Fredholm properties of a linear relation through invariant subspaces

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Published: Oct 23, 2026
DOI: https://doi.org/10.5556/j.tkjm.58.2027.6021
Keywords:
Linear relation, Invariant subspace, Fredholm properties

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Maher Mnif
University of Sfax
Nihel Feki

Abstract

In this paper, we present a sufficient conditions under which a linear relation (multivalued linear operator) admits an invariant subspace on a Banach space $X$. Also, we give some Fredholm properties of the linear relation $T$ using properties of its restriction to an invariant subspace $M$ and the linear relation induced by $T$ over the quotient subspace $X/M$.

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How to Cite
Mnif, M., & Feki, N. (2026). Fredholm properties of a linear relation through invariant subspaces. Tamkang Journal of Mathematics, 58(1). https://doi.org/10.5556/j.tkjm.58.2027.6021
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Online First
Section
Papers
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