# ZERO BASED INVARIANT SUBSPACES AND FRINGE OPERATORS OVER THE BIDISK

• Received : 2015.05.16
• Published : 2016.07.01

#### Abstract

Let M be an invariant subspace of $H^2$ over the bidisk. Associated with M, we have the fringe operator $F^M_z$ on $M{\ominus}{\omega}M$. It is studied the Fredholmness of $F^M_z$ for (generalized) zero based invariant subspaces M. Also ker $F^M_z$ and ker $(F^M_z)^*$ are described.

#### Acknowledgement

Supported by : Japan Society for the Promotion of Science

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#### Cited by

1. Fredholmness of fringe operators over the bidisk vol.109, pp.3, 2017, https://doi.org/10.1007/s00013-017-1075-7