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تسجيل مستخدم جديدFailure of the local-global principle for isotropy of quadratic forms over rational function fields
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We prove the failure of the local-global principle, with respect to all discrete valuations, for isotropy of quadratic forms over a rational function field of transcendence degree at least 2 over the complex numbers. Our construction involves the generalized Kummer varieties considered by Borcea and Cynk--Hulek.
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