English
Related papers

Related papers: Diamond on Kurepa trees

200 papers

We prove the consistency of the failure of the weak diamond $\Phi_\lambda$ at strongly inaccessible cardinals. On the other hand, we show that the very weak diamond $\Psi_\lambda$ is equivalent to the statement $2^{<\lambda}<2^\lambda$ and…

Logic · Mathematics 2019-03-12 Omer Ben-Neria , Shimon Garti , Yair Hayut

I show that it is consistent relative to the consistency of a Mahlo cardinal that Martin's axiom holds at $\omega_2$, but the weak Kurepa Hypothesis fails. This answers a question posed by Honzik, Lambie-Hanson and Stejskalov\'a. The…

Logic · Mathematics 2024-11-12 Rahman Mohammadpour

Starting from suitable large cardinals, we force the failure of (weak) diamond at the least inaccessible cardinal. The result improves an unpublished theorem of Woodin and a recent result of Ben-Neria, Garti and Hayut.

Logic · Mathematics 2021-01-27 Mohammad Golshani

We prove that, consistently, there exists a weakly but not strongly inaccessible cardinal $\lambda$ for which the sequence $\langle 2^\theta:\theta<\lambda\rangle$ is not eventually constant and the weak diamond fails at $\lambda$. We also…

Logic · Mathematics 2021-03-12 Shimon Garti , Saharon Shelah

We establish the consistency of the failure of the diamond principle on a cardinal $\kappa$ which satisfies a strong simultaneous reflection property. The result is based on an analysis of Radin forcing, and further leads to a…

Logic · Mathematics 2017-06-06 Omer Ben-Neria

We investigate the generalized tree properties and guessing model properties introduced by Wei\ss\ and Viale, as well as natural weakenings thereof, studying the relationships among these properties and between these properties and other…

Logic · Mathematics 2023-12-12 Chris Lambie-Hanson , Šárka Stejskalová

We prove that the Devlin-Shelah weak diamond implies Galvin's property. On the other hand, Galvin's property is consistent with the negation of the weak diamond, and even with Martin's axiom. We show that the proper forcing axiom implies a…

Logic · Mathematics 2017-02-07 Shimon Garti

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

We investigate the reverse mathematics strength of Martin's pointed tree theorem (MPT) and one of its variants, weak Martin's pointed tree theorem (wMPT).

Logic · Mathematics 2014-04-09 Rupert Hölzl , Frank Stephan , Liang Yu

Under some cardinal arithmetic assumptions, we prove that every stationary subset of lambda of a right cofinality has the weak diamond. This is a strong negation of uniformization. We then deal with a weaker version of the weak diamond-…

Logic · Mathematics 2007-05-23 Saharon Shelah

We isolate \emph{the approximating diamond principles}, which are consequences of the diamond principle at an inaccessible cardinal. We use these principles to find new methods for negating the diamond principle at large cardinals. Most…

Logic · Mathematics 2022-09-13 Omer Ben-Neria , Jing Zhang

We investigate the interaction between compactness principles and guessing principles in the Radin forcing extensions. In particular, we show that in any Radin forcing extension with respect to a measure sequence on $\kappa$, if $\kappa$ is…

Logic · Mathematics 2022-03-01 Omer Ben-Neria , Jing Zhang

We apply set-theoretic methods to study projective modules and their generalizations over transfinite extensions of simple artinian rings R. When R is hereditary and of cardinality at most $2^\omega$, we prove that the Weak Diamond and CH…

Rings and Algebras · Mathematics 2022-03-17 Jan Trlifaj

We obtain bounds on the cardinality of $pcf(\mathfrak{a})$ from instances of weak diamond. Consequently, under mild assumptions there are many singular cardinals of the from $\aleph_\delta$ for which…

Logic · Mathematics 2024-05-07 Shimon Garti

We apply set-theoretic methods to study projective modules and their generalizations over transfinite extensions of simple artinian rings R. We prove that if R is small, then the Weak Diamond implies that projectivity of an arbitrary module…

Rings and Algebras · Mathematics 2022-05-27 Jan Trlifaj

We deal with the combinatorial principle Weak Diamond, showing that we always either a local version is not saturated or we can increase the number of colours. Then we point out a model theoretic consequence of Weak Diamond.

Logic · Mathematics 2021-08-10 Saharon Shelah

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

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 show that compact cardinals and {\rm MM} are sensitive to $\lambda$-closed forcings for arbitrarily large $\lambda$. This is done by adding 'regressive' $\lambda$-Kurepa-trees in either case. We argue that the destruction of regressive…

Logic · Mathematics 2007-05-23 Bernhard Koenig , Yasuo Yoshinobu

I explore two separate topics: the concept of jointness for set-theoretic guessing principles, and the notion of grounded forcing axioms. A family of guessing sequences is said to be joint if all of its members can guess any given family of…

Logic · Mathematics 2017-05-15 Miha E. Habič
‹ Prev 1 2 3 10 Next ›