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We discuss the problems of incompleteness and inexpressibility. We introduce almost self-referential formulas, use them to extend set theory, and relate their expressive power to that of infinitary logic. We discuss the nature of proper…

Logic · Mathematics 2016-12-20 Dmytro Taranovsky

We associate canonically a cyclic module to any Hopf algebra endowed with a modular pair, consisting of a group-like element and a character, in involution. This provides the key construct allowing to extend cyclic cohomology to Hopf…

Quantum Algebra · Mathematics 2007-05-23 Alain Connes , Henri Moscovici

Motivated by the classical correspondence between short exact sequences and splitting properties in module theory, this paper examines the projective and injective analogues within the category of Lie algebras. We first show that no Lie…

Rings and Algebras · Mathematics 2025-11-18 Vu A. Le , Hoa Q. Duong , Tuan A. Nguyen

For a projective variety $X$ defined over a non-Archimedean complete non-trivially valued field $k$, and a semipositive metrized line bundle $(L, \phi)$ over it, we establish a metric extension result for sections of $L^{\otimes n}$ from a…

Algebraic Geometry · Mathematics 2019-04-09 Yanbo Fang

We provide a comparison test for meromorphic extensions, i.e., if two series are ``close enough" then the existence of a meromorphic extension of one to the entire complex plane ensures a similar extension for the other. We use this result…

Complex Variables · Mathematics 2026-05-04 Adi Glücksam , Yuzhou Joey Zou

The main result of the paper is a flat extension theorem for positive linear functionals on *-algebras. The theorem is applied to truncated moment problems on cylinder sets, on matrices of polynomials and on enveloping algebras of Lie…

Algebraic Geometry · Mathematics 2014-06-20 Bernard Mourrain , Konrad Schmüdgen

In 1991, Yannakakis (J. Comput. System Sci., 1991) proved that no symmetric extended formulation for the matching polytope of the complete graph K_n with n nodes has a number of variables and constraints that is bounded subexponentially in…

Combinatorics · Mathematics 2015-05-14 Volker Kaibel , Kanstantsin Pashkovich , Dirk Oliver Theis

The Expansion property considered by researchers in Social Choice is shown to correspond to a logical property of nonmonotonic consequence relations that is the {\em pure}, i.e., not involving connectives, version of a previously known weak…

Artificial Intelligence · Computer Science 2007-05-23 Daniel Lehmann

We consider the problem of extending an acyclic binary relation that is invariant under a given family of transformations into an invariant preference. We show that when a family of transformations is commutative, every acyclic invariant…

Theoretical Economics · Economics 2023-03-09 Peter Caradonna , Christopher P. Chambers

We give a criterium of holomorphy for some type formal power series. This gives a stronger form of a Rothstein's type extension theorem for a particular ring of holomorphic functions.

Dynamical Systems · Mathematics 2007-05-23 Ricardo Perez-Marco

We show that there is a restriction, or modification of the finite-variable fragments of First Order Logic in which a weak form of Craig's Interpolation Theorem holds, but a strong form of this theorem does not hold. Translating these…

Logic · Mathematics 2007-05-23 Gabor Sagi , Saharon Shelah

The zero-error capacity of a classical channel is a parameter of its confusability graph, and is equal to the minimum of the values of graph parameters that are additive under the disjoint union, multiplicative under the strong product,…

Information Theory · Computer Science 2022-07-22 Péter Vrana

This paper deals with extension of analytic covers. We prove topological extension theorems for analytic covers. The main result is an extension theorem which only uses the extension of the ramification divisor. We give also a Thullen-type…

Complex Variables · Mathematics 2016-04-28 Landry Lavoine

We introduce an object that has obvious similarity to the classical one - the algebra of supersymmetric polynomials. Despite the similarity, the known structure theorems on supersymmetric polynomials do not help in the study of the new…

Commutative Algebra · Mathematics 2024-07-29 Grigory Chelnokov , Maxim Turevskii

We define a loop to be quantum nullhomotopic if and only if it admits a nonempty quantum set of extensions to the unit disk. We show that the canonical loop in the unit circle is not quantum nullhomotopic, but that every loop in the real…

Operator Algebras · Mathematics 2018-11-29 Andre Kornell

In this paper we prove certain properties of cellular and acyclic classes of chain complexes of modules over a commutative Noetherian ring. In particular we show that if X is finite and belongs to some cellular class C then \Sigma^n H_X…

Algebraic Topology · Mathematics 2008-03-19 Jonas Kiessling

We show that symmetry in the vanishing of cohomology holds for graded modules over quantum complete intersections. Moreover, symmetry holds for all modules if the algebra is symmetric.

K-Theory and Homology · Mathematics 2008-11-27 Petter Andreas Bergh

Given a pair of nilpotent Lie algebras $A$ and $B$, an extension $0\xrightarrow{} A\xrightarrow{} L\xrightarrow{} B\xrightarrow{} 0$ is not necessarily nilpotent. However, if $L_1$ and $L_2$ are extensions which correspond to lifts of a map…

Rings and Algebras · Mathematics 2021-05-31 Erik Mainellis

The generalized Hamming weights (GHWs) of linear codes are fundamental parameters, the knowledge of which is of great interest in many applications. However, to determine the GHWs of linear codes is difficult in general. In this paper, we…

Information Theory · Computer Science 2015-04-07 Maosheng Xiong , Shuxing Li , Gennian Ge

In this paper we will establish a structure theorem concerning the extension of analytic objects associated to germs of dimension one foliations on surfaces, through one-dimensional barriers. As an application, an extension theorem for…

Complex Variables · Mathematics 2010-10-08 César Camacho , Bruno Scárdua