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We give topological characterizations of filters $F$ on $w$ such that the Mathias forcing $M_F$ adds no dominating reals or preserves ground model unbounded families. This allows us to answer some questions of Brendle, Guzm\'an,…

Logic · Mathematics 2015-12-29 David Chodounský , Dušan Repovš , Lyubomyr Zdomskyy

We prove that the generic maximal independent family obtained by iteratively forcing with the Mathias forcing relative to diagonalization filters is densely maximal. Moreover, by choosing the filters with some care one can ensure the family…

Logic · Mathematics 2023-06-19 Vera Fischer , Corey Bacal Switzer

We introduce Gowers--Matet forcing with a finite sequence of pairwise non-isomorphic Ramsey ultrafilters over $\omega$, and with this forcing we settle the long-standing problem of the spectrum of numbers near-coherence classes. We prove…

Logic · Mathematics 2019-07-31 Heike Mildenberger

A variety of possible extensions of mappings between posets to their Dedekind order completion is presented. One of such extensions has recently been used for solving large classes of nonlinear systems of partial differential equations with…

General Mathematics · Mathematics 2007-05-23 Elemer E Rosinger

We consider here Easton support iterations of Prikry type forcing notions. New ways of constructing normal ultrafilters in extensions are presented. It turns out that, in contrast with other supports, seemingly unrelated measures or…

Logic · Mathematics 2023-01-31 Moti Gitik , Eyal Kaplan

We give a broad survey of inequalities for the number of linear extensions of finite posets. We review many examples, discuss open problems, and present recent results on the subject. We emphasize the bounds, the equality conditions of the…

Combinatorics · Mathematics 2025-06-05 Swee Hong Chan , Igor Pak

This is an overview about a method of constructing ccc forcings: Suppose first that a continuous, commutative system of complete embeddings between countable forcings indexed along $\omega_1$ is given. Then its direct limit satisfies ccc by…

Logic · Mathematics 2008-11-07 Bernhard Irrgang

We continue Gitik, Kanovei and Koepke's work and study sets in generic extensions by the Magidor forcing and by the Prikry forcing with non-normal ultrafilters.

Logic · Mathematics 2021-09-22 Tom Benhamou , Moti Gitik

We introduce a class of proper posets which is preserved under countable support iterations, includes $\omega^\omega$-bounding, Cohen, Miller, and Mathias posets associated to filters with the Hurewicz covering properties, and has the…

Logic · Mathematics 2022-10-21 Dušan Repovš , Lyubomyr Zdomskyy

We introduce a forcing that adds a $\square(\aleph_2,\aleph_0)$-sequence with countable conditions under CH. Assuming the consistency of a weakly compact cardinal, we can find a forcing extension by our new poset in which both…

Logic · Mathematics 2026-03-17 Maxwell Levine

We prove some iteration theorems for a certain class of $\kappa^+$-cc forcing posets.

Logic · Mathematics 2018-11-14 James Cummings , Mirna Džamonja , Itay Neeman

We introduce several new constructions of finite posets with the number of linear extensions given by generalized continued fractions. We apply our results to the problem of the minimum number of elements needed for a poset with a given…

Combinatorics · Mathematics 2024-08-01 Swee Hong Chan , Igor Pak

In this paper we answer several questions in arXiv:2102.06009 regarding density variants of Mathias and Silver forcing. These questions include whether each of the forcing is proper, add dominating real, or add Cohen real. We also…

Logic · Mathematics 2025-07-25 Shixiao Liu

We present a method to iterate finitely splitting lim-sup tree forcings along non-wellfounded linear orders. We apply this method to construct a forcing (without using an inaccessible or amalgamation) that makes all definable sets of reals…

Logic · Mathematics 2011-10-18 Jakob Kellner , Saharon Shelah

We present a version with non-definable forcing notions of Shelah's theory of iterated forcing along a template. Our main result, as an application, is that, if $\kappa$ is a measurable cardinal and $\theta<\kappa<\mu<\lambda$ are…

Logic · Mathematics 2015-06-23 Diego Alejandro Mejía

In this paper we consider the classical problem of computing linear extensions of a given poset which is well known to be a difficult problem. However, in our setting the elements of the poset are multivariate polynomials, and only a small…

Combinatorics · Mathematics 2021-03-05 Shane Kepley , Konstantin Mischaikow , Lun Zhang

We study the Mathias--Prikry and the Laver type forcings associated with filters and coideals. We isolate a crucial combinatorial property of Mathias reals, and prove that Mathias--Prikry forcings with summable ideals are all mutually…

Logic · Mathematics 2017-03-07 David Chodounský , Osvaldo Guzmán , Michael Hrušák

We prove that the strong polarized relation for the continuum holds for $\aleph_0$ and for every supercompact cardinal. We use iteration of Mathias forcing.

Logic · Mathematics 2012-06-13 Shimon Garti , Saharon Shelah

We develop a new method for building forcing iterations with symmetric systems of structures as side conditions. Using our method we prove that the forcing axiom for the class of all the small finitely proper posets is compatible with a…

Logic · Mathematics 2015-01-26 David Asperó , Miguel Angel Mota

In this paper, we introduce and study a new extragradient iterative process for finding a common element of the set of fixed points of an infinite family of nonexpansive mappings and the set of solutions of a variational inequality for an…

Functional Analysis · Mathematics 2014-05-22 Ibrahim Karahan , Murat Ozdemir
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