Dear All, We are delighted to present the MaPSS Seminar topic of Monday 21/08; please see the abstract below. **This Semester the Seminar will always run on Monday, at 5:00pm in 535A** Following the talk, there will be pizza on offer. Speaker: Nathan Duignan (Sydney University) Title: Regularisation for Singular Points of Planar Vector Fields Abstract: Regularisation for vector fields is concerned with the continuation of solutions through singular points. Many of the core ideas and definitions of regularisation were developed to understand the collision singularities of the n-body problem. Although binary collisions are understood via the Levi-Civita regularisation, there are conjectures about the finite differentiability of nearby orbits of simultaneous binary collisions. This presentation will take a relaxed look at a modern, geometrical understanding of regularisation for singular points of planar vector fields. The primary aim is to introduce the key concepts underpinning the conjecture and provide a mechanism that causes orbits near regularisable singular points to become finitely differentiable. Supervisors, please encourage your students to attend. Thanks, MaPSS Organizers