Search results for "rete"

Existence of Unconditional Bases in Spaces of Polynomials and Holomorphic Functions

2002

Our main result shows that every Montel Kothe echelon or coechelon space E of order 1 < p ≤ ∞ is nuclear if and only if for every (some) m ≥ 2 the space ((mE), τ0) of m-homegeneus polynomials on E endowed with the compact-open topology τ0 has an unconditional basis if and only if the space (ℋ(E), τδ) of holomorphic functions on E endowed with the bornological topology τδ associated to τ0 has an unconditional basis (for coechelon spaces τδ equals τ0). The main idea is to extend the concept of the Gordon-Lewis property from Banach to Frechet and (DF) spaces. In this way we obtain techniques which are used to characterize the existence of unconditional basis in spaces of m-th (symmetric) tenso…

Contractivity results in ordered spaces. Applications to relative operator bounds and projections with norm one

2016

This paper provides various “contractivity” results for linear operators of the form I−C where C are positive contractions on real ordered Banach spaces X. If A generates a positive contraction semigroup in Lebesgue spaces Lp(μ), we show (M. Pierre's result) that A(λ−A)−1 is a “contraction on the positive cone”, i.e. A(λ−A)−1x≤x for all x∈L+p(μ)(λ>0), provided that p⩾2.  We show also that this result is not true for 1 ⩽ p<2. We give an extension of M. Pierre's result to general ordered Banach spaces X under a suitable uniform monotony assumption on the duality map on the positive cone X+. We deduce from this result that, in such spaces, I−C is a contraction on X+ for any positive projection…

Projective spaces on partially ordered sets and Desargues' postulate

1991

We introduce a generalized concept of projective and Desarguean space where points (and lines) may be of different size. Every unitary module yields an example when we take the 1-and 2-generated submodules as points and lines. In this paper we develop a method of constructing a wide range of projective and Desarguean spaces by means of lattices.

A unified approach to projective lattice geometries

1992

The interest in pursuing projective geometry on modules has led to several lattice theoretic generalizations of the classical synthetic concept of projective geometry on vector spaces.

Two integrals and some modified versions — Critical remarks

1986

The aim of this paper is to discuss different constructions of integrals (Sections 3 and 4) based on @?-decomposable measures (Section 1). According to the classification of the continuous t-conorms @? in essentially two types namely v and Archimedean t-conorms, there exist mainly two types of integrals namely the constructions of Sugeno (Section 3) and of Weber (Section 4). Further constructions corresponding to the Archimedean case result to be special cases or not well defined (Section 4). In all cases a crucial property is some restricted distribution law for the pair (@?, ) with an appropriate operation(Section 2). Some applications shall illustrate the use of the two integrals (Sectio…

A candidate for a noncompact quantum group

1996

A previous letter (Bidegain, F. and Pinczon, G:Lett. Math. Phys.33 (1995), 231–240) established that the star-product approach of a quantum group introduced by Bonneau et al. can be extended to a connected locally compact semisimple real Lie group. The aim of the present Letter is to give an example of what a noncompact quantum group could be. From half of the discrete series ofSL(2,\(\mathbb{R}\)), a new type of quantum group is explicitly constructed.

On the Range of Two Convolution Operators

2000

Embedding Locally Projective Planar Spaces Into Projective Spaces

1988

We shall show that a 3-dimensional locally projective planar space of finite order n can be embedded into a 3-dimensional projective space of order n, if it has at least n 3 points.

Embedding linear spaces with two line degrees in finite projective planes

1986

In this paper we shall classify all finite linear spaces with line degrees n and n-k having at most n2+n+1 lines. As a consequence of this classification it follows: If n is large compared with k, then any such linear space can be embedded in a projective plane of order n−1 or n.

Polynomial Identities and Asymptotic Methods

2005

Polynomial identities and PI-algebras $S_n$-representations Group gradings and group actions Codimension and colength growth Matrix invariants and central polynomials The PI-exponent of an algebra Polynomial growth and low PI-exponent Classifying minimal varieties Computing the exponent of a polynomial $G$-identities and $G\wr S_n$-action Superalgebras, *-algebras and codimension growth Lie algebras and nonassociative algebras The generalized-six-square theorem Bibliography Index.