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Dowker space Monotonically far coloring number Knaster and friends PFA(S)[S] Forcing Axioms Constructible Universe Mandelbrot set Closed coloring Club Guessing Nonspecial tree Subnormal ideal Cohen real Ascending path Selective Ultrafilter incompactness Ulam matrix Ostaszewski square Well-behaved magma Dushnik-Miller free Boolean algebra Diamond Rado's conjecture full tree strongly bounded groups xbox b-scale Commutative cancellative semigroups Respecting tree positive partition relation countably metacompact Non-saturation specializable Souslin tree polarized partition relation free Souslin tree Filter reflection OCA Coherent tree Was Ulam right? Uniformly homogeneous Weakly compact cardinal Local Club Condensation. Precaliber L-space Reduced Power Absoluteness Successor of Singular Cardinal Fat stationary set Sigma-Prikry Ascent Path Chang's conjecture projective Boolean algebra Chromatic number C-sequence nonmeager set Kurepa Hypothesis HOD very good scale approachability ideal Uniformization sap Subtle tree property Poset AIM forcing regressive Souslin tree ccc Erdos Cardinal Amenable C-sequence Universal Sequences Diamond-sharp O-space Axiom R unbounded function Sakurai's Bell inequality Open Access Souslin Tree Generalized descriptive set theory S-Space Aronszajn tree Forcing Reflecting stationary set square principles weak Kurepa tree Strong coloring Strongly compact cardinal Analytic sets diamond star Hereditarily Lindelöf space perfectly normal Fast club weak square Prevalent singular cardinals P-Ideal Dichotomy middle diamond Hindman's Theorem higher Baire space Martin's Axiom Subtle cardinal Almost countably chromatic Singular cardinals combinatorics Erdos-Hajnal graphs Lipschitz reduction Diamond for trees stationary reflection Entangled linear order Luzin set Knaster Almost Souslin Large Cardinals Ineffable cardinal Iterated forcing Postprocessing function Whitehead Problem ZFC construction Antichain tensor product graph Almost-disjoint family Microscopic Approach Prikry-type forcing 54G20 club_AD SNR Successor of Regular Cardinal super-Souslin tree Vanishing levels reflection principles Subadditive Small forcing Cardinal function Distributive tree Foundations weak diamond Forcing with side conditions PFA Generalized Clubs Jonsson cardinal Uniformly coherent Partition Relations Strongly Luzin set Rock n' Roll Slim tree transformations Minimal Walks square indecomposable filter Parameterized proxy principle Rainbow sets Commutative projection system Greatly Mahlo Countryman line stationary hitting Intersection model Sierpinski's onto mapping principle Singular cofinality Square-Brackets Partition Relations GMA Singular Density Fodor-type reflection Shelah's Strong Hypothesis Interval topology on trees Ramsey theory over partitions Cardinal Invariants stick Hedetniemi's conjecture
Tag Archives: strongly bounded groups
A Shelah group in ZFC
Joint work with Márk Poór. Abstract. In a paper from 1980, Shelah constructed an uncountable group all of whose proper subgroups are countable. Assuming the continuum hypothesis, he constructed an uncountable group $G$ that moreover admits an integer $n$ satisfying … Continue reading
Posted in Groups, Publications
Tagged 03E02, 03E75, 20A15, 20E15, 20F06, Jonsson cardinal, Open Access, Strong coloring, strongly bounded groups, Subadditive, ZFC construction
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