English
Related papers

Related papers: $L^2$-index formula for proper cocompact group act…

200 papers

We formulate, for any Lie group G acting isometrically on a manifold M, the general notion of a G-equivariant elliptic operator that is invertible outside of a G-cocompact subset of M. We prove a version of the Rellich lemma for this…

Differential Geometry · Mathematics 2024-09-02 Hao Guo

We study the core of a proper action by a Lie group $G$ on a smooth manifold $M$, extending the construction for $G$ compact by Skjelbred and Straume. Moreover, we show that many properties of a proper $G$-action on $M$ are determined by…

Differential Geometry · Mathematics 2025-09-25 Leonardo Biliotti , Gustavo May Custodio , Alessandro Minuzzo

For a simple real Lie group $G$ with Heisenberg parabolic subgroup $P$, we study the corresponding degenerate principal series representations. For a certain induction parameter the kernel of the conformally invariant system of second order…

Representation Theory · Mathematics 2024-04-25 Jan Frahm

We prove the Fredholmness of Dirac operators of monopoles with Dirac-type singularities on oriented complete Riemannian $3$-folds, and we also calculate the $L^2$-indices of them.

Differential Geometry · Mathematics 2019-10-23 Masaki Yoshino

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 present an invariant definition of the hypoelliptic Laplacian on sub-Riemannian structures with constant growth vector, using the Popp's volume form introduced by Montgomery. This definition generalizes the one of the Laplace-Beltrami…

Analysis of PDEs · Mathematics 2009-09-29 Andrei Agrachev , Ugo Boscain , Jean-Paul Gauthier , Francesco Rossi

We compute explicitly, and without any extra regularity assumptions, the large time limit of the fibrewise heat operator for Bismut-Lott type superconnections in the L^2-setting. This is motivated by index theory on certain non-compact…

Differential Geometry · Mathematics 2015-07-16 Sara Azzali , Sebastian Goette , Thomas Schick

We study the quantum dynamics of a system of $n$ Abelian ${\cal N}=1$ vector multiplets coupled to $\frac 12 n(n+1)$ chiral multiplets which parametrise the Hermitian symmetric space $\mathsf{Sp}(2n, {\mathbb R})/ \mathsf{U}(n)$. In the…

High Energy Physics - Theory · Physics 2023-07-05 Darren T. Grasso , Sergei M. Kuzenko

In this expository article, we consider first order elliptic differential operators acting on smooth vector bundles over compact manifolds, and certain invariants derived from the analysis of these operators, namely the eta invariant} and…

Differential Geometry · Mathematics 2019-08-15 Jochen Brüning , Ken Richardson

This paper, together with Part II, expands the results of math.DG/9803051. In Part I we study the twisted index theory of elliptic operators on orbifold covering spaces of compact good orbifolds, which are invariant under a projective…

Differential Geometry · Mathematics 2007-05-23 Matilde Marcolli , Varghese Mathai

We study Dirac-type operators on incomplete cusp edge spaces with invertible boundary families. In particular, we construct the heat kernel for the associated Laplace-type operator and prove that the Dirac operators are essentially…

Differential Geometry · Mathematics 2025-08-05 Jayson Liu

We will discuss the equivariant cohomology of a manifold endowed with the action of a Lie group. Localization formulae for equivariant integrals are explained by a vanishing theorem for equivariant cohomology with generalized coefficients.…

Differential Geometry · Mathematics 2007-05-23 Michele Vergne

We study differential operators on complete Riemannian manifolds which act on sections of a bundle of finite type modules over a von Neumann algebra with a trace. We prove a relative index and a Callias-type index theorems for von Neumann…

Differential Geometry · Mathematics 2016-02-23 Maxim Braverman , Simone Cecchini

We define a representation of the unitary group $U(n)$ by metaplectic operators acting on $L^2(\mathbb{R}^n)$ and consider the operator algebra generated by the operators of the representation and pseudodifferential operators of Shubin…

Operator Algebras · Mathematics 2020-08-04 Anton Savin , Elmar Schrohe

We introduce a new integral representation for the standard L-function of an irreducible cuspidal automorphic representation of the exceptional group G2, and also for the twist of this L-function by an arbitrary character. Because our…

Representation Theory · Mathematics 2012-10-16 David Ginzburg , Joseph Hundley

This article gives an up-to-date account of the theory of discrete group actions on non-Riemannian homogeneous spaces. As an introduction of the motifs of this article, we begin by reviewing the current knowledge of possible global forms of…

Differential Geometry · Mathematics 2011-06-23 Toshiyuki Kobayashi

The $L^2$-Index Theorem of Atiyah \cite{atiyah} expresses the index of an elliptic operator on a closed manifold $M$ in terms of the $G$-equivariant index of some regular covering $\widetilde{M}$ of $M$, with $G$ the group of covering…

K-Theory and Homology · Mathematics 2010-04-09 Indira Chatterji , Guido Mislin

Let G be a real reductive Lie group and H a closed reductive subgroup of G. We investigate the deformation of "standard" compact quotients of G/H, i.e., of quotients of G/H by discrete subgroups Gamma of G that are uniform lattices in a…

Group Theory · Mathematics 2009-11-24 Fanny Kassel

The starting point of our analysis is an old idea of writing an eigenfunction expansion for a heat kernel considered in the case of a hypoelliptic heat kernel on a nilpotent Lie group $G$. One of the ingredients of this approach is the…

Differential Geometry · Mathematics 2016-02-04 Malva Asaad , Maria Gordina

Let D be a holomorphic differential operator acting on sections of a holomorphic vector bundle on an n-dimensional compact complex manifold. We prove a formula, conjectured by Feigin and Shoikhet, for the Lefschetz number of D as the…

Quantum Algebra · Mathematics 2008-02-12 Markus Engeli , Giovanni Felder