Accelerating the Dimer Algorithm for Computing Saddle Points

SCAIM Seminar
March 25, 2014 7:30 pm

Speaker:  Christoph Ortner, University of Warwick

URL for Speaker:

Location:  ESB 4133

Intended Audience:  Public

The dimer method is a simple hessian-free algorithm for computing index-1 saddles. In this talk, I will review and analyze a few variants of this algorithm, focusing on some improvements to its efficiency, in particular adding preconditioning capabilities and line-search based on a local merit function. I will demonstrate the efficiency of the new variant on a range of applications from academic toy problems, an atomistic problem and a PDE problem.

Despite these new improvements, we can currently give no global convergence guarantee. Indeed, we can construct counterexamples to global convergence. I will conclude my talk by explaining some of the difficulties we encountered.