Abstract
In this paper we study the \(\kappa \)-word problem for the pseudovariety \(\mathbf{LG}\) of local groups, where \(\kappa \) is the canonical signature consisting of the multiplication and the pseudoinversion. We solve this problem by transforming each arbitrary \(\kappa \)-term \(\alpha \) into another one \(\alpha ^*\) called the \(\mathbf{LG}\)-canonical form of \(\alpha \) and by showing that different canonical forms have different interpretations over \(\mathbf{LG}\). The procedure of construction of these canonical forms consists in applying reductions determined by a set \(\Sigma \) of \(\kappa \)-identities. As a consequence, \(\Sigma \) is a basis of \(\kappa \)-identities for the \(\kappa \)-variety generated by \(\mathbf{LG}\).
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Acknowledgements
This work was supported by the European Regional Development Fund, through the programme COMPETE, and by the Portuguese Government through FCT (Fundação para a Ciência e a Tecnologia) within the Projects UIDB/00013/2020, UIDP/00013/2020 and PEst-C/MAT/UI0013/2014.
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Communicated by Jorge Almeida.
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Costa, J.C., Nogueira, C. & Teixeira, M.L. The word problem for \(\kappa \)-terms over the pseudovariety of local groups. Semigroup Forum 103, 439–468 (2021). https://doi.org/10.1007/s00233-021-10207-9
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DOI: https://doi.org/10.1007/s00233-021-10207-9