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We introduce a framework allowing for key aspects of deformation/rigidity theory to be used in the study of continuous model theory of II$_1$ factors. Using this framework, we solve several well-known open problems in the area. For example,…

Operator Algebras · Mathematics 2026-05-19 Jesse Peterson

We explore the possibilities for elementary embeddings $j : M \to N$, where $M$ and $N$ are models of ZFC with the same ordinals, $M \subseteq N$, and $N$ has access to large pieces of $j$. We construct commuting systems of such maps…

Logic · Mathematics 2023-03-27 Monroe Eskew , Sy-David Friedman

The addition of a topologically massive term to an admittedly non-unitary three-dimensional massive model, be it an electromagnetic system or a gravitational one, does not cure its non-unitarity. What about the enlargement of avowedly…

High Energy Physics - Theory · Physics 2009-11-11 Antonio Accioly , Marco Dias

We develop a theory of universal central extensions of Hom-Lie algebras. Classical results of universal central extensions of Lie algebras cannot be completely extended to Hom-Lie algebras setting, because of the composition of two central…

Rings and Algebras · Mathematics 2012-09-27 J. M. Casas , M. A. Insua , N. Pacheco

We appended an errata to the original submission. The purpose of this errata is to point out two errors in [2] and give a weakened version of those statements made.

Probability · Mathematics 2024-07-02 Erhan Bayraktar , Gaoyue Guo

There exist two different languages, the ^sl(2) and N=2 ones, to describe similar structures; a dictionary is given translating the key representation-theoretic terms related to the two algebras. The main tool to describe the structure of…

High Energy Physics - Theory · Physics 2009-10-30 A M Semikhatov

Let $\A$ be an abelian category having enough projective objects and enough injective objects. We prove that if $\A$ admits an additive generating object, then the extension dimension and the weak resolution dimension of $\A$ are identical,…

Representation Theory · Mathematics 2019-02-26 Junling Zheng , Xin Ma , Zhaoyong Huang

Under CH we prove that for any tall ideal $\cal I$ on $\omega$ and for any ordinal $\gamma \leq \omega_1$ there is an ${\cal I}$-ultrafilter (in the sense of Baumgartner), which belongs to the class ${\cal P}_{\gamma}$ of P-hierarchy of…

Logic · Mathematics 2011-11-22 Michał Machura , Andrzej Starosolski

We study some non-semisimple representations of affine Temperley--Lieb algebras and related cellular algebras. In particular, we classify extensions between simple standard modules. Moreover, we construct a completion which is an infinite…

Representation Theory · Mathematics 2007-05-23 K. Erdmann , R. M. Green

We present two different types of models where, for certain singular cardinals lambda of uncountable cofinality, lambda -> (lambda, omega+1)^2, although lambda is not a strong limit cardinal. We announce, here, and will present in a…

Logic · Mathematics 2016-09-07 Saharon Shelah , Lee Stanley

We describe the immediate extensions of a one dimensional valuation ring $V$ which could be embedded in some separation of a ultrapower of $V$ with respect to a certain ultrafilter. For such extensions holds a kind of Artin's approximation.

Commutative Algebra · Mathematics 2020-11-17 Dorin Popescu

Let $\mathbb{Q}(\alpha)$ and $\mathbb{Q}(\beta)$ be linearly disjoint number fields and let $\mathbb{Q}(\theta)$ be their compositum. We prove that the first-degree prime ideals of $\mathbb{Z}[\theta]$ may almost always be constructed in…

Number Theory · Mathematics 2025-04-16 Giordano Santilli , Daniele Taufer

Spatial models of preference, in the form of vector embeddings, are learned by many deep learning and multiagent systems, including recommender systems. Often these models are assumed to approximate a Euclidean structure, where an…

Artificial Intelligence · Computer Science 2023-05-16 Luke Thorburn , Maria Polukarov , Carmine Ventre

We extend the notion of exact completion on a weakly lex category to elementary doctrines. We show how any such doctrine admits an elementary quotient completion, which freely adds effective quotients and extensional equality. We note that…

Category Theory · Mathematics 2012-06-04 Maria Emilia Maietti , Giuseppe Rosolini

Let $(M,\scott X) \models \ACA$ be such that $P_\scott X$, the collection of all unbounded sets in $\scott X$, admits a definable complete ultrafilter and let $T$ be a theory extending first order arithmetic coded in $\scott X$ such that…

Logic · Mathematics 2010-03-16 Fredrik Engström

Let n be finite >2. We show that any class between S\Nr_n\CA_{n+3} and RCA_n is not atom canonical, and any class containing the class of completely representable algebras and contained in S_c\Nr_n\CA_{n+3} is not elementary. We show that…

Logic · Mathematics 2014-01-07 Tarek Sayed Ahmed

In this Letter, two counterexamples show that the superadditivity inequality of relative entropy is not true even for the full-ranked quantum states. Thus, an inequality of quantum channels and complementary channels is not also true.…

Quantum Physics · Physics 2013-06-10 Lin Zhang , Junde Wu , Shao-Ming Fei

In this work we provide alternative formulations of the concepts of lambda theory and extensional theory without introducing the notion of substitution and the sets of all, free and bound variables occurring in a term. We also clarify the…

Logic in Computer Science · Computer Science 2019-03-21 Michele Basaldella

We generalize to the relations $(\lambda, \mu) \stackrel{\kappa}{\Rightarrow} (\lambda', \mu')$ and $\alm (\lambda, \mu) \stackrel{\kappa}{\Rightarrow} \alm (\lambda', \mu')$ some results obtained in Parts II and IV. We also present a…

Logic · Mathematics 2009-03-30 Paolo Lipparini

Persistent homology encodes the evolution of homological features of a multifiltered cell complex in the form of a multigraded module over a polynomial ring, called a multiparameter persistence module, and quantifies it through invariants…

Algebraic Topology · Mathematics 2026-03-24 Andrea Guidolin , Claudia Landi