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Related papers: A new kind of index theorem

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We generalize Roe's Index Theorem for operators of Dirac type on open manifolds to elliptic pseudodifferential operators. To this end we introduce a class of pseudodifferential operators on manifolds of bounded geometry which is more…

Differential Geometry · Mathematics 2014-10-30 Alexander Engel

For three classes of elliptic pseudodifferential operators on a compact manifold with boundary which have `geometric K-theory', namely the `transmission algebra' introduced by Boutet de Monvel, the `zero algebra' introduced by Mazzeo and…

Differential Geometry · Mathematics 2010-12-30 Pierre Albin , Richard Melrose

In the setting of several commuting operators on a Hilbert space one defines the notions of invertibility and Fredholmness in terms of the associated Koszul complex. The index problem then consists of computing the Euler characteristic of…

K-Theory and Homology · Mathematics 2012-10-24 Jens Kaad , Ryszard Nest

Results of Haagerup and Schultz (2009) about existence of invariant subspaces that decompose the Brown measure are extended to a large class of unbounded operators affiliated to a tracial von Neumann algebra. These subspaces are used to…

Operator Algebras · Mathematics 2015-09-14 Ken Dykema , Fedor Sukochev , Dmitriy Zanin

We present other examples illustrating the operator-theoretic approach to invariant integrals on quantum homogeneous spaces developed by Kuersten and the second author. The quantum spaces are chosen such that their coordinate algebras do…

Quantum Algebra · Mathematics 2009-04-07 Osvaldo Osuna Castro , Elmar Wagner

Our main result is a theorem saying that a bounded operator $A$ on a Hilbert space belongs to a certain set associated with its self-commutator $[A^*,A]$, provided that $A-zI$ can be approximated by invertible operators for all complex…

Operator Algebras · Mathematics 2009-10-25 N. Filonov , Y. Safarov

Let $A$ be a $m\times m$ complex matrix with zero trace. Then there are $m\times m$ matrices $B$ and $C$ such that $A=[B,C]$ and $\|B\|\|C\|_2\le (\log m+O(1))^{1/2}\|A\|_2$ where $\|D\|$ is the norm of $D$ as an operator on $\ell_2^m$ and…

Functional Analysis · Mathematics 2017-05-17 Omer Angel , Gideon Schechtman

Let X be a closed connected contact manifold. On X there is a naturally arising class of hypoelliptic (but not elliptic) operators which are Fredholm. In this paper we solve the index problem for this class of operators. The solution is…

Operator Algebras · Mathematics 2012-12-07 Paul F. Baum , Erik van Erp

This paper is about the orbifold theory for vertex operator superalgebras. Given a vertex operator superalgebra V and a finite automorphism group G of V, we show that the trace functions associated to the twisted sectors are holomorphic in…

Quantum Algebra · Mathematics 2009-11-10 Chongying Dong , Zhongping Zhao

Linear spaces with an Euclidean metric are ubiquitous in mathematics, arising both from quadratic forms and inner products. Operators on such spaces also occur naturally. In recent years, the study of multivariate operator theory has made…

Functional Analysis · Mathematics 2019-01-15 Gadadhar Misra

In previous work, we gave a local formula for the index of Heisenberg elliptic operators on contact manifolds. We constructed a cocycle in periodic cyclic cohomology which, when paired with the Connes-Chern character of the principal…

Functional Analysis · Mathematics 2025-04-18 Alexander Gorokhovsky , Erik van Erp

We prove an index theorem for inhomogeneous differential operators satisfying the Rockland condition (hence hypoelliptic). This theorem extends an index theorem for contact manifolds by Van-Erp.

K-Theory and Homology · Mathematics 2020-01-03 Omar Mohsen

We define Schatten classes of adjointable operators on Hilbert modules over abelian $C^*$-algebras. Many key features carry over from the Hilbert space case. In particular, the Schatten classes form two-sided ideals of compact operators and…

Operator Algebras · Mathematics 2020-10-16 Abel B. Stern , Walter D. van Suijlekom

The goal of this paper is to construct a calculus whose higher indices are naturally elements in the twisted K-theory groups for Lie groupoids. Given a Lie groupoid $G$ and a $PU(H)$-valued groupoid cocycle, we construct an algebra of…

Operator Algebras · Mathematics 2018-01-15 Paulo Carrillo Rouse

In this note we prove that the set of all uniformly continuous units on a product system over a C* algebra B can be endowed with the structure of left right B - B Hilbert module after identifying similar units by the suitable equivalence…

Operator Algebras · Mathematics 2015-12-15 Dragoljub J. Kečkić , Biljana Vujošević

In this paper we examine an inverse problem in the modular theory of von Neumann algebras in the case of finite factors. First we give a characterization of cyclic and separating vectors for finite factors in terms of operators associated…

Operator Algebras · Mathematics 2007-05-23 Stefan Boller

The notion of a subtractive category, recently introduced by the author, is a ``categorical version'' of the notion of a (pointed) subtractive variety of universal algebras, due to A. Ursini. We show that a subtractive variety $\C$, whose…

Category Theory · Mathematics 2007-05-23 Zurab Janelidze

We develop by example a type of index theory for non-Fredholm operators. A general framework using cyclic homology for this notion of index was introduced in a separate article [CaKa13] where it may be seen to generalise earlier ideas of…

Functional Analysis · Mathematics 2014-05-20 Alan Carey , Harald Grosse , Jens Kaad

The class of operator-valued functions which are homogeneous of degree one, holomorphic in the open right polyhalfplane, have positive semidefinite real parts there and take selfadjoint operator values at real points, and its subclass…

Functional Analysis · Mathematics 2016-09-07 Dmitry S. Kalyuzhnyi-Verbovetzkii

We first generalize the logarithmic tensor category theory of Huang-Lepowsky-Zhang to the more general case that the module category for a vertex operator algebra $V$ (more generally a M\"{o}bius vertex algebra) might not be closed under…

Quantum Algebra · Mathematics 2025-09-26 Yi-Zhi Huang