Springer’s Odd Degree Extension Theorem for quadratic forms over semilocal rings
نویسندگان
چکیده
A fundamental result of Springer says that a quadratic form over field characteristic ≠2 is isotropic if it so after an odd degree extension. In this paper we generalize Springer’s theorem as follows. Let R be arbitrary semilocal ring, let S finite R-algebra constant degree, which étale or generated by one element, and q nonsingular R-quadratic whose base ring extension qS isotropic. We show then already
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ژورنال
عنوان ژورنال: Indagationes Mathematicae
سال: 2021
ISSN: ['0019-3577', '1872-6100']
DOI: https://doi.org/10.1016/j.indag.2021.06.009