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Related papers: Existence in NSOP$_1$ theories

200 papers

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 prove the existence of flips in dimension n, contingent on the termination of real flips in dimension n-1.

Algebraic Geometry · Mathematics 2007-05-23 Christopher Hacon , James McKernan

We show that the theorem of the three perpendiculars holds in any n-dimensional space form.

Metric Geometry · Mathematics 2013-07-08 Jin-ichi Itoh , Joel Rouyer , Costin Vilcu

In this note, we prove that Kim-dividing over models is always witnessed by a coheir Morley sequence in NATP theories. Following the strategy of Chernikov and Kaplan [8], we obtain some corollaries which hold in NATP theories. Namely, (i)…

Logic · Mathematics 2026-03-04 Joonhee Kim , Hyoyoon Lee

We give an example of an NIP theory $T$ in which there is a formula that does not fork over $\varnothing$ but has measure $0$ under any global $\varnothing$-invariant Keisler measure, and we show that this cannot occur if $T$ is also…

Logic · Mathematics 2023-07-21 Anand Pillay , Atticus Stonestrom

We give three counterexamples to the folklore claim that in an arbitrary theory, if a complete type $p$ over a set $B$ does not divide over $C\subseteq B$, then no extension of $p$ to a complete type over $\text{acl}(B)$ divides over $C$.…

Logic · Mathematics 2024-11-20 Gabriel Conant , Alex Kruckman

I present a criterion for all-order finiteness in N=1 SYM theories. Three applications are given; they yield all-order finite N=1 SYM models with global symmetries of the superpotential.

High Energy Physics - Phenomenology · Physics 2009-10-28 C. Lucchesi

We prove that in theories without the tree property of the second kind (which include dependent and simple theories) forking and dividing over models are the same, and in fact over any extension base. As an application we show that…

Logic · Mathematics 2011-03-22 Artem Chernikov , Itay Kaplan

We prove the existence of a model companion of the two-sorted theory of $c$-nilpotent Lie algebras over a field satisfying a given theory of fields. We describe a language in which it admits relative quantifier elimination up to the field…

Logic · Mathematics 2025-07-18 Christian d'Elbée , Isabel Müller , Nicholas Ramsey , Daoud Siniora

Simple argument in favour of unitarity, to all orders, of space-like noncommutative theory is given.

High Energy Physics - Theory · Physics 2007-05-23 Piotr Kosinski , Pawel Maslanka

This paper continues math.LO/0009087. We present a rank function for NSOP_1 theories and give an example of a theory which is NSOP_1 but not simple. We also investigate the connection between maximality in the ordering <^* among complete…

Logic · Mathematics 2007-05-23 Saharon Shelah , Alex Usvyatsov

We give a concise proof of the fundamental theorem of smoothing theory in the special case when a smoothing exists.

Algebraic Topology · Mathematics 2010-07-09 John R. Klein , Bruce Williams

We establish several results regarding dividing and forking in NTP2 theories. We show that dividing is the same as array-dividing. Combining it with existence of strictly invariant sequences we deduce that forking satisfies the chain…

Logic · Mathematics 2013-08-14 Itaï Ben Yaacov , Artem Chernikov

We give an example of an SOP theory $T$, such that any $L(M)$-formula $\varphi(x,y)$ with $|y|=1$ is NSOP. We show that any such $T$ must have the independence property. We also give a simplified proof of Lachlan's theorem that if every…

Logic · Mathematics 2025-07-15 Will Johnson

We prove that every many-sorted $\omega$-categorical theory is completely interpretable in a one-sorted $\omega$-categorical theory. As an application, we give a short proof of the existence of non $G$--compact $\omega$-categorical…

Logic · Mathematics 2011-03-21 Enrique Casanovas , Rodrigo Peláez , Martin Ziegler

We introduce some properties describing dependence in indiscernible sequences: $F_{ind}$ and its dual $F_{Mb}$, the definable Morley property, and $n$-resolvability. Applying these properties, we establish the following results: We show…

Logic · Mathematics 2026-04-29 John Baldwin , James Freitag , Scott Mutchnik

The main purpose of this paper is to present a new and more uniform model-theoretic/combinatorial proof of the theorem ([5]): The randomization $T^{R}$ of a complete first-order theory $T$ with $NIP$ is a (complete) first-order continuous…

Logic · Mathematics 2026-01-01 Karim Khanaki , Massoud Pourmahdian

Riemann Existence Theorems for Galois covers of Mumford curves by Mumford curves are stated and proven. As an application, all finite groups are realised as full automorphism groups of Mumford curves in characteristic zero.

Algebraic Geometry · Mathematics 2007-07-18 Patrick Erik Bradley

By a [$K$-]approximate subring of a ring we mean an additively symmetric subset $X$ such that $X \cdot X \cup (X + X)$ is covered by finitely many [resp.\ $K$] additive translates of $X$. We prove a structure theorem for finite approximate…

Rings and Algebras · Mathematics 2026-04-07 Krzysztof Krupiński , Simon Machado

This paper is the $K$-theoretic analogue of a recent new proof, given by the first named author, of Peterson-Lam-Shimozono's theorem via Savelyev's generalization of Seidel representations. The outcome is a new proof of…

Algebraic Geometry · Mathematics 2022-02-01 Chi Hong Chow , Naichung Conan Leung