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Densities of 4-ranks of $K_2(\mathcal{O})$

Robert Osburn
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Abstract

Conner and Hurrelbrink established a method of determining the structure of the 2-Sylow subgroup of the tame kernel $K_2(\mathcal{O})$ for certain quadratic number fields. Specifically, the 4-rank for these fields was characterized in terms of positive definite binary quadratic forms. Numerical calculations led to questions concerning possible density results of the 4-rank of tame kernels. In this paper, we succeed in giving affirmative answers to these questions.

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Robert Osburn. 2007-03-12. Densities of 4-ranks of $K_2(\mathcal{O})$. https://doi.org/10.4064/aa102-1-4

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