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

# 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 Publications, Topology
Tagged 03E04, 03E65, 54G15, Shelah's Strong Hypothesis
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