English
Related papers

Related papers: Eta cocycles

200 papers

We define a class of boundary value problems on manifolds with fibered boundary. This class is in a certain sense a deformation between the classical boundary value problems and the Atiyah-Patodi-Singer problems in subspaces. The boundary…

Operator Algebras · Mathematics 2007-05-23 A. Yu. Savin , B. Yu. Sternin

We introduce the vertical \(\widehat{A}\)-cowaist, a codimension-one invariant for partitioned manifolds. It extends the concept of infinite vertical \(\widehat{A}\)-cowaist for bands to arbitrary partitioned manifolds, which may be…

Differential Geometry · Mathematics 2026-05-19 Daoqiang Liu

We present the solution of a longstanding internal problem of noncommutative geometry, namely the computation of the index of a transversally elliptic operator on an arbitrary foliation. The new and crucial ingredient is a certain Hopf…

Differential Geometry · Mathematics 2009-10-31 Alain Connes , Henri Moscovici

In this paper we show that there is a well defined modified dbar-Neumann problem for a spin_c manifold with a strictly pseudoconvex boundary (in the contact geometry sense). We show that the index of the associated boundary value problem…

Analysis of PDEs · Mathematics 2007-05-23 Charles L. Epstein

In this paper we consider a family of Dirac-type operators on fibration $P \to B$ equivariant with respect to an action of an etale groupoid. Such a family defines an element in the bivariant $K$ theory. We compute the action of the…

Differential Geometry · Mathematics 2007-05-23 Alexander Gorokhovsky

We introduce a slight modification of the usual equivariant $KK$-theory. We use this to give a $KK$-theoretical proof of an equivariant index theorem for Dirac-Schrodinger operators on a non-compact manifold of nowhere positive curvature.…

K-Theory and Homology · Mathematics 2023-06-28 Y. Abdolmaleki , D. Kucerovsky

We show that the Wilson Dirac operator in lattice gauge theory can be identified as a mathematical object in $K$-theory and that its associated spectral flow is equal to the index. In comparison to the standard lattice Dirac operator index,…

High Energy Physics - Theory · Physics 2025-07-08 Shoto Aoki , Hidenori Fukaya , Mikio Furuta , Shinichiroh Matsuo , Tetsuya Onogi , Satoshi Yamaguchi

We establish a formula for the spectral flow of a smooth family of twisted Dirac operators on a closed odd-dimensional Riemannian spin manifold, generalizing a result by Getzler. The spectral flow is expressed in terms of the $\hat{A}$-form…

Differential Geometry · Mathematics 2025-12-05 Christian Baer , Remo Ziemke

This paper is the third of the series concerning the localization of the index of Dirac-type operators. In our previous papers we gave a formulation of index of Dirac-type operators on open manifolds under some geometric setting, whose…

Differential Geometry · Mathematics 2014-07-18 Hajime Fujita , Mikio Furuta , Takahiko Yoshida

We develop a microlocal and derived-geometric framework for index theory and analytic torsion of nonlinear PDEs. By integrating Spencer hypercohomology, microlocal sheaf theory, and factorization algebras, we establish new connections…

Algebraic Geometry · Mathematics 2026-03-13 Jacob Kryczka , Vladimir Rubtsov , Artan Sheshmani , Shing-Tung Yau

The eta invariant appears regularly in index theorems but is known to be directly computable from the spectrum only in certain examples of locally symmetric spaces of compact type. In this work, we derive some general formulas useful for…

Differential Geometry · Mathematics 2024-05-17 Ruth Gornet , Ken Richardson

We derive a formula for the $\bar\mu$-invariant of a Seifert fibered homology sphere in terms of the eta-invariant of its Dirac operator. As a consequence, we obtain a vanishing result for the index of certain Dirac operators on plumbed…

Geometric Topology · Mathematics 2010-09-17 Daniel Ruberman , Nikolai Saveliev

We investigate the index of the Neuberger's Dirac operator in abelian gauge theories on finite lattices by numerically analyzing the spectrum of the hermitian Wilson-Dirac operator for a continuous family of gauge fields connecting…

High Energy Physics - Lattice · Physics 2009-10-31 T. Fujiwara

We introduce and study the index morphism for G-invariant leafwise G-transversally elliptic operators on smooth closed foliated manifolds which are endowed with leafwise actions of the compact group G. We prove the usual axioms of excision,…

K-Theory and Homology · Mathematics 2021-03-17 Alexandre Baldare , Moulay-Tahar Benameur

Let M be a compact manifold with a fixed spin structure \chi. The Atiyah-Singer index theorem implies that for any metric g on M the dimension of the kernel of the Dirac operator is bounded from below by a topological quantity depending…

Differential Geometry · Mathematics 2011-07-21 Bernd Ammann , Mattias Dahl , Emmanuel Humbert

We revisit a construction principle of Fredholm operators using Hilbert complexes of densely defined, closed linear operators and apply this to particular choices of differential operators. The resulting index is then computed with the help…

Functional Analysis · Mathematics 2020-06-19 Dirk Pauly , Marcus Waurick

This report investigates general relativity and the Yang-Mills theory in four-dimensional space-time using a common mathematical framework, the Chern-Weil theory for principal bundles. The whole theory is described owing to the fibre bundle…

General Relativity and Quantum Cosmology · Physics 2025-01-09 Yoshimasa Kurihara

We give an elementary solution of the index problem for elliptic operators associated with the shift operator along the trajectories of an isometric diffeomorphism of a closed smooth manifold. This solution is based on a reduction (which…

Analysis of PDEs · Mathematics 2011-12-26 A. Savin , E. Schrohe , B. Sternin

We review the concepts of the index of a Fredholm operator, the spectral flow of a curve of self-adjoint Fredholm operators, the Maslov index of a curve of Lagrangian subspaces in symplectic Hilbert space, and the eta invariant of operators…

Analysis of PDEs · Mathematics 2009-09-29 David Bleecker , Bernhelm Booss-Bavnbek

In our work we have reconsidered the old problem of diffusion at the boundary of ultrametric tree from a "number theoretic" point of view. Namely, we use the modular functions (in particular, the Dedekind eta-function) to construct the…

Statistical Mechanics · Physics 2009-11-10 Sergei Nechaev , Oleg Vasilyev