English
Related papers

Related papers: Twisted Lefschetz number and Nielsen number

200 papers

Hurwitz numbers enumerate branched morphisms between Riemann surfaces. For a fixed elliptic target, Hurwitz numbers are intimately related to mirror symmetry following work of Dijkgraaf. In recent work of Chapuy and Dolega a new variant of…

Combinatorics · Mathematics 2024-10-28 Marvin Anas Hahn , Hannah Markwig

The Lefschetz fixed point theorem and its converse have many generalizations. One of these generalizations is to endomorphisms of a space relative to a fixed subspace. In this paper we define relative Lefschetz numbers and Reidemeister…

Algebraic Topology · Mathematics 2014-10-01 Kate Ponto

Given two maps between smooth manifolds, the obstruction to removing their coincidences (via homotopies) is measured by minimum numbers. In order to determine them we introduce and study an infinite hierarchy of Nielsen numbers N_i, i = 0,…

Algebraic Topology · Mathematics 2014-10-01 Ulrich Koschorke

Suppose X,Y are manifolds, f,g:X->Y are maps. The well-known Coincidence Problem studies the coincidence set C={x:f(x)=g(x)}. The number m=dimX-dimY is called the codimension of the problem. More general is the Preimage Problem. For a map…

Geometric Topology · Mathematics 2007-05-23 Peter Saveliev

We study the set of points returning infinitely often to a sequence of targets dependent on the starting points. With an assumption of decay of correlations for L1 against bounded variations, we prove a generalized quantitative recurrence…

Dynamical Systems · Mathematics 2023-01-13 Jiajie Zheng

The reduced Lefschetz number, that is, the Lefschetz number minus 1, is proved to be the unique integer-valued function L on selfmaps of compact polyhedra which is constant on homotopy classes such that (1) L(fg) = L(gf), for f:X -->Y and…

Algebraic Topology · Mathematics 2007-05-23 Martin Arkowitz , Robert F. Brown

Twisted Toeplitz matrices constitute a generalization of Toeplitz matrices in the sense that the entries on each diagonal no longer need to be constant, but are given by the values of a continuous function on a partition of $[0,1]$. We…

Probability · Mathematics 2026-04-23 Dario Giandinoto , Boris Shapiro

The Fourier(-Stieltjes) algebras on locally compact groups are important commutative Banach algebras in abstract harmonic analysis. In this paper we introduce a generalization of the above two algebras via twisting with respect to…

Operator Algebras · Mathematics 2025-08-13 Hun Hee Lee , Xiao Xiong

Let X be a smooth algebraic variety over a field K containing the real numbers. We introduce the notion of twisted associative (resp. Poisson) deformation of the structure sheaf of X. These are stack-like versions of usual deformations. We…

Algebraic Geometry · Mathematics 2014-09-08 Amnon Yekutieli

We study twisted conjugacy classes of the unit element in different groups. Fel'shtyn and Troitsky showed that the twisted conjugacy class of the unit element of an abelian group is a subgroup for every automorphism. The structure is…

Group Theory · Mathematics 2013-03-07 V. G. Bardakov , T. R. Nasybullov , M. V. Neshchadim

We investigate a class of Leibniz algebroids which are invariant under diffeomorphisms and symmetries involving collections of closed forms. Under appropriate assumptions we arrive at a classification which in particular gives a…

Differential Geometry · Mathematics 2012-02-21 David Baraglia

In [8,9], the authors developed a nice formula to compute the Nielsen number of a self-map on an infra-nilmanifold. For the case of nilmanifolds this formula was extended to $n$-valued maps in [4]. In this paper, we extend these results…

Algebraic Topology · Mathematics 2026-03-05 Karel Dekimpe , Lore De Weerdt

We define group-twisted Alexander-Whitney and Eilenberg-Zilber maps for converting between bimodule resolutions of skew group algebras. These algebras are the natural semidirect products recording actions of finite groups by automorphisms.…

Rings and Algebras · Mathematics 2020-04-30 A. V. Shepler , S. Witherspoon

Classically, the exponent of a group is the least common multiple of the orders of its elements. This notion was generalized by Etingof and Gelaki to the context of Hopf algebras. Kashina, Sommerhauser and Zhu later observed that there is a…

Quantum Algebra · Mathematics 2017-01-03 Daniel S. Sage , Maria D. Vega

We show that the baryon number of N=2 supersymmetric QCD can be twisted in order to couple the topological field theory of non-abelian monopoles to $Spin^c$-structures. To motivate the construction, we also consider some aspects of the…

High Energy Physics - Theory · Physics 2009-10-30 J. M. F. Labastida , M. Marino

We use twisted sheaves and their moduli spaces to study the Brauer group of a scheme. In particular, we (1) show how twisted methods can be efficiently used to re-prove the basic facts about the Brauer group and cohomological Brauer group…

Algebraic Geometry · Mathematics 2018-06-18 Max Lieblich

The algebra B of bicomplex numbers is viewed as a complexification of the Archimedean f-algebra of hyperbolic numbers D. This lattice-theoretic approach allows us to establish new properties of the so-called D-norms. In particular, we show…

Functional Analysis · Mathematics 2023-06-22 Hichem Gargoubi , Sayed Kossentini

In classical fixed point and coincidence theory the notion of Nielsen numbers has proved to be extremely fruitful. We extend it to pairs (f_1,f_2) of maps between manifolds of arbitrary dimensions, using nonstabilized normal bordism theory…

Algebraic Topology · Mathematics 2009-03-01 Ulrich Koschorke

Let $G$ be the group of complex points of a real semi-simple Lie group whose fundamental rank is equal to 1, e.g. $G= \SL_2 (\C) \times \SL_2 (\C)$ or $\SL_3 (\C)$. Then the fundamental rank of $G$ is $2,$ and according to the conjecture…

Number Theory · Mathematics 2016-03-10 Nicolas Bergeron , Michael Lipnowski

Restricted twisted Heisenberg Lie superalgebras are studied over an algebraically closed field F of characteristic p > 0. We determine the restricted structures and use the ordinary 1- and 2-cohomology spaces with trivial coefficients to…

Rings and Algebras · Mathematics 2025-09-04 Yong Yang