The signature of the Poincaré duality of compact topological manifolds with local system of coefficients can be described as a natural invariant of nondegenerate symmetric quadratic forms defined on a category of infinite dimensional linear spaces. The objects of this category are linear spaces of the form W = V ⊕ V ∗ where V is abstarct linear space with countable base. The space W is consider...

We introduce the category IVRel(H) consisting of interval-valued H-fuzzy relational spaces and relation preserving mappings between them and we study structures of the category IVRel(H) in the viewpoint of the topological universe introduced by Nel. Thus we show that IVRel(H) satisfies all the conditions of a topological universe over Set except the terminal separator property and IVRel(H) is C...

Higher-dimensional automata constitute a very expressive model for concurrent systems. In this paper, we discuss " topological abstraction " of higher-dimensional automata, i.e., the replacement of HDAs by smaller ones that can be considered equivalent from both a computer scientific and a topo-logical point of view. By definition, topological abstraction preserves the ho-motopy type, the trace...

A topological property is properly hereditary property if whenever every proper subspace has the property, the whole space has the property. In this note, we will study some topological properties that are preserved by proper subspaces; in fact, we will study the following topological properties: Baire spaces, second category, sequentially compact, hemicompact, δ-normal, and spaces having dispe...

As application of complete metric space, we proved a Baire’s category theorem. Then we defined some spaces generated from real normed space and discussed each of them. In the second section, we showed the equivalence of convergence and the continuity of a function. In other sections, we showed some topological properties of two spaces, which are topological space and linear topological space ge...

A precise concept of concrete geometrical category is introduced in an axiomatic way. To any algebra L for an many-sorted infinitary algebraic theory T is associated a concrete geometrical category Geo(L), the so-called classifying concrete geometrical category of L, satisfying a universal property. The terminology "geometrical" is justified firstly for Geo(L) and secondly for any concrete geom...

Ideas from the theory of topological stability of smooth maps are transported into the controlled topological category. For example, the controlled topological equivalence of maps is discussed. These notions are related to the classi cation of manifold approximate brations and manifold strati ed approximate brations. In turn, these maps form a bundle theory which can be used to describe neighbo...

Let ∆∞ = End([∞]) be the monoid of convergent monotonic sequences in N∪{∞}. The category Pre(∆∞) of sequential sets is the category whose objects are sets equipped with an action of this monoid, and whose morphisms are equivariant maps. We call a category C sequentially generated if it is a localization of Pre(∆∞). In this paper we show that several important categories, including the category ...

A theory of topological gravity is a homotopy-theoretic representation of the Segal-Tillmann topologification of a two-category with cobordisms as morphisms. This note describes a relatively accessible example of such a thing, suggested by the wall-crossing formulas of Donaldson theory. 1. Gravity categories A cobordism category has manifolds as objects, and cobordisms as morphisms. Such catego...

Introduction. Some years ago Hausdorff, using Hamel bases, showed that any infinite dimensional real Banach space contained a second category linear subspace that was not complete under any equivalent norm [5]. It is shown below that a slight abstraction of his construction leads to the following: (A) a "multiple offender" example (Theorem 3), one that combines several pathological features whi...