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arXiv · 1105.4662

Lambda actions of rings of integers

James Borger·Bart de Smit
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Abstract

Let O be the ring of integers of a number field K. For an O-algebra R which is torsion free as an O-module we define what we mean by a Lambda_O-ring structure on R. We can determine whether a finite etale K-algebra E with Lambda_O-ring structure has an integral model in terms of a Deligne-Ribet monoid of K. This a commutative monoid whose invertible elements form a ray class group.

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James Borger, Bart de Smit. 2011-05-24. Lambda actions of rings of integers. https://arxiv.org/abs/1105.4662

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