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Related papers: An independence theorem for NTP2 theories

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We show that approximations of strict order can calibrate the fine structure of genericity. Particularly, we find exponential behavior within the $\mathrm{NSOP}_{n}$ hierarchy from model theory. Let $0$-$\eth$-independence denote…

Logic · Mathematics 2023-05-31 Scott Mutchnik

In a previous paper we developed the notions of th-independence and \th-ranks which define a geometric independence relation in a class of theories which we called ``rosy''. We proved that rosy theories include simple and o-minimal theories…

Logic · Mathematics 2007-05-23 Alf Onshuus

We develop the theory of generically stable types, independence relation based on nonforking and stable weight in the context of dependent (NIP) theories.

Logic · Mathematics 2008-02-01 Alexander Usvyatsov

A relevant thesis is that for the family of complete first order theories with NIP (i.e. without the independence property) there is a substantial theory, like the family of stable (and the family of simple) first order theories. We examine…

Logic · Mathematics 2007-05-23 Saharon Shelah

We give definitions of the properties OP, IP, $k$-TP, TP$_1$, $k$-TP$_2$, SOP$_1$, SOP$_2$ and SOP$_3$ in positive logic, and prove various implications and equivalences between them. We also provide a characterisation of stability in…

Logic · Mathematics 2026-02-11 Anna Dmitrieva , Francesco Gallinaro , Mark Kamsma

We develop the theory of Kim-independence in the context of NSOP$_{1}$ theories satsifying the existence axiom. We show that, in such theories, Kim-independence is transitive and that $\ind^{K}$-Morley sequences witness Kim-dividing. As…

Logic · Mathematics 2023-06-05 Artem Chernikov , Byunghan Kim , Nicholas Ramsey

We initiate a systematic study of \emph{generic stability independence} and introduce the class of \emph{treeless theories} in which this notion of independence is particularly well-behaved. We show that the class of treeless theories…

Logic · Mathematics 2023-05-30 Itay Kaplan , Nicholas Ramsey , Pierre Simon

Just as Lascar's notion of abstract rank axiomatizes the U-rank, we propose axioms for the ranks $SU^d$ and $SU^f$, the foundation ranks of dividing and forking. We study the relationships between these axioms. As with superstable, we…

Logic · Mathematics 2022-02-15 Santiago Cárdenas-Martín , Rafel Farré

This paper builds model-theoretic tools to detect changes in complexity among the simple theories. We develop a generalization of dividing, called shearing, which depends on a so-called context c. This leads to defining c-superstability, a…

Logic · Mathematics 2021-07-06 M. Malliaris , S. Shelah

We study forking, Lascar strong types, Keisler measures and definable groups, under an assumption of $NIP$ (not the independence property), continuing aspects of math.LO/0607442. Among key results are: (i) if $p = tp(b/A)$ does not fork…

Logic · Mathematics 2009-01-29 Ehud Hrushovski , Anand Pillay

A brief introduction to the theory of ordered sets and lattice theory is given. To illustrate proof techniques in the theory of ordered sets, a generalization of a conjecture of Daykin and Daykin, concerning the structure of posets that can…

Combinatorics · Mathematics 2009-09-25 Jonathan David Farley

For $n\geq 3$, define $T_n$ to be the theory of the generic $K_n$-free graph, where $K_n$ is the complete graph on $n$ vertices. We prove a graph theoretic characterization of dividing in $T_n$, and use it to show that forking and dividing…

Logic · Mathematics 2017-10-18 Gabriel Conant

Structural independence is the (conditional) independence that arises from the structure rather than the precise numerical values of a distribution. We develop this concept and relate it to $d$-separation and structural causal models.…

Probability · Mathematics 2025-06-24 Matthias Georg Mayer

A new notion of independence relation is given and associated to it, the class of flat theories, a subclass of strong stable theories including the superstable ones is introduced. More precisely, after introducing this independence…

Logic · Mathematics 2018-04-18 Daniel Palacín , Saharon Shelah

We give several characterizations of when a complete first-order theory $T$ is monadically NIP, i.e. when expansions of $T$ by arbitrary unary predicates do not have the independence property. The central characterization is a condition on…

Logic · Mathematics 2026-05-06 Samuel Braunfeld , Michael C. Laskowski

Following the types-as-sets paradigm, we present a mechanized embedding of dependent function types with a hierarchy of universes into schematic first-order logic with equality, with axiom schemas of Tarski-Grothendieck set theory. We carry…

Logic in Computer Science · Computer Science 2026-03-16 Yunsong Yang , Simon Guilloud , Viktor Kunčak

We regard a geometric theory classified by a topos as a syntactic presentation for the topos and develop tools for finding such presentations. Extensions of geometric theories, which can add axioms, symbols and sorts, are treated as objects…

Category Theory · Mathematics 2022-06-23 Matthias Hutzler

A dependent theory is a (first order complete theory) T which does not have the independence property. A main result here is: if we expand a model of T by the traces on it of sets definable in a bigger model then we preserve its being…

Logic · Mathematics 2013-02-20 Saharon Shelah

In the classification of complete first-order theories, many dividing lines have been defined in order to understand the complexity and the behavior of some classes of theories. In this paper, using the concept of patterns of consistency…

Logic · Mathematics 2025-07-08 Michele Bailetti

In this paper we develop three different subjects. We study and prove alternative versions of Hrushovski's "Stabilizer Theorem", we generalize part of the basic theory of definably amenable NIP groups to NTP2 theories, and finally, we use…

Logic · Mathematics 2018-01-03 Samaria Montenegro , Alf Onshuus , Pierre Simon