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Partition Relations Uniformly coherent Reflecting stationary set free Boolean algebra Ulam matrix PFA 54G20 Knaster and friends Coherent tree PFA(S)[S] Successor of Regular Cardinal Rock n' Roll Diamond for trees Reduced Power weak diamond specializable Souslin tree Forcing Fast club positive partition relation Amenable C-sequence Subtle tree property sap P-Ideal Dichotomy Mandelbrot set unbounded function S-Space Whitehead Problem Rado's conjecture Sakurai's Bell inequality Rainbow sets Hindman's Theorem Diamond-sharp GMA Dushnik-Miller Forcing Axioms diamond star Iterated forcing Generalized descriptive set theory Prikry-type forcing Cardinal Invariants Singular cardinals combinatorics b-scale Foundations square principles Weakly compact cardinal Fat stationary set Strong coloring Shelah's Strong Hypothesis Lipschitz reduction Square-Brackets Partition Relations Constructible Universe Well-behaved magma strongly bounded groups Knaster Almost Souslin Jonsson cardinal Ostaszewski square projective Boolean algebra Nonspecial tree Distributive tree O-space Universal Sequences Almost-disjoint family Sierpinski's onto mapping principle Small forcing stationary hitting stationary reflection Vanishing levels higher Baire space Absoluteness OCA Non-saturation square Parameterized proxy principle Almost countably chromatic Kurepa Hypothesis polarized partition relation Cohen real tensor product graph Cardinal function free Souslin tree Successor of Singular Cardinal Martin's Axiom middle diamond Erdos Cardinal transformations incompactness Luzin set Was Ulam right Analytic sets Postprocessing function SNR Filter reflection Strongly Luzin set Hedetniemi's conjecture Selective Ultrafilter Chromatic number coloring number club_AD Sigma-Prikry Club Guessing Uniformly homogeneous reflection principles Slim tree Diamond countably metacompact Ascent Path ZFC construction Local Club Condensation. Generalized Clubs Subtle cardinal Aronszajn tree Antichain approachability ideal stick Prevalent singular cardinals Erdos-Hajnal graphs indecomposable ultrafilter Axiom R Uniformization C-sequence xbox Hereditarily Lindelöf space Commutative cancellative semigroups Fodor-type reflection Subadditive nonmeager set Open Access AIM forcing super-Souslin tree Singular cofinality Precaliber Souslin Tree Microscopic Approach weak square L-space Chang's conjecture Large Cardinals Poset ccc Ramsey theory over partitions full tree Dowker space HOD Closed coloring very good scale Ineffable cardinal Minimal Walks weak Kurepa tree Greatly Mahlo Singular Density Subnormal ideal regressive Souslin tree
Tag Archives: Hereditarily Lindelöf space
The S-space problem, and the cardinal invariant $\mathfrak p$
Recall that an $S$-space is a regular hereditarily separable topological space which is not hereditarily Lindelöf. Do they exist? Consistently, yes. However, Szentmiklóssy proved that compact $S$-spaces do not exist, assuming Martin’s Axiom. Pushing this further, Todorcevic later proved that … Continue reading
Posted in Blog, Expository, Open Problems
Tagged Hereditarily Lindelöf space, P-Ideal Dichotomy, PFA(S)[S], S-Space
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On topological spaces of singular density and minimal weight
Abstract: We introduce a weakening of the Generalized Continuum Hypothesis, which we will refer to as the Prevalent Singular cardinals Hypothesis (PSH), and show it implies that every topological space of density and weight $\aleph_{\omega_1}$ is not hereditarily Lindelöf. The assumption … Continue reading
Workshop on Set Theory and its Applications, February 2007
These are the slides of a talk given at the Workshop on Set Theory and its Applications workshop (Weizmann Institute, February 19, 2007). Talk Title: Nets of spaces having singular density Abstract: The weight of a topological space X is the … Continue reading
Infinite Combinatorial Topology
Back in 2005, as a master student, I attended a course by Boaz Tsaban, entitled “Infinite Combinatorial Topology”. A friend and I decided to produce lecture notes, but in a somewhat loose sense, that is: we sometimes omit material given … Continue reading
Posted in Notes
Tagged b-scale, Cardinal function, Cardinal Invariants, Hereditarily Lindelöf space
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