Quasicrystals and cohomology

par Johannes Kellendonk

mercredi 18 mars 2026, 12:15 → 14:15 Europe/Paris

Fokko du Cloux (Braconnier)

 A quasicrystal is an aperiodic material whose diffraction measure pure point.
Its structure can be modelled by an aperiodic tiling. The fact that the diffraction measure is pure point is a sign that the material is long range ordered. Another sign of long range order is exact regularity. Following work of Lorenzo Sadun, I will explain what this means and how it is related to the cohomology of the tiling.