## Extensions of the index in factors of type $\textrm {II}_{\infty }$

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- by Michael Gartenberg PDF
- Proc. Amer. Math. Soc.
**43**(1974), 163-168 Request permission

## Abstract:

In this paper we show that the analytic index has no continuous extension to those operators in a factor of type ${\Pi _\infty }$ on a separable Hilbert space which are not semi-Fredholm in the Breuer sense. A similar result has already been proved by Coburn and Lebow [**3**] for factors of type ${I_\infty }$. Here we use Breuer’s generalized Fredholm theory to extend their result to the more general setting.

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**22**#1824.

## Additional Information

- © Copyright 1974 American Mathematical Society
- Journal: Proc. Amer. Math. Soc.
**43**(1974), 163-168 - MSC: Primary 46L10
- DOI: https://doi.org/10.1090/S0002-9939-1974-0328614-2
- MathSciNet review: 0328614