Abstract
In this paper we give a complete characterization of the nth roots of a coquaternion \(\mathsf {q}\). In particular, we show that the number and type of roots—isolated and/or hyperboloidal—depend on the nature of \(\mathsf {q}\), on the parity of n and (eventually) on the sign of the real part of \(\mathsf {q}\). We also show how the coquaternionic formalism can be used to obtain, in a simple manner, explicit expressions for the real nth roots of any \(2\times 2\) real matrix.
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22 November 2018
Unfortunately, the reference Pogoruy [1] has been published with the incorrect Journal’s name.
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Communicated by Rafał Abłamowicz.
Research at CMAT was financed by Portuguese Funds through FCT - Fundação para a Ciência e a Tecnologia, within the Project UID/MAT/00013/2013. Research at NIPE was carried out within the funding with COMPETE reference number POCI-01-0145-FEDER-006683 (UID/ECO/03182/2013), with the FCT/MEC’s (Fundação para a Ciência e a Tecnologia, I.P.) financial support through national funding and by the ERDF through the Operational Programme on “Competitiveness and Internationalization-COMPETE 2020” under the PT2020 Partnership Agreement.
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Falcão, M.I., Miranda, F., Severino, R. et al. On the Roots of Coquaternions. Adv. Appl. Clifford Algebras 28, 97 (2018). https://doi.org/10.1007/s00006-018-0914-3
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DOI: https://doi.org/10.1007/s00006-018-0914-3
Keywords
- Coquaternions
- Roots
- Polar form
- Similarity class and quasi-similarity class of a coquaternion
- Matrix equations