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Related papers: Nonexistence of k-bounded sobrification

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For an associative ring $R$ with identity, we study the absence of $k$-torsion in NK_1GQ(R); Bass nil-groups for the general quadratic or Bak's unitary groups. By using a graded version of Quillen--Suslin theory we deduce an analog for the…

K-Theory and Homology · Mathematics 2021-01-19 Rabeya Basu , Kuntal Chakraborty

We introduce certain $C^*$-algebras and $k$-graphs associated to $k$ finite dimensional unitary representations $\rho_1,...,\rho_k$ of a compact group $G$. We define a higher rank Doplicher-Roberts algebra $\mathcal{O}_{\rho_1,...,\rho_k}$,…

Operator Algebras · Mathematics 2020-06-26 Valentin Deaconu

We give a description of the value of a finitary localizing invariant, such as algebraic $K$-theory, on the category of sheaves on a locally coherent space $X$. This in particular includes all spaces that arise as spectra of commutative…

K-Theory and Homology · Mathematics 2025-10-16 Georg Lehner

In this paper we show that the $K_0$ groups of noncommutative $\mathbb{R}^{2n}$ are $\mathbb{Z}$ for $\forall n\in\mathbb{N}^*$ and make an approach to the calculation of the smooth case, which will bring many new sequence problems relating…

Rings and Algebras · Mathematics 2022-11-01 Ren Guan

We prove that a separable Banach space $E$ does not contain a copy of the space $\co$ of null-sequences if and only if for every doubly power-bounded operator $T$ on $E$ and for every vector $x\in E$ the relative compactness of the sets…

Functional Analysis · Mathematics 2013-01-29 Bálint Farkas

In this paper, we introduce a notion of strongly quasi-local algebras. They are defined for each discrete metric space with bounded geometry, and sit between the Roe algebra and the quasi-local algebra. We show that strongly quasi-local…

Operator Algebras · Mathematics 2021-08-03 Hengda Bao , Xiaoman Chen , Jiawen Zhang

Recursive domain equations have natural solutions. In particular there are domains defined by strictly positive induction. The class of countably based domains gives a computability theory for possibly non-countably based topological…

Logic in Computer Science · Computer Science 2015-07-01 Petter Kristian Køber

We give an explicit description of the set of all factorization structures, or twisting maps, existing between the algebras k^2 and k^2, and classify the resulting algebras up to isomorphism. In the process we relate several different…

Rings and Algebras · Mathematics 2016-08-16 Javier López Peña , Gabriel Navarro

In our previous works we have classified real non-singular cubic hypersurfaces in the 5-dimensional projective space up to equivalence that includes both real projective transformations and continuous variations of coefficients preserving…

Algebraic Geometry · Mathematics 2020-03-10 Sergey Finashin , Viatcheslav Kharlamov

We consider two families of finite-dimensional simple Lie superalgebras of Cartan type, denoted by HO and KO, over an algebraically closed field of characteristic p>3. Using the weight space decompositions and the principal gradings we…

Rings and Algebras · Mathematics 2018-07-25 Jixia Yuan , Wende Liu , Wei Bai

We describe Baily-Borel, toroidal, and geometric -- using the KSBA stable pairs -- compactifications of some moduli spaces of K3 surfaces with a nonsymplectic automorphism of order $3$ and $4$ for which the fixed locus of the automorphism…

Algebraic Geometry · Mathematics 2025-02-12 Valery Alexeev , Anand Deopurkar , Changho Han

Assuming Lang's conjecture, we prove that for a fixed prime $p$, number field $K$, and positive integer $g$, there is an integer $r$ such that no principally polarized abelian variety $A/K$ of dimension $g$ has full level $p^r$ structure.…

Algebraic Geometry · Mathematics 2016-11-15 Dan Abramovich , Anthony Várilly-Alvarado

We prove that the category of McKinsey-Tarski algebras is not equivalent to a variety of algebras, thus answering a question of Peter Jipsen in the negative. More generally, we show that various categories of BAOs (boolean algebras with an…

Logic · Mathematics 2026-03-17 Marco Abbadini , Guram Bezhanishvili , Luca Carai

It has long been known that a key ingredient for a sheaf representation of a universal algebra A consists in a distributive lattice of commuting congruences on A. The sheaf representations of universal algebras (over stably compact spaces)…

Category Theory · Mathematics 2023-05-16 Marco Abbadini , Luca Reggio

Quantization, at least in some formulations, involves replacing some algebra of observables by a (more non-commutative) deformed algebra. In view of the fundamental role played by K-theory in non-commutative geometry and topology, it is of…

q-alg · Mathematics 2013-02-28 Jonathan Rosenberg

In the first part of this paper, we prove the existence of torsion free covers in the category of representations of quivers, $(Q,R-Mod)$, for a wide class of quivers included in the class of the so-called source injective representation…

Category Theory · Mathematics 2010-09-02 Sergio Estrada , Salahattin Özdemir

We prove each embedded, constant mean curvature (CMC) surface in Euclidean space with genus zero and finitely many coplanar ends is nondegenerate: there is no nontrivial square-integrable solution to the Jacobi equation, the linearization…

Differential Geometry · Mathematics 2010-06-14 Karsten Grosse-Brauckmann , Nicholas J. Korevaar , Robert B. Kusner , Jesse Ratzkin , John M. Sullivan

We study M-separability as well as some other combinatorial versions of separability. In particular, we show that the set-theoretic hypothesis b=d implies that the class of selectively separable spaces is not closed under finite products,…

General Topology · Mathematics 2010-10-13 Dušan Repovš , Lyubomyr Zdomskyy

The existence of a strict deformation quantization of $X_k=S(M_k({\mathbb{C}}))$, the state space of the $k\times k$ matrices $M_k({\mathbb{C}})$ which is canonically a compact Poisson manifold (with stratified boundary) has recently been…

Mathematical Physics · Physics 2020-10-13 Valter Moretti , Christiaan J. F van de Ven

We prove a non-linear version of a theorem of Grayson which is an analogue of the Fundamental Theorem of Algebraic $K$-theory and identify the $K$-theory of the endomorphism category over a space $X$ in terms of reduced $K$-theory of a…

K-Theory and Homology · Mathematics 2015-11-30 Filipp Levikov