We generalize recent results by G.A. Freiman, M. Herzog and coauthors on the structure theory of product-sets from the context of linearly (i.e., strictly and totally) ordered groups to linearly ordered semigroups. In particular, we find that if S is a finite subset of a linearly ordered semigroup generating a nonabelian subsemigroup, then |S2| ≥ 3 |S| − 2. On the road to this goal, we also pro...

It is shown how the deformation of the superconformal generators on the string’s worldsheet by a nonabelian super-Wilson line gives rise to a covariant exterior derivative on loop space coming from a nonabelian 2-form on target space. The expression obtained this way is new in the context of strings (but has been considered before in the context of integrable systems), and its consistency is ve...

In this paper, first we introduce the notions of k-nilpotent (solvable) ideals and BCK-algebras. Specially, show that every commutative ideal is 1-nilpotent (solvable). Second, state an equivalent condition to k-nilpotency (solvablity) BCK-algebra. Finally, study n-fold 2-nilpotent BCK-algebras as a generalization BCK-algebras, relation between these two concepts. Basically, compare solvable (B...

Suppose E is a commutative S–algebra, in the sense of Elmendorf, Kriz, Mandell and May [6], and A is a commutative E–algebra. We want to capture the properties and underlying structure of the homotopy groups π∗A = A∗ of A, by studying operations associated to the cohomology theory that E represents. An important family of cohomology operations, called power operations, is constructed via the ex...

A three-fold triple system is a design wherein each pair of treatments occurs exactly once. One way to construct this design is by using an idempotent commutative quasigroup. This paper attempts to provide another method of constructing a 3-fold triple system. Firstly, we would like to discuss compatible factorization without multiple edges using a patterned starter construction. Then, we will ...

We present a candidate supergravity solution for a stacked configuration of stable non-BPS D-branes in Type II string theory compactified on T /Z2. This gives a supergravity description of nonabelian tachyon condensation on the brane worldvolume. BROWN-HET-1263 IC/2001/27

abstract in this presentation, a case of bilateral choroidal folds in patient with diabetic retinopathy was reported. by our knowledge, this case presentation is the first report of choroidal folds in diabetic retinopathy, which bilateral symmetric and horizontal folds arranged in macula. the thick choroid that is developed in diabetics may be a cause of these folds but the source of difference...

In this paper we introduce the notion of $varphi$-commutativity for a Banach algebra $A$, where $varphi$ is a continuous homomorphism on $A$ and study the concept of $varphi$-weak amenability for $varphi$-commutative Banach algebras. We give an example to show that the class of $varphi$-weakly amenable Banach algebras is larger than that of weakly amenable commutative Banach algebras. We charac...

Before we state our main theorems, we begin with some notation: given a finite subset A of some commutative ring, we let A + A denote the set of sums a + b, where a, b ∈ A; and, we let A.A denote the set of products ab, a, b ∈ A. When three or more sums or products are used, we let kA denote the k-fold sumset A+A+ · · ·+A, and let A denote the k-fold product set A.A...A. Lastly, by d ∗ A we mea...