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Related papers: On \omega-categorical simple theories

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Answering a question of Junker and Ziegler, we construct a countable first order structure which is not omega-categorical, but does not have any proper non-trivial reducts, in either of two senses (model-theoretic, and group-theoretic). We…

Logic · Mathematics 2015-02-27 Manuel Bodirsky , Dugald Macpherson

We consider the equivariant Kasparov category associated to an \'etale groupoid, and by leveraging its triangulated structure we study its localization at the "weakly contractible" objects, extending previous work by R. Meyer and R. Nest.…

K-Theory and Homology · Mathematics 2024-12-23 Christian Bönicke , Valerio Proietti

In a recent Letter [PRL 113, 120404 (2014)] Ferrie and Combes claimed to show "that weak values are not inherently quantum, but rather a purely statistical feature of pre- and post-selection with disturbance." In this Comment I will show…

Quantum Physics · Physics 2014-09-19 Lev Vaidman

This work provides some general theorems about unconditional and conditional weak convergence of empirical processes in the case of Poisson sampling designs. The theorems presented in this work are stronger than previously published…

Statistics Theory · Mathematics 2019-06-12 Leo Pasquazzi

We show that there is a low T-upper bound for the class of K-trivial sets, namely those which are weak from the point of view of algorithmic randomness. This result is a special case of a more general characterization of ideals in the…

Logic · Mathematics 2009-02-03 Antonin Kucera , Theodore A. Slaman

We study the model theory of vector spaces with a bilinear form over a fixed field. For finite fields this can be, and has been, done in the classical framework of full first-order logic. For infinite fields we need different logical…

Logic · Mathematics 2023-03-24 Mark Kamsma

In this paper we present new, short and elementary proofs of the famous projection and section theorems that are used in Stochastic Calculus.

Probability · Mathematics 2024-12-03 Stefanos Theodorakopoulos

We define weak stable Kim-forking, a notion that generalizes stable forking to the context of NSOP1 theories. We adapt some of the known results on stable forking to this context.

Logic · Mathematics 2025-11-03 Yvon Bossut

Let ${\mathscr M}(p)$ $(p=2,3,\ldots)$ be the singlet vertex operator algebra and $\omega$ its conformal vector. We classify the simple weak ${\mathscr M}(p)$-modules with a non-zero element $u$ such that for some integer $s\geq 2$,…

Quantum Algebra · Mathematics 2020-03-13 Kenichiro Tanabe

In this note, we construct torsion-free countable, amenable, weakly mixing groups, which answer a question of V. Bergelson. Some results related to verbal subgroups and crystallographic groups are also presented.

Dynamical Systems · Mathematics 2016-07-04 Rostislav Grigorchuk , Rostyslav Kravchenko , Alexander Olshanskii

We prove that there are only finitely many distinct semi-simple gauge groups and matter representations possible in consistent 6D chiral (1,0) supergravity theories with one tensor multiplet. The proof relies only on features of the…

High Energy Physics - Theory · Physics 2015-05-14 Vijay Kumar , Washington Taylor

There is a well-known correspondence between coherent theories (and their interpretations) and coherent categories (resp. functors), hence the (2,1)-category $\mathbf{Coh_{\sim}}$ (of small coherent categories, coherent functors and all…

Category Theory · Mathematics 2021-04-28 Kristóf Kanalas

We continue the study of properties related to monotone countable paracompactness, investigating various monotone versions of $\delta$-normality. We factorize monotone normality and stratifiability in terms of these weaker properties.

General Topology · Mathematics 2007-12-21 Lylah Haynes , Chris Good

The Axiom of Dependent Choice $\mathsf{DC}$ and the Axiom of Countable Choice $\mathsf{AC}_\omega$ are two weak forms of the Axiom of Choice that can be stated for a specific set: $\mathsf{DC}(X)$ asserts that any total binary relation on…

Logic · Mathematics 2025-01-07 Alessandro Andretta , Lorenzo Notaro

A Cayley graph for a group $G$ is CCA if every automorphism of the graph that preserves the edge-orbits under the regular representation of $G$ is an element of the normaliser of $G$. A group $G$ is then said to be CCA if every connected…

Group Theory · Mathematics 2017-03-24 Luke Morgan , Joy Morris , Gabriel Verret

This paper is a study of weighted counting of the solutions of acyclic conjunctive queries ($\ACQ$). The unweighted quantifier free version of this problem is known to be tractable (for combined complexity), but it is also known that…

Computational Complexity · Computer Science 2011-12-08 Arnaud Durand , Stefan Mengel

In this note the proof-theoretic ordinal of the well-ordering principle for the normal functions ${\sf g}$ on ordinals is shown to be equal to the least fixed point of ${\sf g}$. Moreover corrections to the previous paper are made.

Logic · Mathematics 2019-05-22 Toshiyasu Arai

A combinatorial principle CECA is formulated and its equivalence with GCH+ certain weakenings of Box_lambda for singular lambda is proved. CECA is used to show that certain ``almost point- < tau'' families can be refined to point- < tau…

We define a nontrivial version of the square principle $\Box_\omega$, which we then show consistent by means of forcing with finite conditions. This paper has been withdrawn by the author due to the fact that the presented $\Box_\omega$ can…

Logic · Mathematics 2026-04-13 Gregor K. Dolinar , Mirna Džamonja

The (prefix-free) Kolmogorov complexity of a finite binary string is the length of the shortest description of the string. This gives rise to some `standard' lowness notions for reals: A is K-trivial if its initial segments have the lowest…

Logic · Mathematics 2014-10-15 Ian Herbert