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arXiv · 1909.04007

A Family of Almost Invertible Infinite Matrices

Daniel P. Bossaller
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Abstract

An algebraic analogue of the family of Fredholm operators is introduced for the family of row and column finite matrices, dubbed "Fredholm matrices." In addition, a measure is introduced which indicates how far a Fredholm matrix is from an invertible matrix. It is further shown that this measure respects multiplication, is invariant under perturbation by a matrix from $M_\infty(K)$, and is invariant under conjugation by an invertible row and column finite matrix.

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Daniel P. Bossaller. 2019-09-09. A Family of Almost Invertible Infinite Matrices. https://arxiv.org/abs/1909.04007

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