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Related papers: Computing the Hopf invariant

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We give two formulas for the generalized Hopf invariant and 4-fold Toda brackets which are useful in computations of homotopy groups of spheres.

Algebraic Topology · Mathematics 2022-01-03 Hideaki Oshima , Katsumi Oshima

In this paper we will compute the effect of the James-Hopf map after applying the Bousfield-Kuhn functor on Morava E-theory, and then compute the monochromatic Hopf invariant of the $\beta$ family using this cohomological information.

Algebraic Topology · Mathematics 2014-10-28 Guozhen Wang

This paper gives a summary of our approach to invariants of three manifolds via right integrals on finite dimensional Hopf algebras and their relation to the Kirby calculus.

Geometric Topology · Mathematics 2007-05-23 Louis H. Kauffman

To gain deeper insight into the complex, stable, and robust configurations of magnetic textures, topological characterisation has proven essential. In particular, while the skyrmion number is a well-established topological invariant for 2D…

Mesoscale and Nanoscale Physics · Physics 2025-04-07 Ross Knapman , Maria Azhar , Alessandro Pignedoli , Louis Gallard , Riccardo Hertel , Jonathan Leliaert , Karin Everschor-Sitte

In this paper we define the bi-orthogonal sectional curvature and we present two modified Yamabe invariants for compact 4-dimensional manifolds. In particular we obtained a relationship between one of these invariants and a Hopf conjecture.

Differential Geometry · Mathematics 2012-08-01 Ezio Araujo Costa

We give a formula for the cohomological invariants of a root stack, which we apply to compute the cohomological invariants and the Brauer group of the stack of admissible double coverings.

Algebraic Geometry · Mathematics 2020-10-22 Andrea Di Lorenzo , Roberto Pirisi

We study Hopf algebras via tools from geometric invariant theory. We show that all the invariants we get can be constructed using the integrals of the Hopf algebra and its dual together with the multiplication and the comultiplication, and…

Quantum Algebra · Mathematics 2016-02-26 Ehud Meir

We study pure ordered simplicial complexes (i.e., simplicial complexes with a linear order on their ground sets) from the Hopf-theoretic point of view. We define a \textit{Hopf class} to be a family of pure ordered simplicial complexes that…

Combinatorics · Mathematics 2024-09-04 Federico Castillo , Jeremy L. Martin , Jose A. Samper

We present a new approach to equivariant version of the topological complexity, called a symmetric topological complexity. It seems that the presented approach is more adequate for the analysis of an impact of symmetry on the the motion…

Algebraic Topology · Mathematics 2015-06-12 Wojciech Lubawski , Wacław Marzantowicz

We give an overview of the existing algorithms to compute nonunique factorization invariants in finitely generated monoids.

Commutative Algebra · Mathematics 2015-04-29 P. A. García-Sánchez

An algorithmic computation of the set of unpointed stable homotopy classes of equivariant fibrewise maps was described in a recent paper of the author and his collaborators. In the present paper, we describe a simplification of this…

Algebraic Topology · Mathematics 2013-12-10 Lukáš Vokřínek

This is a survey of known algorithms in algebraic topology with a focus on finite simplicial complexes and, in particular, simplicial manifolds. Wherever possible an elementary approach is chosen. This way the text may also serve as a…

Algebraic Topology · Mathematics 2007-05-23 Michael Joswig

In light of $\phi$-mapping topological current theory, the inner topological structure of Hopf invariant is investigated. It is revealed that Hopf invariant is just the winding number of Gauss mapping. According to the inner structure of…

Mathematical Physics · Physics 2008-11-26 Ji-Rong Ren , Ran Li , Yi-Shi Duan

I discuss algorithms for the evaluation of Feynman integrals. These algorithms are based on Hopf algebras and evaluate the Feynman integral to (multiple) polylogarithms.

High Energy Physics - Theory · Physics 2007-05-23 Stefan Weinzierl

Let $f,g:M \rightarrow N$ be two maps between simply-connected smooth manifolds $M$ and $N$, such that $M$ is compact and $N$ is of finite $\mathbb{R}$-type. The goal of this paper is to use integration of certain differential forms to…

Algebraic Topology · Mathematics 2018-12-12 Felix Wierstra

Welschinger invariants of the real projective plane can be computed via the enumeration of enriched graphs, called marked floor diagrams. By a purely combinatorial study of these objects, we prove a Caporaso-Harris type formula which allows…

Algebraic Geometry · Mathematics 2010-04-29 Aubin Arroyo , Erwan Brugalle , Lucia Lopez de Medrano

We describe an algorithm which computes components of Humbert surfaces in terms of Rosenhain invariants, based on Runge's method

Number Theory · Mathematics 2007-11-28 David Gruenewald

We show that Hopf invariants, defined by evaluation in Harrison cohomology of the commutative cochains of a space, calculate the logarithm map from a fundamental group to its Malcev Lie algebra. They thus present the zeroth Harrison…

Algebraic Topology · Mathematics 2025-12-08 Nir Gadish , Aydin Ozbek , Dev Sinha , Ben Walter

We study numerical computation of conformal invariants of domains in the complex plane. In particular, we provide an algorithm for computing the conformal capacity of a condenser. The algorithm applies for wide kind of geometries: domains…

Complex Variables · Mathematics 2020-08-19 Mohamed M S Nasser , Matti Vuorinen

The classical Hopf invariant is defined for a map f: S^r -> X. Here we define `hcat' which is some kind of Hopf invariant built with a construction in Ganea's style, valid for maps not only on spheres but more generally on a `relative…

Algebraic Topology · Mathematics 2025-03-18 Jean-Paul Doeraene , Mohammed El Haouari