complexity O(L^2 log(L)), for a fixed accuracy, which is significantly lower than brute-force approaches. We will also discuss a fast algorithm to perform rotationally invariant covariance estimation of cryo-EM images, and extensions to three-dimensional basis functions. Read more.