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Induced Quaternion Algebras in the Schur Group

Published online by Cambridge University Press:  20 November 2018

Richard A. Mollin*
Affiliation:
Queen's University, Kingston, Ontario
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Let K be a finite, imaginary and abelian extension of the rational number field Q, and let M be the maximal real subfield of K. It is well known that each element of order 2 in S(K), the Schur group of K, is induced from an element of order 2 in B(M), the Brauer group of M; i.e., if D is a quaternion division algebra central over K such that its class [D] in B(K) is in fact in S(K) then [D] = [B ⊗MK] where B is a quaternion division algebra with [B] ∈ B(M). A natural question to ask is: “When is every element of S(K) of order 2 induced from S(M)?” The main result of this paper is to provide necessary and sufficient conditions for this to occur when G(L/K), the Galois group of L over K, is cyclic where L is the smallest root of unity field containing K.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1981

References

1. Janusz, G. J., The Schur group of an algebraic number field, Annals of Math. 103 (1976), 253281.Google Scholar
2. Mollin, R., Algebras with uniformly distributed invariants, J. Algebra 44 (1977), 271282.Google Scholar
3. Mollin, R., The Schur group of afield of characteristic zero, Pacific J. Math. 76 (1978), 471478.Google Scholar
4. Mollin, R., Uniform distribution classified, Math. Z. 165 (1979), 199211.Google Scholar
5. Mollin, R., Induced p-elements in the Schur group, Pacific J. Math. 90 (1980), 169176.Google Scholar
6. Mollin, R., Splitting fields and group characters, J. Reine Angew. Math. 315 (1980), 107114.Google Scholar
7. Pendergrass, J. W., The 2-part of the Schur group, J. Algebra 41 (1976), 422438.Google Scholar
8. Pendergrass, J. W., The Schur subgroup of the Brauer group, (preprint).Google Scholar
9. Pendergrass, J. W., Calculations in the Schur group, J. Algebra 41 (1976), 422438.Google Scholar
10. Yamada, T., The Schur subgroup of the Brauer group, Lecture Notes in Mathematics 397 (Springer-Verlag, 1974).Google Scholar