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Related papers: An equivariant index theorem for hypoelliptic oper…

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We define the Chern character of the index class of a $G$-invariant family of $G$-transversally elliptic operators, see [6]. Next we study the Berline-Vergne formula for families in the elliptic and transversally elliptic case.

K-Theory and Homology · Mathematics 2019-04-24 Alexandre Baldare

We establish necessary and sufficient conditions for the global hypoellipticity of $G$-invariant operators on homogeneous vector bundles. These criteria are established in terms of the corresponding matrix-valued symbols as developed by…

Analysis of PDEs · Mathematics 2024-03-27 Duván Cardona , André Pedroso Kowacs

Let $G$ be a finite abelian group acting faithfully on ${\mathbb C}{\mathbb P}^1$ via holomorphic automorphisms. In \cite{DF2} the $G$--equivariant algebraic vector bundles on $G$--invariant affine open subsets of ${\mathbb C}{\mathbb P}^1$…

Algebraic Geometry · Mathematics 2024-06-07 Indranil Biswas , Francois-Xavier Machu

We give a simple proof of the cobordism invariance of the index of an elliptic operator. The proof is based on a study of a Witten-type deformation of an extension of the operator to a complete Riemannian manifold. One of the advantages of…

Spectral Theory · Mathematics 2007-05-23 Maxim Braverman

Let $M$ be a spin manifold, the Dirac operator with coefficient in the universal flat Hilbert $C^\ast \pi_1(M)$-module determines a "Rosenberg index element" which, according to B.Hanke and T.Schick, subsumes the enlargeablility obstruction…

Differential Geometry · Mathematics 2023-02-15 Guangxiang Su , Zelin Yi

Boutet de Monvel's calculus provides a pseudodifferential framework which encompasses the classical differential boundary value problems. In an extension of the concept of Lopatinski and Shapiro, it associates to each operator two symbols:…

K-Theory and Homology · Mathematics 2018-11-28 Severino Melo , Elmar Schrohe , Thomas Schick

Equivariant versions of the radial index and of the GSV-index of a vector field or a 1-form on a singular variety with an action of a finite group are defined. They have values in the Burnside ring of the group. Poincar\'e-Hopf type…

Algebraic Geometry · Mathematics 2013-07-09 Wolfgang Ebeling , Sabir M. Gusein-Zade

For a compact Lie group G, we use G-equivariant Poincar\'e duality for ordinary RO(G)-graded homology to define an equivariant intersection product, the dual of the equivariant cup product. Using this, we give a homological construction of…

Algebraic Topology · Mathematics 2013-07-23 Philipp Wruck

In this paper we study the following question: do sub-Laplacian type operators have non-trivial index theory on Carnot manifolds in higher degree of nilpotency? The problem relates to characterizing the structure of the space of…

Analysis of PDEs · Mathematics 2025-01-29 Magnus Goffeng , Bernard Helffer

In the paper we consider the theory of elliptic operators acting in subspaces defined by pseudodifferential projections. This theory on closed manifolds is connected with the theory of boundary value problems for operators violating…

Differential Geometry · Mathematics 2015-06-26 A. Yu. Savin , B. Yu. Sternin

An analytic index is defined for a family of cusp pseudodifferential operators, $P_b,$ on a fibration with fibres which are compact manifolds with boundaries, provided the family is elliptic and has invertible indicial family at the…

Differential Geometry · Mathematics 2007-05-23 Richard Melrose , Frederic Rochon

Given a Lie group $G$ of quantized canonical transformations acting on the space $L^2(M)$ over a closed manifold $M$, we define an algebra of so-called $G$-operators on $L^2(M)$. We show that to $G$-operators we can associate symbols in…

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

Consider a proper, isometric action by a unimodular locally compact group $G$ on a Riemannian manifold $M$ with boundary, such that $M/G$ is compact. Then an equivariant Dirac-type operator $D$ on $M$ under a suitable boundary condition has…

K-Theory and Homology · Mathematics 2020-06-16 Peter Hochs , Bai-Ling Wang , Hang Wang

An index theory for projective families of elliptic pseudodifferential operators is developed when the twisting, i.e. Dixmier-Douady, class is decomposable. One of the features of this special case is that the corresponding Azumaya bundle…

Differential Geometry · Mathematics 2010-05-07 V. Mathai , R. B. Melrose , I. M. Singer

Let $G$ be a compact Lie group that acts smoothly on a closed manifold $M$. Using a general Simonenko principle, we derive a novel criterion for the Fredholm property of $G$-pseudodifferential operators acting on Sobolev spaces of sections…

Differential Geometry · Mathematics 2026-05-15 Alexandre Baldare , Anton Yu. Savin , Elmar Schrohe

In this paper, we investigate topological aspects of indices of twisted geometric operators on manifolds equipped with fibered boundaries. We define $K$-groups relative to the pushforward for boundary fibration, and show that indices of…

K-Theory and Homology · Mathematics 2020-01-08 Mayuko Yamashita

The relative index theorem is proved for general first-order elliptic operators that are complete and coercive at infinity over measured manifolds. This extends the original result by Gromov-Lawson for generalised Dirac operators as well as…

Analysis of PDEs · Mathematics 2022-10-31 Lashi Bandara

We consider the equivariant K-theory of a real semisimple Lie group which acts on the (complex) flag variety of its complexification group. We construct an assemble map in the framework of KK-theory and then we prove that it is an…

K-Theory and Homology · Mathematics 2021-03-09 Zhaoting Wei

We give a Riemannian structure to the set $\Sigma$ of positive invertible unitized Hilbert-Schmidt operators, by means of the trace inner product. This metric makes of $\Sigma$ a nonpositively curved, simply connected and metrically…

Differential Geometry · Mathematics 2008-08-20 Gabriel Larotonda

Let G be a Lie group, $T^*G$ its cotangent bundle with its natural Lie group structure obtained by performing a left trivialization of T^*G and endowing the resulting trivial bundle with the semi-direct product, using the coadjoint action…

Differential Geometry · Mathematics 2015-04-29 Andre Diatta , Bakary Manga
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