Most totally real fields do not have universal forms or the Northcott property

N Nicolas Daans V Vítězslav Kala (Department of Algebra) S Siu Hang Man (Department of Algebra) M Martin Widmer (Institute of Analysis and Number Theory) P Pavlo Yatsyna (Department of Algebra)

Abstract

We show that, in the space of all totally real fields equipped with the constructible topology, the set of fields that admit a universal quadratic form, or have the Northcott property, is meager. The main tool is a theorem on the number of square classes of totally positive units represented by a quadratic lattice of a given rank.

Article Details

Volume / Issue Vol. 122, Issue 20
Published May 20, 2025
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (5)

N

Nicolas Daans

V

Vítězslav Kala

Department of Algebra

S

Siu Hang Man

Department of Algebra

M

Martin Widmer

Institute of Analysis and Number Theory

P

Pavlo Yatsyna

Department of Algebra