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- The S-space problem, and the cardinal invariant $\mathfrak b$ April 4, 2013
- An $S$-space from a Cohen real April 3, 2013
- Forcing with a Souslin tree makes $\mathfrak p=\omega_1$ April 1, 2013
- The S-space problem, and the cardinal invariant $\mathfrak p$ March 28, 2013
- Jones’ theorem on the cardinal invariant $\mathfrak p$ March 26, 2013
- Erdős 100 March 26, 2013
- Bell’s theorem on the cardinal invariant $\mathfrak p$ March 21, 2013
- The $\Delta$-system lemma: an elementary proof March 20, 2013
Keywords
Knaster Shelah's Strong Hypothesis Partition Relations Cohen real b-scale Singular cardinals combinatorics Mandelbrot set Successor of Regular Cardinal Singular Density Aronszajn tree very good scale reflection principles Cardinal function Rock n' Roll Chromatic number Singular Cofinality Minimal Walks Uniformization weak diamond Poset Small forcing Dushnik-Miller stationary hitting Axiom R diamond star Souslin Tree stationary reflection approachability ideal Almost countably chromatic incompactness Erdos Cardinal Diamond Rado's conjecture polarized partition relation Large Cardinals weak square Ostaszewski square Successor of Singular Cardinal Hereditarily Lindelöf space Generalized Clubs Square-Brackets Partition Relations Erdos-Hajnal graphs Prikry-type forcing P-Ideal Dichotomy Prevalent singular cardinals Kurepa Hypothesis Foundations Club Guessing projective Boolean algebra square Non-saturation free Boolean algebra Forcing PFA(S)[S] Sakurai's Bell inequality Whitehead Problem Antichain S-Space sap Rainbow sets middle diamond
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
