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Related papers: Finding generically stable measures

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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

In NIP theories, generically stable Keisler measures can be characterized in several ways. We analyze these various forms of "generic stability" in arbitrary theories. Among other things, we show that the standard definition of generic…

Logic · Mathematics 2020-05-22 Gabriel Conant , Kyle Gannon

We develop a theory of generically stable and smooth Keisler measures in NIP metric theories, generalizing the case of classical logic. Using smooth extensions, we verify that fundamental properties of (Borel)-definable measures and the…

Logic · Mathematics 2023-10-11 Aaron Anderson

We prove a number of results relating the concepts of Keisler measures, generic stability, randomizations, and NIP formulas. Among other things, we do the following: (1) We introduce the notion of a Keisler-Morley measure, which plays the…

Logic · Mathematics 2023-09-04 Gabriel Conant , Kyle Gannon , James E. Hanson

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

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 introduce the notions of $rgs$ and $irgs$ as properties of a Keisler measure $\mu$, and prove that they are respectively equivalent to the existence of a generically stable random type that extends $\mu$ and to the fact that its…

Logic · Mathematics 2026-05-18 Karim Khanaki

As consequence of the VC theorem, any pseudo-finite measure over an NIP ultraproduct is generically stable. We demonstrate a converse of this theorem and prove that any finitely approximable measure over an ultraproduct is itself…

Logic · Mathematics 2024-07-08 Kyle Gannon

We study one way in which stable phenomena can exist in an NIP theory. We start by defining a notion of 'pure instability' that we call 'distality' in which no such phenomenon occurs. O-minimal theories and the p-adics for example are…

Logic · Mathematics 2015-09-24 Pierre Simon

We initiate a systematic study of the convolution operation on Keisler measures, generalizing the work of Newelski in the case of types. Adapting results of Glicksberg, we show that the supports of generically stable (or just definable,…

Logic · Mathematics 2021-01-19 Artem Chernikov , Kyle Gannon

The generalized entropic measure, which is optimized by a given arbitrary distribution under the constraints on normalization of the distribution and the finite ordinary expectation value of a physical random quantity, is considered and its…

Statistical Mechanics · Physics 2009-11-10 Sumiyoshi Abe , G. Kaniadakis , A. M. Scarfone

We introduce the notion of dependence, as a property of a Keisler measure, and generalize several results of [HPS13] on generically stable measures (in $NIP$ theories) to arbitrary theories. Among other things, we show that this notion is…

Logic · Mathematics 2025-06-09 Karim Khanaki

We study idempotent measures and the structure of the convolution semigroups of measures over definable groups. We isolate the property of generic transitivity and demonstrate that it is sufficient (and necessary) to develop stable group…

Logic · Mathematics 2025-04-08 Artem Chernikov , Kyle Gannon , Krzysztof Krupiński

We investigate Keisler measures in arbitrary theories. Our initial focus is on Borel definability. We show that when working over countable parameter sets in countable theories, Borel definable measures are closed under Morley products and…

Logic · Mathematics 2023-06-28 Gabriel Conant , Kyle Gannon , James Hanson

We study generically stable types/measures in both classical and continuous logics, and their connection with randomization and modes of convergence of types/measures.

Logic · Mathematics 2025-08-27 Karim Khanaki

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

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

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 prove two results about generically stable types $p$ in arbitrary theories. The first, on existence of strong germs, generalizes results from D. Haskell, E. Hrushovski and D. Macpherson on stably dominated types. The second is an…

Logic · Mathematics 2012-10-23 Hans Adler , Enrique Casanovas , Anand Pillay

We generalize various notions of stability of invariant sets of dynamical systems to invariant measures, by defining a topology on the set of measures. The defined topology is similar, but not topologically equivalent to weak* topology, and…

Dynamical Systems · Mathematics 2008-11-04 Sinisa Slijepcevic
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