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Prikry-type forcing Knaster Coherent tree Selective Ultrafilter b-scale Forcing Foundations Uniformization Fast club Non-saturation xbox L-space polarized partition relation Dushnik-Miller Parameterized proxy principle PFA(S)[S] Hereditarily Lindelöf space Antichain Rainbow sets square Club Guessing OCA Cardinal function Almost Souslin Singular coﬁnality P-Ideal Dichotomy Jonsson cardinal Hedetniemi's conjecture Almost-disjoint famiy stationary hitting Microscopic Approach Forcing Axioms 05A17 Diamond stationary reflection Constructible Universe Weakly compact cardinal projective Boolean algebra free Boolean algebra Fodor-type reflection Rado's conjecture Large Cardinals Almost countably chromatic incompactness ccc 20M14 Whitehead Problem Rock n' Roll very good scale Prevalent singular cardinals middle diamond Successor of Singular Cardinal sap Stevo Todorcevic weak square approachability ideal Slim tree Aronszajn tree Shelah's Strong Hypothesis weak diamond tensor product graph PFA Poset Axiom R Successor of Regular Cardinal Souslin Tree 11P99 Minimal Walks Sakurai's Bell inequality Hindman's Theorem Fat stationary set Martin's Axiom Partition Relations Singular Density Kurepa Hypothesis Singular Cofinality S-Space Universal Sequences Mandelbrot set Generalized Clubs Erdos Cardinal Absoluteness Small forcing Reduced Power Singular cardinals combinatorics diamond star 05D10 Chromatic number Erdos-Hajnal graphs coloring number Square-Brackets Partition Relations Cohen real Cardinal Invariants Chang's conjecture reflection principles Ostaszewski square Ascent Path HOD Commutative cancellative semigroups

# Tag Archives: 54G15

## A topological reflection principle equivalent to Shelah’s strong hypothesis

Abstract: We notice that Shelah’s Strong Hypothesis (SSH) is equivalent to the following reflection principle: Suppose $\mathbb X$ is an (infinite) first-countable space whose density is a regular cardinal, $\kappa$. If every separable subspace of $\mathbb X$ is of cardinality at most … Continue reading

Posted in Compactness, Publications, Topology
Tagged 03E04, 03E65, 54G15, Shelah's Strong Hypothesis
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