The Euler characteristic is stable under compact perturbations

Ambrozie, Calin-Grigore

doi:10.1090/S0002-9939-96-03283-2

The Euler characteristic is stable under compact perturbations
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Proc. Amer. Math. Soc. 124 (1996), 2041-2050 Request permission

Abstract:

We prove in the general case the stability under compact perturbations of the index (i.e. the Euler characteristic) of a Fredholm complex of Banach spaces. In particular, we obtain the corresponding stability property for Fredholm multioperators. These results are the consequence of a similar statement, concerning more general objects called Fredholm pairs.

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