Abstract
In this paper we obtain a criterion under which the bijectivity of the canonical morphism of a weak Galois extension associated to a weak invertible entwining structure is equivalent to the existence of a strong connection form. Also we obtain an explicit formula for a strong connection under equivariant projective conditions or under coseparability conditions.
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Supported by Ministerio de Educación, Xunta de Galicia and by FEDER (Grant Nos. MTM2010-15634, MTM2009-14464-C02-01, PGIDT07PXB322079PR)
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Alonso Álvarez, J.N., Fernández Vilaboa, J.M. & González Rodríguez, R. Strong connections and invertible weak entwining structures. Acta. Math. Sin.-English Ser. 28, 1443–1460 (2012). https://doi.org/10.1007/s10114-012-0088-1
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DOI: https://doi.org/10.1007/s10114-012-0088-1