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arXiv · 1310.8564

Estimates for spectral density functions of matrices over C[Z^d]

Wolfgang Lueck
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Abstract

We give a polynomial bound on the spectral density function of a matrix over the complex group ring of Z^d. It yields an explicit lower bound on the Novikov-Shubin invariant associated to this matrix showing in particular that the Novikov-Shubin invariant is larger than zero.

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Wolfgang Lueck. 2014-10-29. Estimates for spectral density functions of matrices over C[Z^d]. https://arxiv.org/abs/1310.8564

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