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Related papers: Controlled K-theory I: Basic theory

200 papers

This paper presents a survey on quantum control theory and applications from a control systems perspective. Some of the basic concepts and main developments (including open-loop control and closed-loop control) in quantum control theory are…

Quantum Physics · Physics 2011-01-12 Daoyi Dong , Ian R Petersen

We prove an exact control theorem, in the sense of Hida theory, for the ordinary part of the middle degree \'etale cohomology of certain Hilbert modular varieties, after localizing at a suitable maximal ideal of the Hecke algebra. Our…

Number Theory · Mathematics 2025-04-30 Arshay Sheth

We determine the $K$-theory of the $C^{*}$-algebra $C(SU_{-1}(2))$ and describe its spectrum. Moreover, we exhibit a continuous $C^{*}$-bundle over $[-1,0)$ whose fibre at $q$ is isomorphic to $C(SU_{q}(2))$.

Operator Algebras · Mathematics 2015-03-06 Selcuk Barlak

In this article we prove that the $KH$-asembly map, as defined by Bartels and L{\"u}ck, can be described in terms of the algebraic $KK$-theory of Cortinas and Thom. The $KK$-theory description of the $KH$-assembly map is similar to that of…

K-Theory and Homology · Mathematics 2009-01-14 Paul D. Mitchener

Let $S$ be subsemigroup with nonempty interior of a complex simple Lie group $G$. It is proved that $S=G$ if $S$ contains a subgroup $G(\alpha) \approx \mathrm{Sl}(2,\mathbb{C}) $ generated by the $\exp \mathfrak{g}_{\pm \alpha}$, where…

Optimization and Control · Mathematics 2011-04-28 Ariane Luzia dos Santos , Luiz A. B. San Martin

Generalized differential cohomology theories, in particular differential K-theory (often called "smooth K-theory"), are becoming an important tool in differential geometry and in mathematical physics. In this survey, we describe the…

K-Theory and Homology · Mathematics 2012-02-13 Ulrich Bunke , Thomas Schick

We investigate the relative assembly map from the family of finite subgroups to the family of virtually cyclic subgroups for the algebraic $K$-theory of twisted group rings of a group G with coefficients in a regular ring R or, more…

K-Theory and Homology · Mathematics 2024-08-02 Wolfgang Lueck

We consider twisted equivariant K--theory for actions of a compact Lie group $G$ on a space $X$ where all the isotropy subgroups are connected and of maximal rank. We show that the associated rational spectral sequence \`a la Segal has a…

Algebraic Topology · Mathematics 2019-10-01 Alejandro Adem , José Cantarero , José Manuel Gómez

Let $F$ be a finite group. We consider the lamplighter group $L=F\wr\mathbb{Z}$ over $F$. We prove that $L$ has a classifying space for proper actions $\underline{E} L$ which is a complex of dimension two. We use this to give an explicit…

Operator Algebras · Mathematics 2017-09-06 Ramón Flores , Sanaz Pooya , Alain Valette

This paper addresses the fundamental question of determining the minimum number of distinct control laws required for global controllability of nonlinear systems that exhibit singularities in their feedback linearising controllers. We…

Computational Engineering, Finance, and Science · Computer Science 2026-03-20 Nikolaos D. Tantaroudas

For a smooth manifold X of dimension <d we construct a homomorphism from the algebraic K-theory group in degree d of the algebra of smooth functions on X to the degree -d-1 topological K-theory of X with coefficients in C/Z. This map…

K-Theory and Homology · Mathematics 2014-12-09 Ulrich Bunke

We study the K-stability of a polarised variety with non-reductive automorphism group. We associate a canonical filtration of the co-ordinate ring to each variety of this kind, which destabilises the variety in several examples which we…

Algebraic Geometry · Mathematics 2016-08-15 Giulio Codogni , Ruadhaí Dervan

To each algebra over the complex numbers we associate a sequence of abelian groups in a contravariant functorial way. In degree (m-1) we have the m-summable Fredholm modules over the algebra modulo stable m-summable perturbations. These new…

K-Theory and Homology · Mathematics 2010-02-02 Jens Kaad

We generalize the result of Brandenbursky and Marcinkowski for the bounded cohomology of transformation groups to infinite volume case. To state the result, we introduce the notion of norm controlled cohomology as a generalization of…

Geometric Topology · Mathematics 2023-02-16 Mitsuaki Kimura

We develop a theory of motivic spectra in a broad generality; in particular $\mathbb{A}^1$-homotopy invariance is not assumed. As an application, we prove that $K$-theory of schemes is a universal Zariski sheaf of spectra which is equipped…

Algebraic Geometry · Mathematics 2025-04-18 Toni Annala , Ryomei Iwasa

Equivalence classes of gapped Hamiltonians compatible with given symmetry constraints, such as those underlying topological insulators, can be defined in many ways. For the non-chiral classes modelled by vector bundles over Brillouin tori,…

Mathematical Physics · Physics 2015-10-13 Guo Chuan Thiang

Consider complex semisimple Lie algebras of a given dimension specified by their structure constants. We describe a finite collection of rational functions in the structure constants that form a complete set of invariants: two sets of…

Rings and Algebras · Mathematics 2007-05-23 Vijay Kodiyalam , K. N. Raghavan

Recent advances in computational techniques for $K$-theory allow us to describe the $K$-theory of toric varieties in terms of the $K$-theory of fields and simple cohomological data.

K-Theory and Homology · Mathematics 2011-08-03 Guillermo Cortiñas , Christian Haesemeyer , Mark E. Walker , Charles Weibel

Analytical tools to $K$-theory; namely, self-stabilization of rapidly decreasing matrices, linearization of cyclic loops, and the contractibility of the pointed stable Toeplitz algebra are discussed in terms of concrete formulas. Adaptation…

K-Theory and Homology · Mathematics 2013-05-31 Gyula Lakos

The Isomorphism Conjecture is a conceptional approach towards a calculation of the algebraic K-theory of a group ring RG, where G is an infinite group. In this paper we prove the conjecture in dimensions n<2 for fundamental groups of closed…

Algebraic Topology · Mathematics 2007-05-23 Arthur Bartels , Tom Farrell , Lowell Jones , Holger Reich