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On the computation of spectra in free probability

Franz Lehner
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Abstract

We use free probability techniques to compute borders of spectra of non hermitian operators in finite von Neumann algebras which arise as `free sums' of `simple' operators. To this end, the resolvent is analyzed with the aid of the Haagerup inequality. Concrete examples coming from reduced C*-algebras of free product groups and leading to systems of polynomial equations illustrate the approach.

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Franz Lehner. 2000-08-11. On the computation of spectra in free probability. https://doi.org/10.1006/jfan.2001.3748

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