An isomorphism between the narrow ideal class group of squared ideals of a quadratic number field and the kernel of a homomorphism between cohomology groups for Pell conics

Samuel A. Hambleton

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arXiv · 1108.1610

An isomorphism between the narrow ideal class group of squared ideals of a quadratic number field and the kernel of a homomorphism between cohomology groups for Pell conics

Samuel A. Hambleton

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Abstract

Two proofs are provided that the narrow ideal class group of squared ideals of a quadratic number field is isomorphic to the kernel of a homomorphism between cohomology groups for Pell conics, Lemmermeyer's obstruction to descent for Pell conics. These proofs make use of a particular subgroup of a Pell conic over algebraic numbers.

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Samuel A. Hambleton. 2011-08-08. An isomorphism between the narrow ideal class group of squared ideals of a quadratic number field and the kernel of a homomorphism between cohomology groups for Pell conics. https://arxiv.org/abs/1108.1610

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