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Related papers: Witten deformation and the equivariant index

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We introduce a geometric invariant that we call the index of symmetry, which measures how far is a Riemannian manifold from being a symmetric space. We compute, in a geometric way, the index of symmetry of compact naturally reductive…

Differential Geometry · Mathematics 2013-02-14 Carlos Olmos , Silvio Reggiani , Hiroshi Tamaru

Irreducible representations of both Leavitt and Cohn path algebras of an arbitrary digraph with coefficients in a commutative field is classified. They are constructed in several ways using both infinite paths on the right as well as direct…

Rings and Algebras · Mathematics 2019-03-25 P. N. Anh , T. G. Nam

We suggest a new algorithm to estimate representations of compact Lie groups from finite samples of their orbits. Different from other reported techniques, our method allows the retrieval of the precise representation type as a direct sum…

Optimization and Control · Mathematics 2025-09-23 Henrique Ennes , Raphaël Tinarrage

We develop a geometric version of the inverse problem of the calculus of variations for discrete mechanics and constrained discrete mechanics. The geometric approach consists of using suitable Lagrangian and isotropic submanifolds. We also…

Differential Geometry · Mathematics 2018-05-09 María Barbero-Liñán , Marta Farré Puiggalí , Sebastián Ferraro , David Martín de Diego

The geometrical representation of the path integral reduction Jacobian obtained in the problem of the path integral quantization of a scalar particle motion on a smooth compact Riemannian manifold with the given free isometric action of the…

Mathematical Physics · Physics 2015-05-13 S. N. Storchak

We study Wick-rotations of left-invariant metrics on Lie groups, using results from real GIT (\cite{1}, \cite{2}, \cite{3}). An invariant for Wick-rotation of Lie groups is given, and we describe when a pseudo-Riemannian Lie group can be…

Differential Geometry · Mathematics 2020-09-08 Christer Helleland

The Unified Transform provides a novel method for analyzing boundary value problems for linear and for integrable nonlinear PDEs. The numerical implementation of this method to linear elliptic PDEs formulated in the {\it interior} of a…

Analysis of PDEs · Mathematics 2014-01-14 A. S. Fokas , J. Lenells

We introduce a new class of natural, explicitly defined, transversally elliptic differential operators over manifolds with compact group actions. Under certain assumptions, the symbols of these operators generate all the possible values of…

Differential Geometry · Mathematics 2021-01-28 Igor Prokhorenkov , Ken Richardson

We compare the deformation theory and the analytic structure of the Seiberg-Witten moduli spaces of a K\"ahler surface to the corresponding components of the Hilbert scheme, and show that they are isomorphic. Next we show how to compute the…

alg-geom · Mathematics 2008-02-03 Robert Friedman , John W. Morgan

We derive a complete asymptotic expansion of generalized Witten integrals for Hamiltonian circle actions on arbitrary symplectic manifolds, characterizing the coefficients in the expansion as integrals over the symplectic strata of the…

Symplectic Geometry · Mathematics 2021-03-19 Benjamin Küster , Pablo Ramacher

Equivariant indices have previously been defined in cases where either the group or the orbit space in question is compact. In this paper, we develop an equivariant index without assuming the group or the orbit space to be compact. This…

K-Theory and Homology · Mathematics 2016-09-06 Peter Hochs , Yanli Song

We construct a decomposition of the identity operator on a Riemannian manifold $M$ as a sum of smooth orthogonal projections subordinate to an open cover of $M$. This extends a decomposition of the real line by smooth orthogonal projection…

Classical Analysis and ODEs · Mathematics 2018-03-12 Marcin Bownik , Karol Dziedziul , Anna Kamont

Let $B$ be a ring, not necessarily commutative, having an involution $*$ and let ${\mathrm U}_{2m}(B)$ be the unitary group of rank $2m$ associated to a hermitian or skew hermitian form relative to $*$. When $B$ is finite, we construct a…

Representation Theory · Mathematics 2019-06-11 James Cruickshank , Luis Gutiérrez Frez , Fernando Szechtman

A representation of the central extension of the unitary Lie algebra coordinated with a skew Laurent polynomial ring is constructed using vertex operators over an integral Z_2-lattice. The irreducible decomposition of the representation is…

Quantum Algebra · Mathematics 2021-03-17 Fulin Chen , Yun Gao , Naihuan Jing , Shaobin Tan

The main result of this paper is a formula for calculating the Seiberg-Witten invariants of 4-manifolds with fixed-point free circle actions. This is done by showing under suitable conditions the existence of a diffeomorphism between the…

Geometric Topology · Mathematics 2007-05-23 Scott Baldridge

We discuss a peculiar interplay between the representation theory of the holonomy group of a Riemannian manifold, the Weitzenboeck formula for the Hodge-Laplace operator on forms and the Lichnerowicz formula for twisted Dirac operators. For…

Differential Geometry · Mathematics 2007-05-23 Uwe Semmelmann , Gregor Weingart

We develop a formula for the equivariant index of a twisted Dirac operator on a compact globally hyperbolic spacetime with timelike boundary on which a group acts isometrically, subject to APS boundary conditions. The formula is the same as…

Differential Geometry · Mathematics 2026-02-19 Onirban Islam , Lennart Ronge

In this paper, we define locally convex vector spaces of weighted vector fields and use them as model spaces for Lie groups of weighted diffeomorphisms on Riemannian manifolds. We prove an easy condition on the weights that ensures that…

Differential Geometry · Mathematics 2016-01-13 Boris Walter

Let $G(\mathbb{R})$ be a real reductive group. Suppose $\pi$ is an irreducible representation of $G(\mathbb{R})$ having a Whittaker model, and consider three invariants of $\pi$ related to nilpotents elements of the Lie algebra of $G$ (or…

Representation Theory · Mathematics 2026-04-29 Jeffrey Adams , Alexandre Afgoustidis

We compute, by two methods, the genus one degree zero orbifold Gromov-Witten invariants with non-stacky insertions which are exceptional cases of the dilaton and divisor equations. One method involves a detailed analysis of the relevant…

Algebraic Geometry · Mathematics 2012-04-13 Hsian-Hua Tseng