Displaying similar documents to “Novikov superalgebras with A 0 = A 1 A 1

Indiscernibles and dimensional compactness

C. Ward Henson, Pavol Zlatoš (1996)

Commentationes Mathematicae Universitatis Carolinae

Similarity:

This is a contribution to the theory of topological vector spaces within the framework of the alternative set theory. Using indiscernibles we will show that every infinite set u S G in a biequivalence vector space W , M , G , such that x - y M for distinct x , y u , contains an infinite independent subset. Consequently, a class X G is dimensionally compact iff the π -equivalence M is compact on X . This solves a problem from the paper [NPZ 1992] by J. Náter, P. Pulmann and the second author.

Ultrafilter-limit points in metric dynamical systems

Salvador García-Ferreira, Manuel Sanchis (2007)

Commentationes Mathematicae Universitatis Carolinae

Similarity:

Given a free ultrafilter p on and a space X , we say that x X is the p -limit point of a sequence ( x n ) n in X (in symbols, x = p - lim n x n ) if for every neighborhood V of x , { n : x n V } p . By using p -limit points from a suitable metric space, we characterize the selective ultrafilters on and the P -points of * = β ( ) . In this paper, we only consider dynamical systems ( X , f ) , where X is a compact metric space. For a free ultrafilter p on * , the function f p : X X is defined by f p ( x ) = p - lim n f n ( x ) for each x X . These functions are not continuous in general....

The cubic Szegő equation

Patrick Gérard, Sandrine Grellier (2010)

Annales scientifiques de l'École Normale Supérieure

Similarity:

We consider the following Hamiltonian equation on the L 2 Hardy space on the circle, i t u = Π ( | u | 2 u ) , where Π is the Szegő projector. This equation can be seen as a toy model for totally non dispersive evolution equations. We display a Lax pair structure for this equation. We prove that it admits an infinite sequence of conservation laws in involution, and that it can be approximated by a sequence of finite dimensional completely integrable Hamiltonian systems. We establish several...

Problems remaining NP-complete for sparse or dense graphs

Ingo Schiermeyer (1995)

Discussiones Mathematicae Graph Theory

Similarity:

For each fixed pair α,c > 0 let INDEPENDENT SET ( m c n α ) and INDEPENDENT SET ( m ( ) - c n α ) be the problem INDEPENDENT SET restricted to graphs on n vertices with m c n α or m ( ) - c n α edges, respectively. Analogously, HAMILTONIAN CIRCUIT ( m n + c n α ) and HAMILTONIAN PATH ( m n + c n α ) are the problems HAMILTONIAN CIRCUIT and HAMILTONIAN PATH restricted to graphs with m n + c n α edges. For each ϵ > 0 let HAMILTONIAN CIRCUIT (m ≥ (1 - ϵ)(ⁿ₂)) and HAMILTONIAN PATH (m ≥ (1 - ϵ)(ⁿ₂)) be the problems HAMILTONIAN CIRCUIT and HAMILTONIAN PATH...

Hamiltonian-colored powers of strong digraphs

Garry Johns, Ryan Jones, Kyle Kolasinski, Ping Zhang (2012)

Discussiones Mathematicae Graph Theory

Similarity:

For a strong oriented graph D of order n and diameter d and an integer k with 1 ≤ k ≤ d, the kth power D k of D is that digraph having vertex set V(D) with the property that (u, v) is an arc of D k if the directed distance d D ( u , v ) from u to v in D is at most k. For every strong digraph D of order n ≥ 2 and every integer k ≥ ⌈n/2⌉, the digraph D k is Hamiltonian and the lower bound ⌈n/2⌉ is sharp. The digraph D k is distance-colored if each arc (u, v) of D k is assigned the color i where i = d D ( u , v ) . The digraph...

Distributivity of strong implications over conjunctive and disjunctive uninorms

Daniel Ruiz-Aguilera, Joan Torrens (2006)

Kybernetika

Similarity:

This paper deals with implications defined from disjunctive uninorms U by the expression I ( x , y ) = U ( N ( x ) , y ) where N is a strong negation. The main goal is to solve the functional equation derived from the distributivity condition of these implications over conjunctive and disjunctive uninorms. Special cases are considered when the conjunctive and disjunctive uninorm are a t -norm or a t -conorm respectively. The obtained results show a lot of new solutions generalyzing those obtained in previous works...