English
Related papers

Related papers: Indefinite Kasparov modules and pseudo-Riemannian …

200 papers

We investigate the notion of subsystem in the framework of spectral triple as a generalized notion of noncommutative submanifold. In the case of manifolds, we consider several conditions on Dirac operators which turn embedded submanifolds…

Mathematical Physics · Physics 2024-04-26 Paolo Bertozzini , Wanchalerm Sucpikarnon , Apimook Watcharangkool

We assign some kind of invariant manifolds to a given integrable PDE (its discrete or semi-discrete variant). First, we linearize the equation around its arbitrary solution $u$. Then we construct a differential (respectively, difference)…

Exactly Solvable and Integrable Systems · Physics 2018-04-25 Ismagil Habibullin , Aigul Khakimova

We describe the index pairing between an odd K-theory class and an odd unbounded Kasparov module by a pair of quasi-projections, supported on a submodule obtained from a finite spectral truncation. We achieve this by pairing the K-theory…

K-Theory and Homology · Mathematics 2026-04-01 Yuezhao Li , Bram Mesland

We construct Riemannian manifolds with singular continuous spectrum embedded in the absolutely continuous spectrum of the Laplacian. Our manifolds are asymptotically hyperbolic with sharp curvature bounds.

Spectral Theory · Mathematics 2021-11-03 Svetlana Jitomirskaya , Wencai Liu

A regular symmetric operator on a Hilbert module is self-adjoint whenever there exists a suitable approximate identity. We say an operator is 'locally bounded' if the composition of the operator with each element in the approximate identity…

Operator Algebras · Mathematics 2019-09-16 Koen van den Dungen

The Kauffman bracket skein module $K(M)$ of a 3-manifold $M$ is defined over formal power series in the variable $h$ by letting $A=e^{h/4}$. For a compact oriented surface $F$, it is shown that $K(F \times I)$ is a quantization of the…

q-alg · Mathematics 2008-02-03 Doug Bullock , Charles Frohman , Joanna Kania-Bartoszynska

In this study, we introduce indefinite sasakian statistical manifolds and lightlike hypersurfaces of an indefinite sasakian statistical manifold. Some relations among induced geometrical objects with respect to dual connections in a…

Differential Geometry · Mathematics 2021-09-21 Oğuzhan Bahadır

In his book Mickelsson notices that the infinite-dimensional Grassmannian manifold of Segal and Wilson admits a Spin^c structure and after this he naturally considers the problem of defining a Dirac operator on it. Mickelsson gives a…

Representation Theory · Mathematics 2010-07-27 Vesa Tahtinen

In a noncompact harmonic manifold $M$ we establish finite dimensionality of the eigenspaces $V_{\lambda}$ generated by radial eigenfunctions of the form $\cosh r + c$. As a consequence, for such harmonic manifolds, we give an isometric…

dg-ga · Mathematics 2008-02-03 K. Ramachandran , Akhil Ranjan

For the quantum Heisenberg manifolds, using the action of Heisenberg group we construct a family of spectral triples. It is shown that associated Kasparov module is same for all these spectral triples. Then we show that element is…

Operator Algebras · Mathematics 2007-05-23 Partha Sarathi Chakraborty , Kalyan B. Sinha

In this paper, isometric embedding results of Greene, Gromov and Rokhlin are extended to what are called "indefinite metric polyhedra". Two definitions for an indefinite metric polyhedron are given, an intuitive definition and a more useful…

Metric Geometry · Mathematics 2015-08-06 Barry Minemyer

We construct compact hyperbolic 3-manifolds with totally geodesic boundary, such that the closed 3-pseudomanifolds obtained by coning off the boundary components are negatively curved and contain locally convex subspaces whose fundamental…

Geometric Topology · Mathematics 2026-02-11 Jason Manning , Lorenzo Ruffoni

In this work, we use tools from non-standard analysis to introduce infinite-dimensional quantum systems and quantum fields within the framework of Categorical Quantum Mechanics. We define a dagger compact category *Hilb suitable for the…

Quantum Physics · Physics 2018-03-05 Stefano Gogioso , Fabrizio Genovese

We construct discrete versions of $\kappa$-Minkowski space related to a certain compactness of the time coordinate. We show that these models fit into the framework of noncommutative geometry in the sense of spectral triples. The dynamical…

High Energy Physics - Theory · Physics 2011-11-28 Bruno Iochum , Thierry Masson , Thomas Schücker , Andrzej Sitarz

Quantum mechanics, in principle, allows for processes with indefinite causal order. However, most of these causal anomalies have not yet been detected experimentally. We show that every such process can be simulated experimentally by means…

Quantum Physics · Physics 2018-04-04 Simon Milz , Felix A. Pollock , Thao P. Le , Giulio Chiribella , Kavan Modi

This paper begins the study of infinite-dimensional modules defined on bicomplex numbers. It generalizes a number of results obtained with finite-dimensional bicomplex modules. The central concept introduced is the one of a bicomplex…

Functional Analysis · Mathematics 2011-08-10 Raphael Gervais Lavoie , Louis Marchildon , Dominic Rochon

We factorize the Dirac operator on the Connes-Landi 4-sphere in unbounded KK-theory. We show that a family of Dirac operators along the orbits of the torus action defines an unbounded Kasparov module, while the Dirac operator on the…

Operator Algebras · Mathematics 2019-08-28 Jens Kaad , Walter D. van Suijlekom

The authors exhibit pairs of infinite-volume, hyperbolic three-manifolds that have the same scattering poles and conformally equivalent boundaries, but which are not isometric. The examples are constructed using Schottky groups and the…

Differential Geometry · Mathematics 2007-05-23 Robert Brooks , Ruth Gornet , Peter Perry

Various characterizations of unbounded closed densely defined operators commuting with the spectral measures of their moduli are established.In particular, Kaufman's definition of an unbounded quasinormal operator is shown to coincide with…

Functional Analysis · Mathematics 2016-11-25 Zenon Jan Jablonski , Il Bong Jung , Jan Stochel

We continue our study of ends non-compact manifolds. The over-arching aim is to provide an appropriate generalization of Siebenmann's famous collaring theorem that applies to manifolds having non-stable fundamental group systems at…

Geometric Topology · Mathematics 2009-03-03 Craig R Guilbault , Frederick C Tinsley