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Chang's conjecture Antichain positive partition relation Weakly compact cardinal Coherent tree Precaliber Fat stationary set Cohen real L-space Was Ulam right? regressive Souslin tree Constructible Universe S-Space approachability ideal Aronszajn tree Fodor-type reflection Open Access Almost-disjoint family Generalized Clubs polarized partition relation OCA super-Souslin tree square Amenable C-sequence Hereditarily Lindelöf space Diamond Ineffable cardinal Parameterized proxy principle Souslin Tree Hedetniemi's conjecture higher Baire space weak diamond unbounded function Singular cofinality Uniformly homogeneous Well-behaved magma Slim tree projective Boolean algebra Selective Ultrafilter weak Kurepa tree stationary hitting Singular cardinals combinatorics HOD incompactness Absoluteness nonmeager set specializable Souslin tree Microscopic Approach Poset countably metacompact Successor of Regular Cardinal Generalized descriptive set theory Reduced Power sap indecomposable ultrafilter Ulam matrix diamond star Local Club Condensation. Uniformization Prevalent singular cardinals Singular Density Erdos-Hajnal graphs PFA(S)[S] Kurepa Hypothesis Rainbow sets Strongly compact cardinal Cardinal function Club Guessing Cardinal Invariants transformations Analytic sets Ostaszewski square Filter reflection Subnormal ideal Closed coloring Commutative projection system Lipschitz reduction Chromatic number Shelah's Strong Hypothesis Martin's Axiom Greatly Mahlo Fast club very good scale club_AD middle diamond SNR Erdos Cardinal Knaster and friends Distributive tree Minimal Walks Vanishing levels Hindman's Theorem Commutative cancellative semigroups Dowker space Uniformly coherent Ramsey theory over partitions Sakurai's Bell inequality Foundations Nonspecial tree Subtle cardinal 54G20 stationary reflection Partition Relations Luzin set reflection principles Ascent Path square principles Small forcing tensor product graph Postprocessing function stick Whitehead Problem Countryman line GMA ZFC construction weak square Knaster full tree Diamond for trees Dushnik-Miller free Boolean algebra Universal Sequences Axiom R Forcing PFA Rock n' Roll Respecting tree Reflecting stationary set Almost countably chromatic Subadditive Subtle tree property Prikry-type forcing Sigma-Prikry Large Cardinals Almost Souslin xbox free Souslin tree Intersection model Strongly Luzin set Square-Brackets Partition Relations Jonsson cardinal ccc coloring number Mandelbrot set strongly bounded groups Diamond-sharp O-space Sierpinski's onto mapping principle C-sequence Successor of Singular Cardinal b-scale Iterated forcing AIM forcing Non-saturation Rado's conjecture Forcing Axioms P-Ideal Dichotomy Strong coloring
Tag Archives: Amenable C-sequence
Winter School in Abstract Analysis, January 2023
I gave a 3-lecture tutorial at the Winter School in Abstract Analysis in Steken, January 2023. Title: Club guessing Abstract. Club guessing principles were introduced by Shelah as a weakening of Jensen’s diamond. Most spectacularly, they were used to prove … Continue reading
Was Ulam right? I: Basic theory and subnormal ideals
Joint work with Tanmay Inamdar. Abstract. We introduce various coloring principles which generalize the so-called onto mapping principle of Sierpinski to larger cardinals and general ideals. We prove that these principles capture the notion of an Ulam matrix and allow … Continue reading
Distributive Aronszajn trees
Joint work with Ari Meir Brodsky. Abstract. Ben-David and Shelah proved that if
