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- Prikry forcing may add a Souslin tree June 12, 2016
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- Prolific Souslin trees March 17, 2016
- Generalizations of Martin’s Axiom and the well-met condition January 11, 2015
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### Keywords

projective Boolean algebra Fodor-type reflection Selective Ultrafilter 20M14 Partition Relations Whitehead Problem Postprocessing function Almost Souslin coloring number Singular coﬁnality Microscopic Approach Kurepa Hypothesis PFA Ostaszewski square Weakly compact cardinal OCA Parameterized proxy principle 05A17 Forcing Axioms ccc Singular cardinals combinatorics Prevalent singular cardinals diamond star PFA(S)[S] Antichain P-Ideal Dichotomy S-Space incompactness Sakurai's Bell inequality square Small forcing HOD Stevo Todorcevic weak square Souslin Tree approachability ideal Luzin set Jonsson cardinal Axiom R Large Cardinals Dushnik-Miller Poset Chang's conjecture Generalized Clubs Erdos-Hajnal graphs very good scale Cardinal Invariants Successor of Singular Cardinal Absoluteness polarized partition relation Cardinal function Ascent Path Forcing Diamond Almost-disjoint famiy Slim tree Club Guessing Distributive tree Non-saturation Rock n' Roll Universal Sequences Rainbow sets Almost countably chromatic square principles Uniformization Rado's conjecture L-space xbox Minimal Walks Shelah's Strong Hypothesis Constructible Universe 11P99 Nonspecial tree Uniformly coherent Square-Brackets Partition Relations tensor product graph Mandelbrot set stationary reflection Successor of Regular Cardinal stationary hitting sap middle diamond Coherent tree Knaster Hedetniemi's conjecture Foundations Aronszajn tree b-scale super-Souslin tree Fat stationary set Reduced Power reflection principles Singular Density Prikry-type forcing Chromatic number Martin's Axiom Cohen real Hindman's Theorem free Boolean algebra Fast club Erdos Cardinal weak diamond Commutative cancellative semigroups Hereditarily Lindelöf space

# Tag Archives: Small forcing

## A cofinality-preserving small forcing may introduce a special Aronszajn tree

Extended Abstract: Shelah proved that Cohen forcing introduces a Souslin tree; Jensen proved that a c.c.c. forcing may consistently add a Kurepa tree; Todorcevic proved that a Knaster poset may already force the Kurepa hypothesis; Irrgang introduced a c.c.c. notion … Continue reading

Posted in Publications, Squares and Diamonds
Tagged 03E04, 03E05, 03E35, Aronszajn tree, Small forcing, Successor of Singular Cardinal, weak square
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