APDE: Seminars

Seminars in Applied and Computational Analysis

Particles in Membranes

The interplay of curvature and particles diffusing in biological membranes is responsible for organizing and shaping the membrane and gives rise to a variety of cellular functions. Hybrid models combining a continuum representation of the membrane with discrete, highly coarse grained descriptions of particles have a long history in physics, while mathematical analysis is still in its infancy. We present a hierarchy of variational formulations of existing hybrid models, where the coupling of particles and membrane is formulated in terms of linear constraints to the minimization of the Canham–Helfrich energy of the membrane. Utilizing concepts from shape calculus, we derive a numerically feasible representation of the derivative of the minimal Canham–Helfrich energy for given particle positions with respect to the particle positions. This representation is applied in numerical investigations of the clustering behaviour of BAR domains and paves the way to Langevin dynamics of particles in membranes.

This is joint work with C.M. Elliott, C. Gräser and T. Kies

Title to be confirmed

Abstract not available

This is a joint ACA-GAPDE seminar

An Introduction to Randomized Algorithms for Matrix Computations

The emergence of massive data sets, over the past twenty or so years, has lead to the development of Randomized Numerical Linear Algebra. Fast and accurate randomized matrix algorithms are being designed for applications in machine learning, population genomics, astronomy, nuclear engineering, and optimal experimental design.

We give a flavour of randomized algorithms for the solution of least squares/regression problems. Along the way we illustrate important concepts from numerical analysis (conditioning and pre-conditioning), probability (concentration inequalities), and statistics (sampling and leverage scores).

This is a joint ACA–CCIMI seminar



Graduate Seminars (WE 15:00, MR5)