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It is a well-known result in pointfree topology that every locally compact frame is spatial. Whether this result extends to MT-algebras (McKinsey-Tarski algebras) was an open problem. We resolve it in the negative by constructing a locally…

General Topology · Mathematics 2025-08-05 G. Bezhanishvili , S. D. Melzer , R. Raviprakash , A. L. Suarez

This paper investigates instances of Sobolev embeddings characterized by local compactness at every point within their domain, except for a single point. We obtain the sharp conditions that distinguish compactness from non-compactness and…

Functional Analysis · Mathematics 2024-09-17 Chian Yeong Chuah , Jan Lang

One shows for Banach bundles in a certain class that having a second countable locally compact Hausdorff base space and separable fibers implies the separability of the Banach space of the all sections that vanish at infinity. In the…

Functional Analysis · Mathematics 2018-02-07 Aldo J. Lazar

We show that, contrary to the commonly held view, there is a natural and optimal compactness theorem for $\mathrm{L}_{\infty\infty}$ which generalizes the usual compactness theorem for first order logic. The key to this result is the switch…

Logic · Mathematics 2025-07-29 Juan M Santiago Suárez , Matteo Viale

We define a class of subsets of a topological space that coincides with the class of compact saturated subsets when the space is sober, and with enough good properties when the space is not sober. This class is introduced especially in view…

General Topology · Mathematics 2011-06-21 Paul Poncet

In this note we give a simple proof that every subspace of L_p, 2<p<infinity, with an unconditional basis has an equivalent norm determined by partitions and weights. Consequently L_p has a norm determined by partitions and weights.

Functional Analysis · Mathematics 2007-05-23 Dale Alspach , Simei Tong

We characterize the finite dimensional asymmetric normed spaces which are right bounded and the relation of this property with the natural compactness properties of the unit ball, as compactness and strong compactness. In contrast with some…

General Topology · Mathematics 2017-02-15 Natalia Jonard-Pérez , Enrique A. Sánchez-Pérez

We characterize ultrafilter convergence and ultrafilter compactness in linearly ordered and generalized ordered topological spaces. In such spaces, and for every ultrafilter $D$, the notions of $D$-compactness and of $D$-pseudocompactness…

General Topology · Mathematics 2016-08-30 Paolo Lipparini

This note provides a correct proof of the result claimed by the second author that locally compact normal spaces are collectionwise Hausdorff in certain models obtained by forcing with a coherent Souslin tree. A novel feature of the proof…

General Topology · Mathematics 2019-08-15 Alan Dow , Franklin D. Tall

We reconsider the issue of proving large scale spatial homogeneity of the universe, given isotropic observations about us and the possibility of source evolution both in numbers and luminosities. Two theorems make precise the freedom…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Nazeem Mustapha , Charles Hellaby , G. F. R. Ellis

The notion of soft sets is introduced as a general mathematical tool for dealing with uncertainty. In this paper, we consider the concepts of soft compactness, countably soft compactness and obtain some results. We study some soft…

General Mathematics · Mathematics 2014-01-28 E. Peyghan , B. Samadi , A. Tayebi

Let B(kappa, lambda) be the subalgebra of P(kappa) generated by [kappa]^{<= lambda}. It is shown that if B is any homomorphic image of B(kappa, lambda) then either |B|< 2^lambda or |B|=|B|^lambda, moreover if X is the Stone space of B then…

Logic · Mathematics 2009-09-25 Istvan Juhász , Saharon Shelah

We give an elementary proof of a compact embedding theorem in abstract Sobolev spaces. The result is first presented in a general context and later specialized to the case of degenerate Sobolev spaces defined with respect to nonnegative…

Analysis of PDEs · Mathematics 2011-11-01 Seng-Kee Chua , Scott Rodney , Richard L. Wheeden

In this article we introduce a new scale of weighted Orlicz-Sobolev sequence spaces generated by a class of suitable Orlicz functions and prove various continuity and compactness criteria for them. In a nutshell, continuity is a consequence…

Functional Analysis · Mathematics 2025-03-26 Pierre-A. Vuillermot

The idea of convex sets and various related results in 2-Probabilistic normed spaces were established in [HR]. In this paper, We obtain the concepts of convex series closedness, convex series compactness, boundedness and their…

Functional Analysis · Mathematics 2017-08-04 P. K. Harikrishnan , Bernardo Lafuerza Guillen , K. T. Ravindran

We show that the Gromov-Hausdorff limit of a sequence of leaves in a compact foliation is a covering space of the limiting leaf which is no larger than this leaf's holonomy cover. We also show that convergence to such a limit is smooth…

Differential Geometry · Mathematics 2013-04-24 Pablo Lessa

In a countably normed space which is a linear space equipped with a countable number of pair-wise compatible norms, we prove the existence of a common nearest point (in all norms) from a point outside a nonempty subset if this subset is…

Functional Analysis · Mathematics 2022-12-14 Moustafa M. Zakaria , Nashat Faried , Hany A. El-Sharkawy

All spaces are assumed to be separable and metrizable. We show that, assuming the Axiom of Determinacy, every zero-dimensional homogeneous space is strongly homogeneous (that is, all its non-empty clopen subspaces are homeomorphic), with…

General Topology · Mathematics 2020-03-03 Raphaël Carroy , Andrea Medini , Sandra Müller

We study the presence of lumplike solutions in models described by a single real scalar field with standard kinematics in two-dimensional spacetime. The results show several distinct models that support the presence of bell-shaped, lumplike…

High Energy Physics - Theory · Physics 2015-10-07 D. Bazeia , M. A. Marques , R. Menezes

A dual pair formulation for asymmetric locally convex spaces is developed that strictly generalises the ordinary vector space setting. The concept of a polar topology carries over to the asymmetric case and some familiar results are…

General Topology · Mathematics 2026-02-24 Jobst Ziebell