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Related papers: A short proof of an index theorem, II

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We establish an index theorem for Toeplitz operators on odd dimensional spin manifolds with boundary. It may be thought of as an odd dimensional analogue of the Atiyah-Patodi-Singer index theorem for Dirac operators on manifolds with…

Differential Geometry · Mathematics 2007-05-23 Xianzhe Dai , Weiping Zhang

We prove an index formula for the Dirac operator acting on two-valued spinors on a $3$-manifold $M$ which branch along a smoothly embedded graph $\Sigma \subset M$, and with respect to a boundary condition along $\Sigma$ inspired by an…

Differential Geometry · Mathematics 2025-12-04 Andriy Haydys , Rafe Mazzeo , Ryosuke Takahashi

We give a detailed and unified survey of equivariant $KK$-theory over locally compact, second countable, locally Hausdorff groupoids. We indicate precisely how the "classical" proofs relating to the Kasparov product can be used almost…

K-Theory and Homology · Mathematics 2020-06-24 Lachlan MacDonald

Positiveness of scalar curvature and Ricci curvature requires vanishing the obstruction $\theta(M)$ which is computed in some KK-theory of C*-algebras index as a pairing of spin Dirac operator and Mishchenko bundle associated to the…

K-Theory and Homology · Mathematics 2017-05-09 Do Ngoc Diep

We give a systematic treatment of index theory on Pin manifolds, based on the Clifford linear Dirac operator and differential KO-theory. This expository article is based on joint work with Mike Hopkins.

Differential Geometry · Mathematics 2024-07-26 Daniel S. Freed

A Dirac-type operator on a complete Riemannian manifold is of Callias-type if its square is a Schr\"{o}dinger-type operator with a potential uniformly positive outside of a compact set. We develop the theory of Callias-type operators…

Differential Geometry · Mathematics 2018-03-28 Simone Cecchini

We mathematically show an equality between the index of a Dirac operator on a flat continuum torus and the $\eta$ invariant of a lattice Dirac operator known as the Wilson Dirac operator with a negative mass when the lattice spacing is…

K-Theory and Homology · Mathematics 2025-06-03 Shoto Aoki , Hidenori Fukaya , Mikio Furuta , Shinichiroh Matsuo , Tetsuya Onogi , Satoshi Yamaguchi

Using Weitzenb\"ock techniques on any compact Riemannian spin manifold we derive inequalities that involve a real parameter and join the eigenvalues of the Dirac operator with curvature terms. The discussion of these inequalities yields…

Differential Geometry · Mathematics 2009-11-10 K. -D. Kirchberg

In this paper we prove a relative index theorem for pairs of generalized Dirac operators on orbifolds which are the same at infinity. This generalizes to orbifolds a celebrated theorem of Gromov and Lawson.

Differential Geometry · Mathematics 2015-06-26 Carla Farsi

Let X be a compact manifold with boundary, and suppose that the boundary is the total space of a fibration with base Y and fibre Z. Let D be a generalized Dirac operator associated to a Phi-metric g on X. Under the assumption that D is…

Differential Geometry · Mathematics 2007-05-23 Eric Leichtnam , Rafe Mazzeo , Paolo Piazza

In this expository paper, we explain a formula for the multiplicities of the index of an equivariant transversally elliptic operator on a $G$-manifold. The formula is a sum of integrals over blowups of the strata of the group action and…

Differential Geometry · Mathematics 2021-01-28 Jochen Brüning , Franz W. Kamber , Ken Richardson

The equivariant coarse index is well-understood and widely used for actions by discrete groups. We extend the definition of this index to general locally compact groups. We use a suitable notion of admissible modules over $C^*$-algebras of…

K-Theory and Homology · Mathematics 2022-07-05 Hao Guo , Peter Hochs , Varghese Mathai

In order to facilitate the comparison of Riemannian homogeneous spaces of compact Lie groups with noncommutative geometries ("quantizations") that approximate them, we develop here the basic facts concerning equivariant vector bundles and…

Differential Geometry · Mathematics 2008-11-14 Marc A. Rieffel

The construction of topological index maps for equivariant families of Dirac operators requires factoring a general smooth map through maps of a very simple type: zero sections of vector bundles, open embeddings, and vector bundle…

K-Theory and Homology · Mathematics 2012-06-29 Ralf Meyer , Heath Emerson

Along the lines of the classic Hodge-De Rham theory a general decomposition theorem for sections of a Dirac bundle over a compact Riemannian manifold is proved by extending concepts as exterior derivative and coderivative as well as as…

Differential Geometry · Mathematics 2020-08-13 Simone Farinelli

In this paper, we get the Kastler-Kalau-Walze theorem associated to Dirac operators with torsion on compact manifolds with boundary. We give two kinds of operator-theoretic explanations of the gravitational action in the case of…

Mathematical Physics · Physics 2015-05-29 Jian Wang , Yong Wang , ChunLing Yang

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 Fredholm properties and index formulas for Dirac operators over complete Riemannian manifolds with straight ends. An important class of examples of such manifolds are complete Riemannian manifolds with pinched negative sectional…

Differential Geometry · Mathematics 2019-02-20 Werner Ballmann , Jochen Brüning , Gilles Carron

We obtain a vanishing theorem for the kernel of a Dirac operator on a Clifford module twisted by a sufficiently large power of a line bundle, whose curvature is non-degenerate at any point of the base manifold. In particular, if the base…

Differential Geometry · Mathematics 2007-05-23 Maxim Braverman

We extend several classical eigenvalue estimates for Dirac operators on compact manifolds to noncompact, even incomplete manifolds. This includes Friedrich's estimate for manifolds with positive scalar curvature as well as the author's…

Differential Geometry · Mathematics 2009-07-16 Christian Baer