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Related papers: Compactness in singular cardinals revisited

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We prove that successors of singular limits of strongly compact cardinals have the strong tree property. We also prove that aleph_{omega+1} can consistently satisfy the strong tree property.

Logic · Mathematics 2013-01-28 Laura Fontanella

After reviewing various natural bi-interpretations in urelement set theory, including second-order set theories with urelements, we explore the strength of second-order reflection in these contexts. Ultimately, we prove, second-order…

Logic · Mathematics 2024-11-20 Joel David Hamkins , Bokai Yao

We prove the existence and uniqueness of geometric models of local isometry classes of locally homogeneous spaces with sectional curvature $|\operatorname{sec}|\leq 1$. Moreover, we show that the set of geometric models is compact in the…

Differential Geometry · Mathematics 2021-01-19 Francesco Pediconi

This article contains a self-contained proof of the stability under convolution of the space of resurgent functions associated with a closed discrete subset of the complex plane (the set of possible singularities), under the assumption that…

Dynamical Systems · Mathematics 2014-06-27 David Sauzin

If kappa is strongly compact, lambda > kappa is regular, then (2^{< lambda})^+ --> (lambda+eta)^2_theta holds for eta,theta<kappa.

Logic · Mathematics 2007-05-23 Saharon Shelah

The compactness phenomenon is one of the featured aspects of structuralism in mathematics. In simple and broad words, a compactness property holds in a structure if a related property is satisfied by sufficiently many substructures of that…

Logic · Mathematics 2024-08-29 Rahman Mohammadpour

We investigate the statement "the order topology of every countable complete linear order is compact" in the framework of reverse mathematics, and we find that the statement's strength depends on the precise formulation of compactness. If…

Logic · Mathematics 2019-08-01 Paul Shafer

We improve previous work on the consistency strength of mutually stationary sequences of sets concentrating on points with divergent cofinality building on previous work by Adolf, Cox and Welch. Specifically, we have greatly reduced our…

Logic · Mathematics 2019-08-06 Dominik Adolf

Harvey Friedman, in his remarkable paper Finite functions and the necessary use of large cardinals, Ann. Math. 148:803-893, 1998 and in a technical report, Applications of large cardinals to graph theory, Ohio State University, 1997,…

Combinatorics · Mathematics 2019-09-17 S. Gill Williamson

We introduce a covering notion depending on two cardinals, which we call $\mathcal O $-$ [ \mu, \lambda ]$-compactness, and which encompasses both pseudocompactness and many other generalizations of pseudocompactness. For Tychonoff spaces,…

General Topology · Mathematics 2012-11-27 Paolo Lipparini

There is proved the sufficiency of several conditions for the removability of singularities of complex-analytic sets in domains of $\mathbb C^n$.

Complex Variables · Mathematics 2017-10-11 E. M. Chirka

We prove a theorem on structural stability of smooth attractor-repellor endomorphisms of compact manifolds, with singularities. By attractor-repellor, we mean that the non-wandering set of the dynamics $f$ is the disjoint union of a…

Dynamical Systems · Mathematics 2008-09-02 Pierre Berger

A general theorem on fibers of singular sets is presented.

Complex Variables · Mathematics 2013-11-01 Małgorzata Zajęcka

By using Alexander duality on simplicial complexes we give a new and algebraic proof of Dirac's theorem on chordal graphs.

Commutative Algebra · Mathematics 2007-05-23 Jürgen Herzog , Takayuki Hibi , Xinxian Zheng

We prove from suitable large cardinal hypotheses that the least weakly compact cardinal can be unfoldable, weakly measurable and even nearly $\theta$-supercompact, for any desired $\theta$. In addition, we prove several global results…

Logic · Mathematics 2013-05-28 Brent Cody , Moti Gitik , Joel David Hamkins , Jason Schanker

Conditions for Bayesian posterior robustness have been examined in recent literature. However, many of the proofs seem to be long and complicated. In this paper, we first summarize some basic lemmas that have been applied implicitly or…

Statistics Theory · Mathematics 2023-11-06 Yasuyuki Hamura

The purpose of this note is to show that the regular locus of a complex variety is locally parabolic at the singular set. This yields that the regular locus of a compact complex variety, e.g., of a projective variety, is parabolic. We give…

Complex Variables · Mathematics 2015-02-04 Jean Ruppenthal

If T is an iteration tree on K and F is a countably certified extender that coheres with the final model of T, then F is on the extender sequence of the final model of T. Several applications of maximality are proved, including: o K…

Logic · Mathematics 2016-09-07 Ernest Schimmerling , John R. Steel

We investigate negative square-brackets partition relations at successors of singular cardinals of countable cofinality. Along the way we prove some club-guessing results.

Logic · Mathematics 2008-06-03 Todd Eisworth , Saharon Shelah

We prove that there exists a compact two-dimensional polyhedron with the fixed point property and even Euler characteristic. This answers a question posed by R.H. Bing in 1969. We also settle another of Bing's questions.

Algebraic Topology · Mathematics 2017-03-29 Iván Sadofschi Costa