English
Related papers

Related papers: The Poincar\'e-Hopf Theorem for line fields revisi…

200 papers

The Hopf index, a topological invariant that quantifies the linking of preimage fibers, is fundamental to the structure and stability of hopfions. In this work, we propose a new mathematical framework for modeling hopfions with high Hopf…

Soft Condensed Matter · Physics 2026-04-21 Yuta Nozaki , Darian Hall , Ivan I. Smalyukh , Yuya Koda

We examine the validity of the Poincar\'e inequality for degenerate, second-order, elliptic operators $H$ in divergence form on $L_2(\Ri^{n}\times\Ri^{m})$. We assume the coefficients are real symmetric and $a_1H_\delta\geq H\geq…

Analysis of PDEs · Mathematics 2014-12-09 Derek W. Robinson , Adam Sikora

We present a general fixed point theorem which can be seen as the quintessence of the principles of proof for Banach's Fixed Point Theorem, ultrametric and certain topological fixed point theorems. It works in a minimal setting, not…

Commutative Algebra · Mathematics 2013-04-02 Katarzyna Kuhlmann , Franz-Viktor Kuhlmann

Over these past few years several quantum-gravity research groups have been exploring the possibility that in some Planck-scale nonclassical descriptions of spacetime one or another form of nonclassical spacetime symmetries might arise. One…

High Energy Physics - Theory · Physics 2008-11-26 Alessandra Agostini , Giovanni Amelino-Camelia , Michele Arzano , Antonino Marcianó , Ruggero Altair Tacchi

We deform Heisenberg algebra and corresponding coalgebra by twist. We present undeformed and deformed tensor identities. Coalgebras for the generalized Poincar\'{e} algebras have been constructed. The exact universal $R$-matrix for the…

Mathematical Physics · Physics 2015-06-04 Stjepan Meljanac , Andjelo Samsarov , Rina Strajn

The paper establishes a version of the Hopf boundary point lemma for sections of a vector bundle over a manifold with boundary. This result may be viewed as a counterpart to the tensor maximum principle obtained by R. Hamilton in 1986.…

Differential Geometry · Mathematics 2008-04-03 Artem Pulemotov

We present a comprehensive $L^2$-theory for the $\overline\partial$-operator on singular complex curves, including $L^2$-versions of the Riemann-Roch theorem and some applications.

Complex Variables · Mathematics 2015-06-02 Jean Ruppenthal , Martin Sera

In this paper I would like to show how the Deformed Special Relativity family of models - developed to approach spacetime quantization - can actually be applied to the description of classical cosmology. I use the bicrossproduct basis of…

General Relativity and Quantum Cosmology · Physics 2025-03-14 Niccoló Loret

Let $F$ be a finite field with characteristic greater than two. Define a \emph{Besicovitch set} in $F^4$ to be a set $P \subseteq F^4$ containing a line in every direction. The \emph{Kakeya conjecture} asserts that $|P| \approx |F|^4$. A…

Classical Analysis and ODEs · Mathematics 2007-05-23 Terence Tao

In this paper we study extension theorems associated with general varieties in two dimensional vector spaces over finite fields. Applying Bezout's theorem, we obtain the sufficient and necessary conditions on general curves where sharp…

Classical Analysis and ODEs · Mathematics 2010-12-01 Doowon Koh , Chun-Yen Shen

In arXiv:1709.07504 Ardila and Aguiar give a Hopf monoid structure on hypergraphs as well as a general construction of polynomial invariants on Hopf monoids. Using these results, we define in this paper a new polynomial invariant on…

Combinatorics · Mathematics 2021-07-09 Jean-Christophe Aval , Théo Karaboghossian , Adrian Tanasa

The Poincar\'{e} lemma (or Volterra theorem) is of utmost importance both in theory and in practice. It tells us every differential form which is closed, is locally exact. In other words, on a contractible manifold all closed forms are…

General Mathematics · Mathematics 2019-06-03 A. Lesfari

For an arbitrary infinite field k of characteristic p > 0, we describe the structure of a block of the algebraic monoid M_n(k) (all n x n matrices over k), or, equivalently, a block of the Schur algebra S(n,p), whose simple modules are…

Representation Theory · Mathematics 2008-03-11 Stephen Doty , Stuart Martin

The notion of the supercharacter theory was introduced by P.Diaconis and I.M.Isaaks in 2008. In this paper we review the main statements of the general theory, we observe the construction of supercharacter theory for algebra groups and the…

Representation Theory · Mathematics 2016-11-29 A. N. Panov

In this paper we consider an abstract class of quasi-linear para-differential equations on the circle. For each equation in the class we prove the existence of a change of coordinates which conjugates the equation to a diagonal and constant…

Analysis of PDEs · Mathematics 2020-03-17 Roberto Feola , Felice Iandoli

A classical theorem of H. Hopf asserts that a closed connected smooth manifold admits a nowhere vanishing vector field if and only if its Euler characteristic is zero. R. Brown generalized Hopf's result to topological manifolds, replacing…

Algebraic Topology · Mathematics 2011-05-11 Lucilia Borsari , Fernanda Cardona , Peter Wong

In this paper we investigate the relation between complexified Fenchel-Nielsen coordinates and spectral network coordinates on Seiberg-Witten moduli space. The main technique is the comparison of exact expressions for the expectation value…

High Energy Physics - Theory · Physics 2019-10-02 T. Daniel Brennan , Gregory W. Moore

We show that every closed L_infty,loc - form on R^n is exact. Differential is understood in the sense of currents. The proof does not use any explicit geometric constructions. De Rham theorem follows.

Differential Geometry · Mathematics 2007-12-12 Vladimir Gol'dshtein , Stanislav Dubrovskiy

We investigate the problem of Poincar\'e duality for $L^p$ differential forms on bounded subanalytic submanifolds of $\mathbb{R}^n$ (not necessarily compact). We show that, when $p$ is sufficiently close to $1$ then the $L^p$ cohomology of…

Algebraic Geometry · Mathematics 2020-01-16 Guillaume Valette

For any smooth Hurwitz curve $\mathcal{H}_n: \, XY^n+YZ^n+X^nZ=0$ over the finite field $\mathbb{F}_{p}$, an explict description of its Weierstrass points for the morphism of lines is presented. As a consequence, the full automorphism group…

Algebraic Geometry · Mathematics 2018-11-26 Nazar Arakelian , Herivelto Borges , Pietro Speziali