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Roberts orthogonality for \({2 \times 2}\) complex matrices

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Abstract

We give a complete description of matrices A and B from \({\mathbb{M}_{2}(\mathbb{C})}\) which are Roberts orthogonal to each other. Necessary and sufficient conditions for Roberts orthogonality of A and B are also given in terms of traces of matrices.

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Acknowledgement

We thank the referee for useful comments and suggestions.

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Authors and Affiliations

  1. Department of Mathematics, Faculty of Science, University of Zagreb, Bijenička cesta 30, 10000, Zagreb, Croatia

    LJ. Arambašić

  2. Faculty of Mining, Geology and Petroleum Engineering, University of Zagreb, Pierottijeva 6, 10000, Zagreb, Croatia

    R. Rajić

Authors
  1. LJ. Arambašić
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  2. R. Rajić
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Correspondence to R. Rajić.

Additional information

This work has been fully supported by the Croatian Science Foundation under the project IP-2016-06-1046.

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Arambašić, L., Rajić, R. Roberts orthogonality for \({2 \times 2}\) complex matrices. Acta Math. Hungar. 157, 220–228 (2019). https://doi.org/10.1007/s10474-018-0870-3

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  • DOI: https://doi.org/10.1007/s10474-018-0870-3

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