Abstract In the late 1940s and early 1950s, Lorenzen developed his operative logic mathematics, a form of constructive mathematics. Nowadays this is mostly seen as precursor better-known dialogical (Notable exceptions are works Schroeder-Heister 2008; Coquand Neuwirth 2017; Kahle Oitavem 2020.), one might assume that same philosophical motivations were present in both works. However, we want to...

In diflerential geometry curves are characterized as mappings from an interval to the plane. In topology curves are chamcterized as a Hausdorfl space with certain countability properties. Neither of these definitions captures the role that curves play in vision, however, in which curves can denote simple objects (such as a straight line), or complicated objects (such as a jumble of string). The...

It is known that for Ω a connected separable metric space, a function Ω → R which at every point attains a weak local extremummust have countable image. Let Ω ⊂ R be a bounded domain and f : Ω → C a measurable, bounded, quasi-continuous function. For n ∈ Z+, we show that if |f | has countable image then f attains weak local extremum at each point of a dense open subset. We show by examples the ...

Let X be a compact Hausdorff space. We denote by C(X) the multiplicative semigroup of all continuous real-valued functions on X. Milgram [2] has shown that C(X) as a semigroup determines X. In this paper we investigate the set %(X) of all continuous positive nontrivial2 multiplicative functionals on C(X), where C(X) has the topology of uniform convergence. If multiplication is defined pointwise...

About the Course In this course we shall mostly talk and think about numbers, working carefully from definitions. The course will have the following components: 1. Proof and Mathematical Argument 2. Sets, Relations and Functions 3. Construction and Properties of Number Systems 4. Some Number Theory 5. Countability If you wish to read further about various topics covered in this course and relat...

2.1. Basic properties: separation, countability, separability, compactness, connectedness. A space X is Tychonoff if for u, v ∈ X, there exists a neighborhood of u not containing v (and by symmetry a neighborhood of v not containing u). It is Hausdorff if every two points can be separated by disjoint neighborhoods. It is regular if it is Tychonoff and every closed set and point not in the set c...

For a rational tower, i.e., a composition sequence of rational maps, in addition to the algebraic and dynamical exceptional sets, various Nevanlinna theoretical exceptional sets are defined, and as we showed previously in the case of iterations, all of them are the same. In this paper, we extend this result to the cases of a rational tower with summable distortions and a finitely generated rati...

In this paper, we consider a generalized large game model where the agent space is divided into countable subgroups and each player’s payoff depends on her own action and the action distribution in each of the subgroups. Given the countability assumption on its action or payoff space or the Loeb assumption on its agent space, we show that that a given distribution is an equilibrium distribution...

Let P be a property (or, equivalently, a class) of topological spaces. A space X is called P-bounded if every subspace of X with (or in) P has compact closure. Thus, countable-bounded has been known as ω-bounded and (σ-compact)-bounded as strongly ω-bounded. In this paper we present a systematic study of the interrelations of these two known “boundedness” concepts with P-boundedness where P is ...

1. It has been shown by Radó3 that every Riemann surface satisfies Hausdorff's second countability axiom. In the same paper Radó gives a construction due to Prüfer of a real 2-dimensional locally Euclidean space whose open sets do not have a countable base. The purpose of this paper is to confirm a conjecture of Bochner that there exist non second-countable complex manifolds of complex dimensio...