Historical and other Remarks on Hidden Symmetries
  Apart from a few remarks on lattice systems with global or gauge symmetries, most of this talk is devoted to some interesting ancient examples of symmetries and their breakdowns in elasticity theory and hydrodynamics. Since Galois Theory is in many ways the origin of group theory as a tool to analyse (hidden) symmetries, a brief review of this profound mathematical theory is also given. 
Norbert Straumann (University of Zuerich)