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Let $M$ be a compact manifold. and $D$ a Dirac type differential operator on $M$. Let $A$ be a $C^*$-algebra. Given a bundle $W$ of $A$-modules over $M$ (with connection), the operator $D$ can be twisted with this bundle. One can then use a…

Geometric Topology · Mathematics 2007-05-23 Thomas Schick

First we make a brief review of coherent states and prove that the resolution of unity can be obtained by the 1-st Chern character of some bundle. Next we define a Grassmann manifold for a set of coherent states and construct the pull-back…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kazuyuki Fujii

The "superconformal index" is a character-valued invariant attached by theoretical physics to unitary representations of Lie superalgebras, such as $\mathfrak{su}(2,2\vert n)$, that govern certain quantum field theories. The index can be…

Representation Theory · Mathematics 2025-04-15 Steffen Schmidt , Johannes Walcher

We introduce and analyse a new type of quantum 2-spheres. Then we apply index theory for noncommutative line bundles over these spheres to conclude that quantum lens spaces are non-crossed-product examples of principal extensions of…

K-Theory and Homology · Mathematics 2007-05-23 Piotr M. Hajac , Rainer Matthes , Wojciech Szymanski

The set of the first Hilbert coefficients of parameter ideals relative to a module--its Chern coefficients--over a local Noetherian ring codes for considerable information about its structure--noteworthy properties such as that of…

Commutative Algebra · Mathematics 2014-04-03 Laura Ghezzi , Shiro Goto , Jooyoun Hong , Kazuho Ozeki , Tran Phuong , Wolmer Vasconcelos

We develop a uniform semiclassical trace formula for the density of states of a three-dimensional isotropic harmonic oscillator (HO), perturbed by a term $\propto r^4$. This term breaks the U(3) symmetry of the HO, resulting in a spherical…

Exactly Solvable and Integrable Systems · Physics 2016-08-16 M. Brack , M. Ögren , Y. Yu , S. M. Reimann

We define a map from the skein module of a cusped hyperbolic 3-manifold to the ring of Laurent series in one variable with integer coefficients that satisfies two properties: its evaluation at peripheral curves coincides with the…

Geometric Topology · Mathematics 2024-06-10 Stavros Garoufalidis , Tao Yu

We prove a Tauberian theorem for singular values of noncommuting operators which allows us to prove exact asymptotic formulas in noncommutative geometry at a high degree of generality. We explain how, via the Birman--Schwinger principle,…

Operator Algebras · Mathematics 2021-06-07 Edward McDonald , Fedor Sukochev , Dmitriy Zanin

In this paper we prove a version of Connes' trace theorem for noncommutative tori of any dimension~$n\geq 2$. This allows us to recover and improve earlier versions of this result in dimension $n=2$ and $n=4$ by Fathizadeh-Khalkhali. We…

Operator Algebras · Mathematics 2020-05-20 Raphael Ponge

This paper introduces a boundary integral equation for time-harmonic electromagnetic scattering by composite dielectric objects. The formulation extends the classical M\"uller equation to composite structures through the global multi-trace…

Numerical Analysis · Mathematics 2026-01-21 Van Chien Le , Kristof Cools

We present a connection between twisted spectral triples and pseudo-Riemannian spectral triples, rooted in the fundamental interplay between twists and Krein products. A concept of morphism of spectral triples is introduced, transforming…

Mathematical Physics · Physics 2026-03-03 Gaston Nieuviarts

Let \( m, n \in \mathbb{N}_0 \), and let \( X \) be a closed subset of \( \mathbb{T}^{\binom{m+n}{2}} \). We define \( C^{m,n}_X \) to be the universal \( C^* \)-algebra among those generated by \( m \) unitaries and \( n \) isometries…

Operator Algebras · Mathematics 2025-06-23 Shreema Subhash Bhatt , Surajit Biswas , Bipul Saurabh

Twisted complex $K$-theory can be defined for a space $X$ equipped with a bundle of complex projective spaces, or, equivalently, with a bundle of C$^*$-algebras. Up to equivalence, the twisting corresponds to an element of $H^3(X;\Z)$. We…

K-Theory and Homology · Mathematics 2007-05-23 Michael Atiyah , Graeme Segal

We conjecture, and show in a plethora of examples, that the sphere partition function of 3d $\mathcal{N}=4$ Chern-Simons-matter theories equals a sum of twisted traces on tensor products of Verma modules over the quantization of the moduli…

High Energy Physics - Theory · Physics 2026-05-21 Leonardo Santilli

We introduce a twisted version of $K$-theory with coefficients in a $C^*$-algebra $A$, where the twist is given by a new kind of gerbe, which we call Morita bundle gerbe. We use the description of twisted $K$-theory in the torsion case by…

K-Theory and Homology · Mathematics 2011-03-22 Ulrich Pennig

The local index formula of Connes--Moscovici for the isospectral noncommutative geometry recently constructed on quantum SU(2) is discussed. The cosphere bundle and the dimension spectrum as well as the local cyclic cocycles yielding the…

Quantum Algebra · Mathematics 2007-05-23 Ludwik Dabrowski

The classical Frobenius-Schur indicators for finite groups are character sums defined for any representation and any integer m greater or equal to 2. In the familiar case m=2, the Frobenius-Schur indicator partitions the irreducible…

Quantum Algebra · Mathematics 2013-09-25 Daniel S. Sage , Maria D. Vega

Trace formulas appear in many forms in noncommutative geometry (NCG). In the first part of this thesis, we obtain results for asymptotic expansions of trace formulas like heat trace expansions by adapting the theory of Multiple Operator…

Operator Algebras · Mathematics 2025-06-30 Eva-Maria Hekkelman

In this paper, we study the properties of Connes spectral distances between quantum states under unitary transformations. We mainly focus on spectral triples with matrix algebras acting on finite dimensional Hilbert spaces via some linear…

Mathematical Physics · Physics 2026-05-14 Ji-Hong Wang , Bing-Sheng Lin , Zhi-Kang You

Chern insulators, which are the lattice analogs of the quantum Hall states, can potentially manifest high-temperature topological orders at zero magnetic field to enable next-generation topological quantum devices. To date, integer Chern…