38 citations · 70 across the 12 of their papers we have counts for
12 papers
Algebras of Fractions and Strict Positivstellensätze for *-Algebras
Konrad Schmuedgen
In this paper we investigate a *-algebra $\cX$ of fractions associated with a unital complex *-algebra $\cA$. The algebra $\cX$ and its Hilbert space representations are used to pr…
Non-commutative Real Algebraic Geometry - Some Basic Concepts and First Ideas
Konrad Schmuedgen
We propose and discuss how basic notions (quadratic modules, positive elements, semialgebraic sets, Archimedean orderings) and results (Positivstellensaetze) from real algebraic ge…
Hilbert space representations of cross product algebras II
Konrad Schmuedgen, Elmar Wagner
In this paper, we study and classify Hilbert space representations of cross product *-algebras of the quantized enveloping algebra with the coordinate algebras $O(E_q(2)…
Representations of cross product algebras of Podles quantum spheres
Konrad Schmuedgen, Elmar Wagner
Hilbert space representations of the cross product *-algebras of the Hopf *-algebra U_q(su_2) and its module *-algebras O(S^2_{qr}) of Podles spheres are investigated and classifie…
Dirac operator and a twisted cyclic cocycle on the standard Podles quantum sphere
Konrad Schmuedgen, Elmar Wagner
A Dirac operator D on the standard Podles sphere is defined and investigated. It yields a spectral triple such that |D|^{-z} is of trace class for Re z>0. Commutators with the Dira…
Operator representations of cross product algebras of Podles' quantum spheres
Konrad Schmuedgen, Elmar Wagner
Hilbert space representations of the cross product *-algebra of the Hopf *-algebra U_q(su_2) and its module *-algebras O(S^2_{qc}) of Podles' spheres are studied. Two classes of re…