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Related papers: Adding highly generic subsets of $\omega_2$

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Starting from a supercompact cardinal we build a model in which $2^{\aleph_{\omega_1}}=2^{\aleph_{\omega_1+1}}=\aleph_{\omega_1+3}$ but there is a jointly universal family of size $\aleph_{\omega_1+2}$ of graphs on $\aleph_{\omega_1+1}$.…

Logic · Mathematics 2016-05-03 Jacob Davis

We give Woodin's original proof that if there exists a $(\kappa+2)-$strong cardinal $\kappa,$ then there is a generic extension of the universe in which $\kappa=\aleph_\omega,$ $GCH$ holds below $\aleph_\omega$ and…

Logic · Mathematics 2016-01-19 Mohammad Golshani

It is true in the Cohen generic extension of L, the constructible universe, that every countable ordinal-definable set of reals belongs to L.

Logic · Mathematics 2018-08-20 Vladimir Kanovei

Abstractly, the generic extensions after $\aleph_\omega$-many Cohen reals and $\aleph_{\omega+1}$-many Cohen reals must be different for reasons of uniform density the relevant Boolean algebras. Nevertheless this is not satisfying and it…

Logic · Mathematics 2025-11-26 Pedro Marun , Saharon Shelah , Corey Bacal Switzer

Starting from the existence of a weakly compact cardinal, we build a generic extension of the universe in which $GCH$ holds and all $\aleph_2$-Aronszajn trees are special and hence there are no $\aleph_2$-Souslin trees. This result answers…

Logic · Mathematics 2024-04-25 David Asperó , Mohammad Golshani

Starting from a stationary set of supercompact cardinals we find a generic extension in which the tree property holds at every regular cardinal between $\aleph_2$ and $\aleph_{\omega^2}$.

Logic · Mathematics 2020-02-06 Yair Hayut

We study certain Banach spaces that are added in the extension by one Cohen real. Specifically, we show that adding just one Cohen real to any model adds a Banach space of density $\aleph_1$ which does not embed into any such space in the…

Logic · Mathematics 2015-05-12 Mirna Džamonja

The purpose of the paper is to produce models V_1 \subset V_2 such that adding kappa-many Cohen reals to V_2 adds lambda Cohen reals to V_1. Some of the results: 1. Suppose that V satisfies GCH, kappa = \cup kappa_n= \cup o(kappa_n). Then…

Logic · Mathematics 2016-09-06 Moti Gitik

Starting with two supercompact cardinals we produce a generic extension of the universe in which a principle that we call ${\rm GM}^+(\omega_3,\omega_1)$ holds. This principle implies ${\rm ISP}(\omega_2)$ and ${\rm ISP}(\omega_3)$, and…

Logic · Mathematics 2019-05-21 Rahman Mohammadpour , Boban Velickovic

In this paper, we study the notion of a generically extendible cardinal, which is a generic version of an extendible cardinal. We prove that the generic extendibility of $\omega_1$ or $\omega_2$ has small consistency strength, but that of a…

Logic · Mathematics 2024-11-26 Toshimichi Usuba

In this paper we first formulate several ``combinatorial principles'' concerning kappa \times omega matrices of subsets of omega and prove that they are valid in the generic extension obtained by adding any number of Cohen reals to any…

Logic · Mathematics 2010-03-17 I. Juhász , Lajos Soukup , Z. Szentmiklóssy

Starting from large cardinals we construct a pair $V_1\subseteq V_2$ of models of $ZFC$ with the same cardinals and cofinalities such that $GCH$ holds in $V_1$ and fails everywhere in $V_2$.

Logic · Mathematics 2015-10-13 Sy David Friedman , Mohammad Golshani

Let $\kappa$ be an infinite cardinal. Then, forcing with $\mathbb{R}(\kappa)$$\times$$\mathbb{R}(\kappa)$ adds a generic filter for $\mathbb{C}(\kappa);$ where $\mathbb{R}(\kappa)$ and $\mathbb{C}(\kappa)$ are the forcing notions for adding…

Logic · Mathematics 2017-01-17 Mohammad Golshani

Assuming that $GCH$ holds and $\kappa$ is $\kappa^{+3}$-supercompact, we construct a generic extension $W$ of $V$ in which $\kappa$ remains strongly inaccessible and $(\alpha^+)^{HOD} < \alpha^+$ for every infinite cardinal $\alpha <…

Logic · Mathematics 2016-01-15 James Cummings , Sy David Friedman , Mohammad Golshani

We construct a generic extension in which the aleph_2 nd canonical function on aleph_1 exists.

Logic · Mathematics 2009-09-25 Thomas Jech , Saharon Shelah

This thesis consists of two parts: the construction of a jointly universal family of graphs, and then an exploration of set-theoretic geology. Firstly we shall construct a model in which…

Logic · Mathematics 2016-05-31 Jacob Davis

We sow that there exists a generic extension of the G\"{o}del's constructible universe in which diamond holds and there exists a subset $Y \subseteq \omega_1$ such that for stationary many $\delta < \omega_1,$ the set $Y \cap \delta$ is not…

Logic · Mathematics 2023-11-07 Mohammad Golshani , Saharon Shelah

In this paper, we investigate connections between structures present in every generic extension of the universe $V$ and computability theory. We introduce the notion of {\em generic Muchnik reducibility} that can be used to to compare the…

Logic · Mathematics 2014-12-11 Julia Knight , Antonio Montalban , Noah Schweber

We show that if we add any number of Cohen reals to the ground model then, in the generic extension, a locally compact scattered space has at most (2^{aleph_0})^V many levels of size omega. We also give a complete ZFC characterization of…

Logic · Mathematics 2007-05-23 István Juhász , Saharon Shelah , Lajos Soukup , Zoltán Szentmiklóssy

Foreman proved the Duality Theorem, which gives an algebraic characterization of certain ideal quotients in generic extensions. As an application he proved that generic supercompactness of $\omega_1$ is preserved by any proper forcing. We…

Logic · Mathematics 2015-08-04 Brent Cody , Sean Cox
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