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Related papers: Twisted Lefschetz number and Nielsen number

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Let X be a smooth algebraic variety over a field of characteristic 0. We introduce the notion of twisted associative (resp. Poisson) deformation of the structure sheaf O_X. These are stack-like versions of usual deformations. We prove that…

Algebraic Geometry · Mathematics 2011-07-28 Amnon Yekutieli

Let $S$ be a complex projective surface. Lefschetz originally proved Lefschetz $(1, 1)$--Theorem by studying a Lefschetz pencil of hyperplane sections of $S$ and the Abel--Jacobi mapping. In this paper, we attack Lefschetz $(1, 1)$--Theorem…

Algebraic Geometry · Mathematics 2022-05-25 Erjuan Fu

Let $F$ be a smooth foliation on a closed Riemannian manifold $M$, and let $\Lambda$ be a transverse invariant measure of $F$. Suppose that $\Lambda$ is absolutely continuous with respect to the Lebesgue measure on smooth transversals. Then…

Geometric Topology · Mathematics 2008-01-31 Jesús A. Álvarez López , Yuri A. Kordyukov

We propose and study a variation of the classical isomorphism problem for group rings in the context of projective representations. We formulate several weaker conditions following from our notion and give all logical connections between…

Rings and Algebras · Mathematics 2025-10-23 Leo Margolis , Ofir Schnabel

The purpose of the present paper is to discuss the following conjecture of Fel'shtyn and Hill, which is a generalization of the classical Burnside theorem: Let G be a countable discrete group, f its automorphism, R(f) the number of…

Representation Theory · Mathematics 2016-09-07 Alexander Fel'shtyn , Evgenij Troitsky , Anatoly Vershik

We generalize graded Hecke algebras to include a twisting two-cocycle for the associated finite group. We give examples where the parameter spaces of the resulting twisted graded Hecke algebras are larger than that of the graded Hecke…

Representation Theory · Mathematics 2007-05-23 Sarah J. Witherspoon

We extend the Nielsen theory of coincidence sets to equalizer sets, the points where a given set of (more than 2) mappings agree. On manifolds, this theory is interesting only for maps between spaces of different dimension, and our results…

General Topology · Mathematics 2012-04-24 P. Christopher Staecker

In classical fixed point and coincidence theory the notion of Nielsen numbers has proved to be extremely fruitful. Here we extend it to pairs (f_1, f_2) of maps between manifolds of arbitrary dimensions. This leads to estimates of the…

Algebraic Topology · Mathematics 2007-05-23 Ulrich Koschorke

In the paper we introduce the notion of twisted derivation of a bialgebra. Twisted derivations appear as infinitesimal symmetries of the category of representations. More precisely they are infinitesimal versions of twisted automorphisms of…

Quantum Algebra · Mathematics 2012-04-24 Alexei Davydov

We consider the Reeb graph of a thickening of points sampled from an unknown space. Our main contribution is a framework to transfer reconstruction results similar to the well-known work of Niyogi, Smale, and Weinberger to the setting of…

Computational Geometry · Computer Science 2025-12-10 Håvard Bakke Bjerkevik , Nello Blaser , Lars M. Salbu

Let $Y \to E \stackrel{p}{\to} B$ be a fibration and let $f: E \to E$ be a fiber map over $B$. In this work, we study the geometric and algebraic Reidemeister classes of the iterates of $f$ and introduce a Nielsen-type periodic number over…

Algebraic Topology · Mathematics 2024-11-21 Weslem Liberato Silva , Rafael Moreira de Souza

We find the subgroup of classical acceleration-enlarged Newton-Hooke Hopf algebra which acts covariantly on the twisted acceleration-enlarged Newton-Hooke space-times. The case of classical acceleration-enlarged Galilei quantum group is…

Mathematical Physics · Physics 2012-11-30 Marcin Daszkiewicz

The aim of this work is to investigate the structure of some skew twisted algebras, when the coefficient ring is a localization of the polynomial ring over the field of characteristic zero, and an involution is provided. A parallel…

Rings and Algebras · Mathematics 2020-11-12 Natalia Golovashchuk , João Schwarz

This paper introduces the notion of twisted toric manifolds which is a generalization of one of symplectic toric manifolds, and proves the weak Delzant type classification theorem for them. The computation methods for their fundamental…

Symplectic Geometry · Mathematics 2007-05-23 Takahiko Yoshida

Twisted modules over vertex algebras formalize the relations among twisted vertex operators and have applications to conformal field theory and representation theory. A recent generalization, called twisted logarithmic module, involves the…

Quantum Algebra · Mathematics 2024-01-03 Bojko Bakalov , McKay Sullivan

Given a finite-dimensional Lie algebra, and a representation by derivations on the completed symmetric algebra of its dual, a number of interesting twisted constructions appear: certain twisted Weyl algebras, deformed Leibniz rules,…

Quantum Algebra · Mathematics 2011-11-10 Stjepan Meljanac , Zoran Škoda

Twisted symmetries, widely studied in the last decade, proved to be as effective as standard ones in the analysis and reduction of nonlinear equations. We explain this effectiveness in terms of a Lie-Frobenius reduction; this requires to…

Mathematical Physics · Physics 2015-10-20 Giuseppe Gaeta

We establish a priori Lipschitz estimates for equations with mixed local and nonlocal diffusion, coercive gradient terms and unbounded right-hand side in Lebesgue spaces through an integral refinement of the Bernstein method. This relies on…

Analysis of PDEs · Mathematics 2022-08-01 Alessandro Goffi

The Lefschetz fixed point theorem follows easily from the identification of the Lefschetz number with the fixed point index. This identification is a consequence of the functoriality of the trace in symmetric monoidal categories. There are…

Algebraic Topology · Mathematics 2014-02-25 Kate Ponto

We describe the twist quantization of string worldsheet theory, which unifies the description of quantization and the target space symmetry, based on the twisting of Hopf and module algebras. We formulate a method of decomposing a twist…

High Energy Physics - Theory · Physics 2011-03-28 Tsuguhiko Asakawa , Satoshi Watamura