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Products of Idempotent Operators

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Abstract

The goal of this article is to study the set of all products EF with E, F idempotent operators defined on a Hilbert space. We present characterizations of this set in terms of operator ranges, Hilbert space decompositions and generalized inverses.

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Authors and Affiliations

  1. Instituto Argentino de Matemática “Alberto P. Calderón”, CONICET, Saavedra 15 Piso 3, 1083, Buenos Aires, Argentina

    M. Laura Arias, Gustavo Corach & Alejandra Maestripieri

  2. Dpto. de Matemática, Facultad de Ingeniería, Universidad de Buenos Aires, Av. Paseo Colon 850, 1063, Buenos Aires, Argentina

    M. Laura Arias, Gustavo Corach & Alejandra Maestripieri

Authors
  1. M. Laura Arias
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  2. Gustavo Corach
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  3. Alejandra Maestripieri
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Corresponding author

Correspondence to M. Laura Arias.

Additional information

M. L. Arias and G. Corach are partially supported by CONICET (PIP 11220120100426), UBACYT 20020130100637 and FONCYT (PICT 2014-1776). A. Maestripieri is supported by CONICET (PIP 168-2014-2016).

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Arias, M.L., Corach, G. & Maestripieri, A. Products of Idempotent Operators. Integr. Equ. Oper. Theory 88, 269–286 (2017). https://doi.org/10.1007/s00020-017-2363-0

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  • DOI: https://doi.org/10.1007/s00020-017-2363-0

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