The non-commutative geometry of defects
John Barrett (University of Nottingham)
Tuesday 26th November, 2019 14:00-15:00 Maths 311B
A diagrammatic calculus is introduced for non-commutative geometry in the form of a finite real spectral triple. This calculus provides a quantum invariant of surfaces with spin structure and defect lines. There are two sorts of defect lines, those labelled with the Hilbert space of the non-commutative geometry and those labelled with data that determine a Dirac operator. The axioms of non-commutative geometry follow from the topological properties of defect lines.