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Related papers: Type decomposition in NIP theories

200 papers

We study stable like behaviour in first order theories without the independence property. We introduce generically stable measures, give characterizatiions, and show their ubiquity. We also introduce generic compact domination. We also…

Logic · Mathematics 2010-02-26 Ehud Hrushovski , Anand Pillay , Pierre Simon

Motivated by the classical type decomposition of von Neumann algebras, and various more recent extensions to other structures, we develop a type decomposition theory for general posets.

Rings and Algebras · Mathematics 2017-02-10 Tristan Bice

We give a general exposition of model theoretic connected components of groups. We show that if a group G has NIP, then there exists the smallest invariant (over some small set) subgroup of G with bounded index (Theorem 5.3). This result…

Logic · Mathematics 2010-02-09 Jakub Gismatullin

We study generically stable measures in the local, NIP context. We show that in this setting, a measure is generically stable if and only if it admits a natural finite approximation.

Logic · Mathematics 2019-09-18 Kyle Gannon

A definable type of a first-order theory is the same as a section (retraction) of the simplicial path space (decalage) of its space of types viewed as a simplicial topological space; as is well-known, in the category of simplicial sets such…

Category Theory · Mathematics 2023-03-31 Misha Gavrilovich

This paper is a modified chapter of the author's Ph.D. thesis. We introduce the notions of sequentially approximated types and sequentially approximated Keisler measures. As the names imply, these are types which can be approximated by a…

Logic · Mathematics 2021-12-13 Kyle Gannon

We study some basic properties of sofic-Dyck shifts and finite-type-Dyck shifts. We prove that the class of sofic-Dyck shifts is stable under proper conjugacies. We prove a Decomposition Theorem of a proper conjugacy between edge-Dyck…

Formal Languages and Automata Theory · Computer Science 2013-11-19 Marie-Pierre Béal , Michel Blockelet , Cǎtǎlin Dima

We show that, for a pseudo-proper smooth noetherian formal scheme $\mathfrak{X}$ over a positive characteristic $p$ field, its truncated De Rham complex up to the characteristic $p$ is decomposable. Moreover, if the dimension of…

Algebraic Geometry · Mathematics 2021-11-11 Leovigildo Alonso , Ana Jeremias , Marta Perez

This paper is a contribution to "neo-stability" type of result for abstract elementary classes. Under certain set theoretic assumptions, we propose a definition and a characterization of NIP in AECs. The class of AECs with NIP properly…

Logic · Mathematics 2025-10-28 Wentao Yang

We introduce and study semi-equational and weakly semi-equational theories, generalizing equationality in stable theories (in the sense of Srour) to the NIP context. In particular, we establish a connection to distality via one-sided strong…

Logic · Mathematics 2023-05-08 Artem Chernikov , Alex Mennen

Informed by our understanding of the tt-geometry of permutation modules, we investigate the proper definition of the `stable permutation category' of a finite group. Then we prove that this category decomposes over cyclic and generalized…

Representation Theory · Mathematics 2026-04-21 Paul Balmer , Martin Gallauer

We present a soundness theorem for a dependent type theory with context constants with respect to an indexed category of (finite, abstract) simplical complexes. The point of interest for computer science is that this category can be seen to…

Logic · Mathematics 2020-07-08 Henrik Forssell , Håkon Robbestad Gylterud , David I. Spivak

Assume a complete superstable theory is superstable, and let P be a class of regular types, typically closed under automorphisms of the monster and non-orthogonality. We define the notion of P-NDOP and prove the existence of…

Logic · Mathematics 2014-06-05 Saharon Shelah , Michael C. Laskowski

We find that to the dynamics of a given dissipative system a $p=1$ differential form can be associated with a general decomposition into a potential term and a non-potential residual part. If the residual part is absent the form is closed…

Mathematical Physics · Physics 2025-10-01 Rafael Rangel

Vietoris-Rips and degree Rips complexes are represented as homotopy types by their underlying posets of simplices, and basic homotopy stability theorems are recast in these terms. These homotopy types are viewed as systems (or functors),…

Algebraic Topology · Mathematics 2020-10-28 J. F. Jardine

In this note we study sets of NIP formulas in some theories of fields and valued fields, with a special focus on the sets of quantifier-free and existential formulas. First, we give a new proof of the fact that Separably Closed Valued…

Logic · Mathematics 2026-02-04 Paulo Andrés Soto Moreno

We give some background on uniform pro-p groups and the model theory of profinite NIP groups.

Group Theory · Mathematics 2017-05-23 Tim Clausen , Katrin Tent

This paper aims at developing model-theoretic tools to study interpretable fields and definably amenable groups, mainly in $\mathrm{NIP}$ or $\mathrm{NTP_2}$ settings. An abstract theorem constructing definable group homomorphisms from…

Logic · Mathematics 2025-01-07 Paul Z. Wang

A p-compact group is a mod p homotopy theoretical analogue of a compact Lie group. It is determined the homotopy nilpotency class of a p-compact group having the homotopy type of the $p$-completion of the direct product of spheres.

Algebraic Topology · Mathematics 2007-10-23 Shizuo Kaji , Daisuke Kishimoto

In this paper, we characterize NIP henselian valued fields modulo the theory of their residue field, both in an algebraic and in a model-theoretic way. Assuming the conjecture that every infinite NIP field is either separably closed, real…

Logic · Mathematics 2024-03-14 Sylvy Anscombe , Franziska Jahnke