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Related papers: Witt equivalence of function fields of conics

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Two fields are Witt equivalent if their Witt rings of symmetric bilinear forms are isomorphic. Witt equivalent fields can be understood to be fields having the same quadratic form theory. The behavior of finite fields, local fields, global…

Rings and Algebras · Mathematics 2016-04-26 Paweł Gładki , Murray Marshall

This paper introduces a novel approach to the axiomatic theory of quadratic forms. We work internally in a category of certain partially ordered sets, subject to additional conditions which amount to a strong form of local presentability.…

Rings and Algebras · Mathematics 2018-03-30 Pawel Gladki , Krzysztof Worytkiewicz

We recall some basic computations in the Milnor-Witt K-theory of a field, following Morel. We then focus on the Witt K-theory of a field of characteristic two and give an elementary proof of the fact that it is isomorphic as a graded ring…

Algebraic Geometry · Mathematics 2023-06-30 Robin Carlier

In our work we investigate Witt equivalence of general function fields over global fields. It is proven that for any two such fields K and L the Witt equivalence induces a canonical bijection between Abhyankar valuations on K and L having…

Rings and Algebras · Mathematics 2016-02-01 Pawel Gladki , Murray Marshall

This paper presents fundamental algorithms for the computational theory of quadratic forms over number fields. In the first part of the paper, we present algorithms for checking if a given non-degenerate quadratic form over a fixed number…

Number Theory · Mathematics 2016-02-04 Przemysław Koprowski , Alfred Czogała

Let F be a field of characteristic two. We determine all non-hyperbolic quadratic forms over F that are Witt equivalent to a second trace form.

Number Theory · Mathematics 2007-05-23 A. C. de la Maza

Counterparts of several classical results of number theory are proven for the ring of polynomials with coefficients in a number field. A theorem of Milnor that determines the Witt ring of a function field is applied to prove an analogue of…

Number Theory · Mathematics 2024-07-09 William Duke

The Witt group of skew hermitian forms over a division algebra $D$ with symplectic involution is shown to be canonically isomorphic to the Witt group of symmetric bilinear forms over the Severi-Brauer variety of $D$ with values in a…

K-Theory and Homology · Mathematics 2026-05-27 Anne Quéguiner-Mathieu , Jean-Pierre Tignol

We provide, explicitly, equivalences and dual equivalences between categories of abstract quadratic forms theories and subcategories of multifields and multirings, that will bring new perspectives and methods to the abstract theories of…

Commutative Algebra · Mathematics 2020-08-31 Hugo Rafael de Oliveira Ribeiro , Kaique Matias de Andrade Roberto , Hugo Luiz Mariano

The Witt ring of symmetric bilinear forms over a field has divided power operations. On the other hand, it follows from Garibaldi-Merkurjev-Serre's work on cohomological invariants that all operations on the Witt ring are essentially linear…

K-Theory and Homology · Mathematics 2023-09-11 Burt Totaro

Over a field of characteristic 2, we give a complete classification of quadratic and bilinear forms of dimension 5 that are minimal over the function field of an arbitrary conic. This completes the unique known case due to Faivre concerning…

Commutative Algebra · Mathematics 2025-04-10 Adam Chapman , Ahmed Laghribi

We extend to characteristic two recent results about isotropy of quadratic forms over function fields. In particular, we provide a characterization of function fields not only of quadratic forms but also more generally of polynomials in…

Number Theory · Mathematics 2024-08-07 Kristýna Zemková

In a previous paper Cuntz and Deninger introduced the ring $C(R)$ for a perfect $\mathbb{F}_p$-algebra $R$. The ring $C(R)$ is canonically isomorphic to the $p$-typical Witt ring $W(R)$. In fact there exist canonical isomorphisms $\alpha_n…

Number Theory · Mathematics 2016-06-06 Sina Ghassemi-Tabar

The analogy between the arithmetic of varieties over number fields and the arithmetic of varieties over function fields is a leading theme in arithmetic geometry. This analogy is very powerful but there are some gaps. In this note we will…

Algebraic Geometry · Mathematics 2016-06-22 Carlo Gasbarri

We study some properties of quadratic forms with values in a field whose underlying vector spaces are endowed with the structure of right vector spaces over a division ring extension of that field. Some generalized notions of isotropy,…

Rings and Algebras · Mathematics 2019-06-18 Amir Hossein Nokhodkar

The difference between slice and doubly-slice knots is reflected in algebra by the difference between metabolic and hyperbolic Blanchfield linking forms. We exploit this algebraic distinction to refine the classical Witt group of linking…

Geometric Topology · Mathematics 2015-08-04 Patrick Orson

For a discrete valuation ring $R$ with quotient field $K$ and residue field $F$ both of characteristic not 2, we study low-dimensional quadratic forms with Witt class in the $n$-th power of the fundamental ideal of $F$ resp. $K$ and point…

Number Theory · Mathematics 2024-04-23 Nico Lorenz

Many classical results concerning quadratic forms have been extended to forms over algebras with involution. However, not much is known in the case of forms without any symmetry property. The present paper will establish Witt cancellation…

Representation Theory · Mathematics 2013-05-24 Eva Bayer-Fluckiger , Daniel Moldovan

We prove that two arithmetically significant extensions of a field F coincide if and only if the Witt ring WF is a group ring Z/n[G]. Furthermore, working modulo squares with Galois groups which are 2-groups, we establish a theorem…

Algebraic Topology · Mathematics 2007-05-23 Alejandro Adem , Wenfeng Gao , Dikran Karagueuzian , Jan Minac

We prove that there exists, up to isomorphism, exactly one function field over the finite field of two elements of class number one and genus four. This result, together with the ones of MacRae, Madan, Leitzel, Queen and Stirpe, establishes…

Number Theory · Mathematics 2014-12-17 Martha Rzedowski-Calderón , Gabriel Villa-Salvador
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