Colloquium Series

Fall 2026

September 18, 2026

Tim Atherton, Tufts University

Topic: Shapeshifting, elasticity and quasiconformal geometry in liquid crystals
Time: 3:00-4:00 pm
Location: JCC 270
Reception: JCC 535
Abstract: Shape, elasticity, and geometry are deeply interconnected in the physics of soft materials. In this talk, I’ll present two projects from my group that explore these connections from different mathematical perspectives.

The first is a long-running effort to simulate shape-changing materials using finite element methods. Rather than deriving and solving the associated Euler–Lagrange equations, we formulate these problems directly as optimization problems: discretize the energy, then minimize it. This approach has led us to develop morpho, a programmable environment for computational soft-matter physics created through a collaboration among physicists, mathematicians, and computer scientists.

The second project uses ideas from complex analysis to understand elastic anisotropy in nematic liquid crystals. I will show that planar elastic anisotropy possesses a hidden geometric structure: it defines a spatially rotating anisotropic metric whose natural language is quasiconformal mapping. Using this framework, we can construct explicit defect configurations and reveal an underlying geometry that is largely hidden in the conventional formulation of nematic elasticity.

Together, these projects illustrate how changing the mathematical representation of a physical problem, through optimization in one case and geometry in the other, can expose new structure and suggest new tools for studying shape change and complex media more broadly.