Ondřej ChwiedziukCharles University, Matěj DoležálekCharles University, Simona HlavinkováCharles University, Emma PěchoučkováCharles University, Zdeněk PezlarCharles University, Om PrakashCharles University, Anna RůžičkováCharles University, Mikuláš ZindulkaCharles University
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No proper generalized quadratic forms are universal over quadratic fields
We consider generalized quadratic forms over real quadratic number fields and
prove, under a natural positive-definiteness condition, that a generalized
quadratic form can only be universal if it contains a quadratic subform that is
universal. We also construct an example illustrating that the
positive-definiteness condition is necessary.