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Related papers: Comparing forcing approaches to dense ideals

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We introduce the idea of a coherent adequate set of models, which can be used as side conditions in forcing. As an application we define a forcing poset which adds a square sequence on $\omega_2$ using finite conditions.

Logic · Mathematics 2014-06-13 John Krueger

Building on previous work of [BPS] we investigate $\sigma$-closed partial orders of size continuum. We provide both an internal and external characterization of such partial orders by showing that (1) every $\sigma$-closed partial order of…

Logic · Mathematics 2013-03-05 Bohuslav Balcar , Michal Doucha , Michael Hrušák

We answer a question of Woodin by showing that assuming an inaccessible cardinal $\kappa$ which is a limit of ${<}\kappa$-supercompact cardinals exists, there is a stationary set preserving forcing $\mathbb{P}$ so that $V^{\mathbb…

Logic · Mathematics 2024-03-15 Andreas Lietz

Measurability with respect to ideals is tightly connected with absoluteness principles for certain forcing notions. We study a uniformization principle that postulates the existence of a uniformizing function on a large set, relative to a…

Logic · Mathematics 2022-05-31 Sandra Müller , Philipp Schlicht

This paper presents the main results in my Ph.D. thesis. In what follows several proofs of SCH are presented introducing a family of covering properties which implies both SCH and the failure of various forms of square. These covering…

Logic · Mathematics 2007-05-23 Matteo Viale

In this paper we consider the Foreman's maximality principle, which says that any non-trivial forcing notion either adds a new real or collapses some cardinals. We prove the consistency of some of its consequences. We prove that it is…

Logic · Mathematics 2016-04-05 Mohammad Golshani , Yair Hayut

Justin Moore's weak club-guessing principle $\mho$ admits various possible generalizations to the second uncountable cardinal. One of them was shown to hold in ZFC by Shelah. A stronger one was shown to follow from several consequences of…

Logic · Mathematics 2024-07-29 Ido Feldman

We introduce a two-parameter modification of the cofinality invariant of ideals. This allows us to include the interaction of a pair of ideals in the study of base-like structures. We find the values (cardinal numbers or well-known cardinal…

General Topology · Mathematics 2025-02-13 Adam Marton , Miroslav Repický

In this short note, we shall prove some observations regarding the connection between indestructible $\omega_1$-guessing models and the $\omega_1$-approximation property of forcing notions.

Logic · Mathematics 2022-02-18 Rahman Mohammadpour

For a relational structure ${\mathbb X}$ we investigate the partial order $\langle {\mathbb P} ({\mathbb X}) ,\subset \rangle$, where ${\mathbb P} ({\mathbb X}):=\{ f[X]: f\in \mathop{\rm Emb}\nolimits ({\mathbb X})\}$. Here we consider…

Logic · Mathematics 2024-04-24 Miloš S. Kurilić

We develop a forcing poset with finite conditions which adds a partial square sequence on a given stationary set, with adequate sets of models as side conditions. We then develop a kind of side condition product forcing for simultaneously…

Logic · Mathematics 2018-10-26 John Krueger

We introduce more properties of forcing notions which imply that their lambda-support iterations are lambda-proper, where lambda is an inaccessible cardinal. This paper is a direct continuation of section A.2 of math.LO/0210205. As an…

Logic · Mathematics 2013-01-04 Andrzej Roslanowski , Saharon Shelah

Given a Fra\"{i}ss\'{e} class $\mathcal{K}$ and an infinite cardinal $\kappa,$ we define a forcing notion which adds a structure of size $\kappa$ using elements of $\mathcal{K}$, which extends the Fra\"{i}ss\'{e} construction in the case…

Logic · Mathematics 2021-09-24 Mohammad Golshani

Let $\mathcal{SN}$ be the $\sigma$-ideal of the strong measure zero sets of reals. We present general properties of forcing notions that allow to control of the additivity of $\mathcal{SN}$ after finite support iterations. This is applied…

Logic · Mathematics 2025-08-21 Jörg Brendle , Miguel A. Cardona , Diego A. Mejía

A diagonal version of the strong reflection principle is introduced, along with fragments of this principle associated to arbitrary forcing classes. The relationships between the resulting principles and related principles, such as the…

Logic · Mathematics 2021-08-11 Sean Cox , Gunter Fuchs

Forcing axioms are generalizations of Baire category principles that allow one to intersect more dense open sets and to do so in a wider variety of circumstances. In this paper we introduce two new forcing axioms related to posets which…

Logic · Mathematics 2025-02-05 Thomas Gilton

In this paper it is introduced a generic large cardinal akin to I0, and its consequences are analyzed in the case that $\aleph_\omega$ is such a generic large cardinal. In this case $\aleph_\omega$ is J\'{o}nsson, and in a choiceless inner…

Logic · Mathematics 2017-12-19 Vincenzo Dimonte

For certain weak versions of the Axiom of Choice (most notably, the Boolean Prime Ideal theorem), we obtain equivalent formulations in terms of partial orders, and filter-like objects within them intersecting certain dense sets or…

Logic · Mathematics 2019-03-27 David Fernández-Bretón , Elizabeth Lauri

The Fon-Der-Flaass action partitions the order ideals of a poset into disjoint orbits. For a product of two chains, Propp and Roby observed --- across orbits --- the mean cardinality of the order ideals within an orbit to be invariant. That…

Combinatorics · Mathematics 2015-09-29 David B. Rush , Kelvin Wang

We construct a homogeneous subspace of $2^\omega$ whose complement is dense in $2^\omega$ and rigid. Using the same method, assuming Martin's Axiom, we also construct a countable dense homogeneous subspace of $2^\omega$ whose complement is…

General Topology · Mathematics 2014-10-03 Andrea Medini , Jan van Mill , Lyubomyr Zdomskyy