3 papers
cond-mat.mtrl-sci2025
Representations of the symmetry groups of infinite crystals
Bachir Bekka, Christian Brouder
We investigate the representations of the symmetry groups of infinite crystals. Crystal symmetries are usually described as the finite symmetry group of a finite crystal with perio…
math.RT2025
Canonical Commutation Relations: A quick proof of the Stone-von Neumann theorem and an extension to general rings
Bachir Bekka
Let be a (not necessary commutative) ring with unit, an integer, and a unitary character of the additive group A pair of unitary representations…
math.RT2024
The -dual space of a semisimple Lie group
Bachir Bekka
Let be a semisimple Lie group. We describe the irreducible representations of by linear isometries on -spaces for with More precisely, we…