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Related papers: Note on MacPherson's local Euler obstruction

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Suppose one is given a discrete group G, a cocompact proper G-manifold M, and a G-self-map f of M. Then we introduce the equivariant Lefschetz class of f, which is globally defined in terms of cellular chain complexes, and the local…

Algebraic Topology · Mathematics 2011-04-14 Wolfgang Lueck , Jonathan Rosenberg

Let $A$ and $B$ be compact operators over a topological space $X$ and suppose that these operators are normal and have same distinct eigenvalues at each point. By obstruction theory, we establish a necessary and sufficient condition for $A$…

Functional Analysis · Mathematics 2017-09-04 Jingming Zhu

The purpose of this short note is to prove a formula for the Chern-Mather classes of a toric variety in terms of its orbits and the local Euler obstructions at general points of each orbit (Theorem 2). We use the general definition of the…

Algebraic Geometry · Mathematics 2016-04-12 Ragni Piene

The article consists of a survey on analytic and topological torsion. Analytic torsion is defined in terms of the spectrum of the analytic Laplace operator on a Riemannian manifold, whereas topological torsion is defined in terms of a…

Geometric Topology · Mathematics 2015-11-10 Wolfgang Lueck

We introduce the notion of equivariant basic cohomology for singular Riemannian foliations with transverse infinitesimal actions, and prove some elementary properties such as its invariance under homotopies. For the particular case of…

Differential Geometry · Mathematics 2023-06-21 Francisco C. Caramello

We present a convergence theory for Optimized Schwarz Methods that rely on a non-local exchange operator and covers the case of coercive possibly non-self-adjoint impedance operators. This analysis also naturally deals with the presence of…

Numerical Analysis · Mathematics 2022-08-19 Xavier Claeys

For the undamped Kepler potential the lack of precession has historically been understood in terms of the Runge-Lenz symmetry. For the damped Kepler problem this result may be understood in terms of the generalization of Poisson structure…

Classical Physics · Physics 2023-03-03 P. M. Hamilton , M. Crescimanno

We study local-global principles for two notions of semi-integral points, termed Campana points and Darmon points. In particular, we develop a semi-integral version of the Brauer-Manin obstruction interpolating between Manin's classical…

Number Theory · Mathematics 2025-11-07 Vladimir Mitankin , Masahiro Nakahara , Sam Streeter

Using a generalized coordinate along with a proper invertible coordinate transformation, we show that the Euler-Lagrange equation used by Bagchi et al. 16 is in clear violation of the Hamilton's principle. We also show that Newton's…

Classical Physics · Physics 2013-09-17 Omar Mustafa

We derive a local index theorem in Quillen's form for families of Cauchy-Riemann operators on orbifold Riemann surfaces (or Riemann orbisurfaces) that are quotients of the hyperbolic plane by the action of cofinite finitely generated…

Algebraic Geometry · Mathematics 2024-04-19 Leon A. Takhtajan , Peter Zograf

Motivated by a 1993 conjecture of Stanley and Stembridge, Shareshian and Wachs conjectured that the characteristic map takes the dot action of the symmetric group on the cohomology of a regular semisimple Hessenberg variety to $\omega…

Algebraic Geometry · Mathematics 2018-03-06 Patrick Brosnan , Timothy Y. Chow

Let M be a complete orientable manifold of bounded geometry. Suppose that M has finitely many ends, each having a neighborhood quasi-isometric to a neighborhood of an end of an infinite cyclic covering of a compact manifold. We consider a…

Differential Geometry · Mathematics 2007-05-23 John G. Miller

We propose a new method for defining a notion of support for objects in any compactly generated triangulated category admitting small coproducts. This approach is based on a construction of local cohomology functors on triangulated…

K-Theory and Homology · Mathematics 2008-02-12 Dave Benson , Srikanth B. Iyengar , Henning Krause

The Lagrangian formulation of classical mechanics is widely applicable in solving a vast array of physics problems encountered in the undergraduate and graduate physics curriculum. Unfortunately, many treatments of the topic lack…

Classical Physics · Physics 2026-04-14 Gerd Wagner , Matthew W. Guthrie

We give a geometrical interpretation for the principle of stationary action in classical Lagrangian particle mechanics. In a nutshell, the difference of the action along a path and its variation effectively ``counts'' the possible…

Classical Physics · Physics 2023-08-15 Gabriele Carcassi , Christine A. Aidala

In this paper we study the BPS state counting in the geometry of local obstructed curve with normal bundle O+O(-2). We find that the BPS states have a framed quiver description. Using this quiver description along with the Seiberg duality…

High Energy Physics - Theory · Physics 2010-05-27 Wu-yen Chuang , Guang Pan

We determine the relation between the local Euler obstruction $Eu_f$ of a holomorphic function $f$ and different generalizations of the Milnor number for functions on singular spaces.

Complex Variables · Mathematics 2007-05-23 Jose Seade , Mihai Tibar , Alberto Verjovsky

A torsor under a k-group scheme G on a variety X over a number field k imposes a descent obstruction against the existence of rational points on X. We discuss the finite descent obstruction, that is for all such torsors under finite…

Algebraic Geometry · Mathematics 2010-05-27 David Harari , Jakob Stix

Several types of generically-nondegenerate Poisson structures can be effectively studied as symplectic structures on naturally associated Lie algebroids. Relevant examples of this phenomenon include log-, elliptic, $b^k$-, scattering and…

Symplectic Geometry · Mathematics 2020-11-30 Ralph L. Klaasse

A series of recent papers by Bergfalk, Lupini and Panagiotopoulus developed the foundations of a field known as `definable algebraic topology,' in which classical cohomological invariants are enriched by viewing them as groups with a Polish…

Logic · Mathematics 2025-07-21 Nicholas Meadows