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Related papers: More on almost Souslin Kurepa trees

200 papers

We show that the existence of an almost Souslin Kurepa tree is consistent with $ZFC$. We also prove their existence in $L$. These results answer two questions from Zakrzewski.

Logic · Mathematics 2015-10-13 Mohammad Golshani

We show it is consistent that there is a Souslin tree $S$ such that after forcing with $S$, $S$ is Kurepa and for all clubs $C \subset \omega_1$, $S\upharpoonright C$ is rigid. This answers Fuchs's questions in Club degrees of rigidity and…

Logic · Mathematics 2023-06-21 Hossein Lamei Ramandi

We analyze the forcing notion $\mathcal P$ of finite matrices whose rows consists of isomorphic countable elementary submodels of a given structure of the form $H_{\theta}$. We show that forcing with this poset adds a Kurepa tree $T$.…

Logic · Mathematics 2015-08-18 Borisa Kuzeljevic , Stevo Todorcevic

For uncountable downwards closed subtrees $U$ and $W$ of an $\omega_1$-tree $T$, we say that $U$ and $W$ are strongly almost disjoint if their intersection is a finite union of countable chains. The tree $T$ is strongly non-saturated if…

Logic · Mathematics 2025-09-09 John Krueger , Eduardo Martinez Mendoza

We introduce an abstract framework for forcing over a free Suslin tree with suborders of products of forcings which add some structure to the tree using countable approximations. The main ideas of this framework are consistency, separation,…

Logic · Mathematics 2025-01-20 John Krueger , Sarka Stejskalova

We analyze a countable support product of a free Suslin tree which turns it into a highly rigid Kurepa tree with no Aronszajn subtree. In the process, we introduce a new rigidity property for trees, which says roughly speaking that any…

Logic · Mathematics 2025-09-17 John Krueger

Building on recent work of Krueger and the second author, we prove the consistency of the Guessing Model Principle at $\omega_2$ together with the existence of an almost Kurepa Suslin tree. In particular, it is consistent that the Guessing…

Logic · Mathematics 2026-03-12 Chris Lambie-Hanson , Šárka Stejskalová

In this paper we investigate the problem of the distributivity of Kurepa trees. We show that it is consistent that there are Kurepa trees and for every Kurepa tree there is a small forcing notion which adds a branch to it without collapsing…

Logic · Mathematics 2024-01-02 Itamar Giron , Yair Hayut

We prove that it is consistent that there exists a Kurepa tree $T$ such that ${}^{\omega_1}2$ is a continuous image of the topological space $[T]$ consisting of all cofinal branches of $T$ with respect to the cone topologies. This result…

Logic · Mathematics 2025-07-03 John Krueger

In this note we answer a question of Kunen (15.13 [Mi91]) showing that it is consistent that there are full Souslin trees

Logic · Mathematics 2008-02-03 Saharon Shelah

An $\aleph_1$-Souslin tree is a complicated combinatorial object whose existence cannot be decided on the grounds of ZFC alone. But 15 years after Tennenbaum and independently Jech devised notions of forcing for introducing such a tree,…

Logic · Mathematics 2019-09-18 Ari Meir Brodsky , Assaf Rinot

In the paper we probe the possibilities of creating a Kurepa tree in a generic extension of a model of CH plus no Kurepa trees by an omega_1-preserving forcing notion of size at most omega_1. In the first section we show that in the Levy…

Logic · Mathematics 2016-09-06 Renling Jin , Saharon Shelah

We show that many countable support iterations of proper forcings preserve Souslin trees. We establish sufficient conditions in terms of games and we draw connections to other preservation properties. We present a proof of preservation…

Logic · Mathematics 2013-09-03 Heike Mildenberger , Saharon Shelah

We introduce a variant of the Kurepa family. We then use one such family to construct a ccc indestructible property associated with a complete coherent Suslin tree $S$. Moreover, in every ccc forcing extension that preserves Suslin of $S$,…

Logic · Mathematics 2026-01-01 Yinhe Peng

We study the relationship between a $\kappa$-Souslin tree $T$ and its reduced powers $T^\theta/\mathcal U$. Previous works addressed this problem from the viewpoint of a single power $\theta$, whereas here, tools are developed for…

Logic · Mathematics 2018-11-28 Ari Meir Brodsky , Assaf Rinot

A forest is a generalization of a tree, and here we consider the Aronszajn and Suslin properties for forests. We focus on those forests satisfying coherence, a local smallness property. We show that coherent Aronszajn forests can be…

Logic · Mathematics 2019-01-07 Monroe Eskew

In this paper we aim to compare Kurepa trees and Aronszajn trees. Moreover, we analyze the affect of large cardinal assumptions on this comparison. Using the the method of walks on ordinals, we will show it is consistent with ZFC that there…

Logic · Mathematics 2023-10-10 Hossein Lamei Ramandi , Stevo Todorcevic

We give two consistent constructions of trees $T$ whose finite power $T^{n+1}$ is sharply different from $T^n$: 1. An $\aleph_1$-tree $T$ whose interval topology $X_T$ is perfectly normal, but $(X_T)^2$ is not even countably metacompact. 2.…

Logic · Mathematics 2026-04-22 Ari Meir Brodsky , Assaf Rinot , Shira Yadai

We consider a transitive relation on the power set of $\omega_1$ and show if there is a maximal element with respect to this relation then there is a Kurepa tree with no Aronszajn subtree. We also show that if there is a maximal subset of…

Logic · Mathematics 2023-10-20 Hossein Lamei Ramandi , Stevo Todorcevic

We present a weak sufficient condition for the existence of Souslin trees at successor of regular cardinals. The result is optimal and simultaneously improves an old theorem of Gregory and a more recent theorem of the author.

Logic · Mathematics 2018-12-21 Assaf Rinot
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