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- A strong form of König’s lemma October 21, 2017
- Prikry forcing may add a Souslin tree June 12, 2016
- The reflection principle $R_2$ May 20, 2016
- Prolific Souslin trees March 17, 2016
- Generalizations of Martin’s Axiom and the well-met condition January 11, 2015
- Many diamonds from just one January 6, 2015
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Ostaszewski square Successor of Regular Cardinal Square-Brackets Partition Relations Nonspecial tree 20M14 Diamond square principles Large Cardinals Singular cardinals combinatorics reflection principles diamond star stationary reflection 05A17 Chromatic number Coherent tree Prikry-type forcing Non-saturation incompactness Foundations Hedetniemi's conjecture middle diamond Distributive tree Mandelbrot set Absoluteness Knaster Uniformization Aronszajn tree Luzin set coloring number ccc Weakly compact cardinal Almost Souslin Stevo Todorcevic Universal Sequences approachability ideal Sakurai's Bell inequality Jonsson cardinal Singular coﬁnality Kurepa Hypothesis Hindman's Theorem Rainbow sets Selective Ultrafilter Uniformly coherent projective Boolean algebra Martin's Axiom Minimal Walks Commutative cancellative semigroups P-Ideal Dichotomy Almost-disjoint famiy sap Rado's conjecture Fast club Forcing Axioms Erdos-Hajnal graphs Rock n' Roll Cohen real very good scale Erdos Cardinal PFA(S)[S] Parameterized proxy principle polarized partition relation Hereditarily Lindelöf space square Partition Relations Reduced Power Postprocessing function Souslin Tree 11P99 PFA Successor of Singular Cardinal OCA S-Space Dushnik-Miller super-Souslin tree Axiom R Poset stationary hitting Forcing Chang's conjecture xbox Fodor-type reflection free Boolean algebra HOD Shelah's Strong Hypothesis Antichain Club Guessing Almost countably chromatic Slim tree Singular Density tensor product graph weak diamond weak square b-scale Generalized Clubs Prevalent singular cardinals Cardinal Invariants Ascent Path L-space Whitehead Problem Fat stationary set Constructible Universe Small forcing Microscopic Approach Cardinal function

# Tag Archives: L-space

## Syndetic colorings with applications to S and L

Notation. Write $\mathcal Q(A):=\{ a\subseteq A\mid a\text{ is finite}, a\neq\emptyset\}$. Definition. An L-space is a regular hereditarily Lindelöf topological space which is not hereditarily separable. Definition. We say that a coloring $c:[\omega_1]^2\rightarrow\omega$ is L-syndetic if the following holds. For every uncountable … Continue reading