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arXiv · 0903.2708

Algebras of Fractions and Strict Positivstellensätze for *-Algebras

Konrad Schmuedgen
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Abstract

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 prove abstract noncommutative strict Positivstellensätze for $\cA$. Multi-grading of $\cA$ are studied as technical tools to verify the assumptions of this theorem. As applications we obtain new strict Positivstellensätze for the Weyl algebra and for the Lie algebra $\cg$ of the affine group of the real line. We characterize integrable representations of the Lie algebra $\cg$ in terms of resolvents of the generators and derive a new integrability criterion for representations of $\cg$.

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BibTeXRIS

Konrad Schmuedgen. 2009-03-16. Algebras of Fractions and Strict Positivstellensätze for *-Algebras. https://arxiv.org/abs/0903.2708

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