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New expansionary and rotational quadratic forms are constructed for $E^n$-endomorphisms. Relations amongst the various eigenvalues, eigendirections and matrix invariants are established, including propositions on complexity and geometric…

Rings and Algebras · Mathematics 2023-07-17 Geoff Prince

Let F be a totally real number field of odd degree. We prove several purely local criteria for the asymptotic Fermat's Last Theorem to hold over F, and also for the non-existence of solutions to the unit equation over F. For example, if 2…

Number Theory · Mathematics 2022-05-11 Nuno Freitas , Alain Kraus , Samir Siksek

There are many four vertex type theorems appearing in the literature, coming in both smooth and discrete flavors. The most familiar of these is the classical theorem in differential geometry, which states that the curvature function of a…

Metric Geometry · Mathematics 2023-02-09 Wiktor Mogilski , Kyle Grant

Main Theorem (3.3): Let $M$ be a compact four-dimensional manifold either with curvature, positive on complex isotropic two-planes, or self-dual of positive scalar curvature. If $\pi_1 (M)$ admits a nontrivial unitary representation, and…

dg-ga · Mathematics 2016-08-31 Alexander G. Reznikov

We compute the genus of a rational quadratic form in terms of the K-theory of a C*-algebra attached to the adelic orthogonal group of the form. As a corollary, one gets a higher composition law for the rational quadratic forms. As an…

Number Theory · Mathematics 2019-10-09 Igor Nikolaev

Four-dimensional gravity admits many equivalent formulations - metric, Einstein-Cartan, teleparallel, McDowell-Mansouri, among others - each offering distinct advantages, particularly, in view of quantization. We propose a new formulation…

General Relativity and Quantum Cosmology · Physics 2026-03-13 Maïté Dupuis , Florian Girelli , Oleksandra Hrytseniak , Wolfgang Wieland

Let $p$ and $q$ be anisotropic quadratic forms of dimension $\geq 2$ over a field $F$. In a recent article, we formulated a conjecture describing the general constraints which the dimensions of $p$ and $q$ impose on the isotropy index of…

Commutative Algebra · Mathematics 2017-10-27 Stephen Scully

We study universal quadratic forms over totally real number fields using Dedekind zeta functions. In particular, we prove an explicit upper bound for the rank of universal quadratic forms over a given number field $K$, under the assumption…

Number Theory · Mathematics 2025-10-27 Vítězslav Kala , Mentzelos Melistas

This work is a continuation of studies presented in the papers arXiv:0911.5597, arXiv:1003.4523. In the work it is demonstrated that with the use of one and the same parameter deformation may be described for several cases of the General…

General Relativity and Quantum Cosmology · Physics 2010-06-28 A. E. Shalyt-Margolin

We develop a sequential-topological study of rational points of schemes of finite type over local rings typical in higher dimensional number theory and algebraic geometry. These rings are certain types of multidimensional complete fields…

Algebraic Geometry · Mathematics 2012-03-02 Alberto Camara

This paper proposes new quadratic constraints (QCs) to bound a quadratic polynomial. Such QCs can be used in dissipation ineqaulities to analyze the stability and performance of nonlinear systems with quadratic vector fields. The proposed…

Dynamical Systems · Mathematics 2022-09-09 Shih-Chi Liao , Maziar S. Hemati , Peter Seiler

For every algebraically closed field $\boldsymbol k$ of characteristic different from $2$, we prove the following: (1) Generic finite dimensional (not necessarily associative) $\boldsymbol k$-algebras of a fixed dimension, considered up to…

Algebraic Geometry · Mathematics 2015-01-20 Vladimir L. Popov

For $\mathrm{O}(\mathrm{q},k)$, the orthogonal group over a field $k$ of characteristic 2 with respect to a quadratic form $\mathrm{q}$, we discuss the isomorphism classes of fixed points of involutions. When the quadratic space is either…

Group Theory · Mathematics 2023-01-18 Mark Hunnell , John Hutchens

A (positive definite and integral) quadratic form is said to be $\textit{prime-universal}$ if it represents all primes. Recently, Doyle and Williams in [2] classified all prime-universal diagonal ternary quadratic forms, and all…

Number Theory · Mathematics 2020-06-29 Jangwon Ju , Daejun Kim , Kyoungmin Kim , Mingyu Kim , Byeong-Kweon Oh

The survey is devoted to the rationality question of finite linear groups. We concentrate on lower-dimensional cases, especially on the case of dimension four.

Algebraic Geometry · Mathematics 2010-04-26 Yuri G. Prokhorov

It is well known that every non-degenerate quadratic form admits a decomposition into an orthogonal sum of its anisotropic part and a hyperbolic form. This decomposition is unique up to isometry. In this paper we present an algorithm for…

Number Theory · Mathematics 2021-09-10 Przemysław Koprowski , Beata Rothkegel

We prove an explicit upper bound on the number of real quadratic fields that admit a universal quadratic form of a given rank, thus establishing a density zero statement. More generally, we obtain such a result for totally positive definite…

Number Theory · Mathematics 2025-05-23 Vitezslav Kala , Pavlo Yatsyna , Błażej Żmija

Let R be a regular semi-local domain containing a field such that all the residue fields are infinite. Let K be the fraction field of R. Let q be a quadratic space over R on a free rank n R-module P such that the projective quadric q=0 is…

Algebraic Geometry · Mathematics 2013-02-21 Ivan Panin , Konstantin Pimenov

We study rationality constructions for smooth complete intersections of two quadrics over nonclosed fields. Over the real numbers, we establish a criterion for rationality in dimension four.

Algebraic Geometry · Mathematics 2021-01-25 Brendan Hassett , János Kollár , Yuri Tschinkel

Suppose that $F$ is a smooth and connected complex surface (not necessarily compact) containing a smooth rational curve with positive self-intersection. We prove that if there exists a non-constant meromorphic function on $F$, then the…

Complex Variables · Mathematics 2025-01-29 Serge Lvovski