activity
20112022
most citedLayered posets and Kunen's universal collapse

6 citations · 16 across the 19 of their papers we have counts for

collaborators

26 papers

math.LO2022

How robustly can you predict the future?

Sean Cox, Matthew Elpers

Hardin and Taylor \cite{MR2384262} proved that any function on the reals -- even a nowhere continuous one -- can be correctly predicted, based solely on its past behavior, at almos…

math.LO2022

Sparse analytic systems

Brent Cody, Sean Cox, Kayla Lee

Erdős \cite{MR168482} proved that the Continuum Hypothesis (CH) is equivalent to the existence of an uncountable family of (real or complex) analytic functions, such…

math.LO2021

The Diagonal Strong Reflection Principle and its fragments

Sean Cox, Gunter Fuchs

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 r…

math.LO2021

Salce's problem on cotorsion pairs is undecidable

Sean Cox

Salce \cite{MR565595} introduced the notion of a \emph{cotorsion pair} of classes of abelian groups, and asked whether every such pair is \emph{complete} (i.e., has enough injectiv…

math.RT2020

Maximum deconstructibility in module categories

Sean Cox

We prove that Vopěnka's Principle implies that for every class of modules over any ring, the class of \textbf{-Gorenstein Projective modul…

math.LO2020

Forcing axioms and the complexity of non-stationary ideals

Sean Cox, Philipp Lücke

We study the influence of strong forcing axioms on the complexity of the non-stationary ideal on and its restrictions to certain cofinalities. Our main result shows that the…

math.LO2020

Filtration Games and Potentially Projective Modules

Sean D. Cox

The notion of a \textbf{-filtered} object, where is some (typically small) collection of objects in a Grothendieck category, has become ubiq…

math.LO2020

Compactness versus hugeness at successor cardinals

Sean Cox, Monroe Eskew

If is regular and , then the existence of a weakly presaturated ideal on implies . This partially answers a question of Foreman and Magidor ab…

math.LO2020

The Löwenheim-Skolem-Tarski property of Stationary Logic

Sean Cox

Fuchino-Maschio-Sakai~\cite{FuchinoEtAl_DRP_LST} proved that the Löwenheim-Skolem-Tarski (LST) property of Stationary Logic is equivalent to the Diagonal Reflection Principle on in…

math.LO2019

Adjoining only the things you want: a survey of Strong Chang's Conjecture and related topics

Sean Cox

We survey some old and new results on strong variants of Chang's Conjecture and related topics.

math.LO2019

Martin's Maximum and the Diagonal Reflection Principle

Sean Cox, Hiroshi Sakai

We prove that Martin's Maximum does not imply the Diagonal Reflection Principle for stationary subsets of .

math.LO2018

A variant of Shelah's characterization of Strong Chang's Conjecture

Sean Cox, Hiroshi Sakai

Shelah considered a certain version of Strong Chang's Conjecture, which we denote , and proved that it is equivalent to several statements, including the a…

math.LO2018

Club Chang's Conjecture

Sean Cox, Saharon Shelah

Chang's Conjecture (CC) asserts that for every , there exists an that is closed under such that and . By classic results of…

math.LO2018★ 5 cited

Forcing axioms, approachability, and stationary set reflection

Sean D. Cox

We prove a variety of theorems about stationary set reflection and concepts related to internal approachability. We prove that an implication of Fuchino-Usuba relating stationary r…

math.LO2017

On the universality of the nonstationary ideal

Sean Cox

Burke \cite{MR1472122} proved that the generalized nonstationary ideal, denoted NS, is universal in the following sense: every normal ideal, and every tower of normal ideals of ina…

math.LO2016

Strongly proper forcing and some problems of Foreman

Sean Cox, Monroe Eskew

We provide solutions to several problems of Foreman about ideals, several of which are closely related to Mitchell's notion of \emph{strongly proper} forcing. We prove: 1) Presatur…

math.LO2016★ 5 cited

Namba forcing, weak approximation, and guessing

Sean Cox, John Krueger

We prove a variation of Easton's lemma for strongly proper forcings, and use it to prove that, unlike the stronger principle , together with $2^ω\le ω…

math.LO2016

Lower consistency bounds for mutual stationarity with divergent uncountable cofinalities

Dominik Adolf, Sean Cox, Philip Welch

We prove that the upper bounds for the consistency strength of certain instances of mutual stationarity considered by Liu-Shelah~\cite{MR1469093} are close to optimal. We also cons…

math.LO2016

Chang's Conjecture and semiproperness of nonreasonable posets

Sean D. Cox

Let denote the poset which adds a Cohen real then shoots a club through the complement of with countable conditions. We prove that the version o…

math.LO2015

Indestructible Guessing Models and the Continuum

Sean Cox, John Krueger

We introduce a stronger version of an -guessing model, which we call an indestructibly -guessing model. The principle IGMP states that there are stationarily many indestr…

math.LO2015

Characterizing large cardinals in terms of layered posets

Sean Cox, Philipp Lücke

Given an uncountable regular cardinal , a partial order is -stationarily layered if the collection of regular suborders of of cardinality less than is statio…

math.LO2015★ 6 cited

Layered posets and Kunen's universal collapse

Sean D. Cox

We develop the theory of layered posets, and use the notion of layering to prove a new iteration theorem (Theorem 6): if is weakly compact then any universal Kunen iteration of…

math.LO2014

Quotients of Strongly Proper Forcings and Guessing Models

Sean Cox, John Krueger

We prove that a wide class of strongly proper forcing posets have quotients with strong properties. Specifically, we prove that quotients of forcing posets which have simple univer…

math.LO2014

Prevalence of Generic Laver Diamond

Sean D. Cox

Viale \cite{Viale_GuessingModel} introduced the notion of Generic Laver Diamond at ---which we denote ---asserting the existence of a single function f…