Abstract
Twisting by a G-torsor an object endowed with an action of a group G is a classical tool. For instance one finds in the paragraph 5.3 of the book [17] the description of the “opération de torsion” in a particular context. The aim of this note is to give a formalization of this twisting operation as general as possible in the algebraic geometric framework and to present a few applications. We will focus in particular to the application to the problem of specialization of covers addressed by P. Dèbes et al. in a series of papers.
Michel Emsalem a reçu le soutien du Labex CEMPI (ANR-11-LABX-01)
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Emsalem, M. (2017). Twisting by a Torsor. In: Aryasomayajula, A., Biswas, I., Morye, A.S., Parameswaran, A.J. (eds) Analytic and Algebraic Geometry. Springer, Singapore. https://doi.org/10.1007/978-981-10-5648-2_9
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DOI: https://doi.org/10.1007/978-981-10-5648-2_9
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