Erik Christensen Department of Mathematical Sciences I am a retired lecturer in mathematics at the University of Copenhagen. My research interests are operator algebras and its applications to mathematical physics and noncommutative geometry. For a more detailed description of the research done, you may consult my CV and my list of publications via the links below. CV: Publications: Google Scholar profile: ResearchGate profile: Groups: Non-Commutative Geometry group Centre for Symmetry and Deformation Contact Information: Erik Christensen Department of Mathematical Sciences Universitetsparken 5 2100 Copenhagen Ø Denmark Home address: Ganlosevej 37 DK 3520 Farum Denmark Email: echris@math.ku.dk Mobile phone: 2636 2957.