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A Note on Quadratic Forms and the u-invariant

Published online by Cambridge University Press:  20 November 2018

Roger Ware
Roger Ware*
Affiliation:
University of Kansas, Lawrence, Kansas; The Pennsylvania State University, University Park, Pennsylvania
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The u-invariant of a field F, u = u(F), is defined to be the maximum of the dimensions of anisotropic quadratic forms over F. If F is a non-formally real field with a finite number q of square classes then it is known that u ≦ q. The purpose of this note is to give some necessary and sufficient conditions for equality in terms of the structure of the Witt ring of F.

Type
Research Article
Information
Canadian Journal of Mathematics , Volume 26 , Issue 5 , October 1974 , pp. 1242 - 1244
Copyright
Copyright © Canadian Mathematical Society 1974

References

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