L^2 rho form for normal coverings of fibre bundles

Sara Azzali

doi:10.1142/s0129167x11007161

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arXiv · 0704.0909

L^2 rho form for normal coverings of fibre bundles

Sara Azzali

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Abstract

We define the secondary invariants L^2- eta and -rho forms for families of generalized Dirac operators on normal coverings of fibre bundles. On the covering family we assume transversally smooth spectral projections, and Novikov--Shubin invariants bigger than 3(dim B+1) to treat the large time asymptotic for general operators. In the particular case of a bundle of spin manifolds, we study the L^2- rho class in relation to the space of positive scalar curvature vertical metrics.

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Sara Azzali. 2010-09-05. L^2 rho form for normal coverings of fibre bundles. https://doi.org/10.1142/s0129167x11007161

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