# An algebraic approach to the radius of comparison

@article{Blackadar2010AnAA, title={An algebraic approach to the radius of comparison}, author={Bruce E. Blackadar and Leonel Robert and Aaron Tikuisis and Andrew S. Toms and Wilhelm Winter}, journal={Transactions of the American Mathematical Society}, year={2010}, volume={364}, pages={3657-3674} }

The radius of comparison is an invariant for unital C∗-algebras which extends the theory of covering dimension to noncommutative spaces. We extend its definition to general C∗-algebras, and give an algebraic (as opposed to functional-theoretic) reformulation. This yields new permanence properties for the radius of comparison which strengthen its analogy with covering dimension for commutative spaces. We then give several applications of these results. New examples of C∗-algebras with finite…

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