Transitive matrices, strict preference and intensity operators

Let X be a set of alternatives and a_{ij} a positive number expressing how much the alternative x_{i} is preferred to the alternative x_{j}. Under suitable hypothesis of no indifference and transitivity over the pairwise comparison matrix A= (a_{ij}), the alternatives can be ordered as a chain . Then a coherent priority vector is a vector giving a weighted ranking agreeing with the obtained chain and an intensity vector is a coherent priority vector encoding information about the intensities of the preferences. In the paper we look for operators F that, acting on the row vectors translate the matrix A in an intensity vector

Supertubes in Matrix model and DBI action

We show the equivalence between the supertube solutions with an arbitrary cross section in two different actions, the DBI action for the D2-brane and the matrix model action for the D0-branes. More precisely, the equivalence between the supertubes in the D2-brane picture and the D0-brane picture is shown in the boundary state formalism which is valid for all order in \alpha'. This is an application of the method using the infinitely many D0-branes and anti-D0-branes which was used to show other equivalence relations between two seemingly different D-brane systems, including the D-brane realization of the ADHM construction of instanton. We also apply this method to the superfunnel type solutions successfully.Comment: 24 pages, references added, version to appear in JHE

The Non-Abelian Self-Dual String and the (2,0)-Theory

We argue that the relevant higher gauge group for the non-abelian generalization of the self-dual string equation is the string 2-group. We then derive the corresponding equations of motion and discuss their properties. The underlying geometric picture is a string structure, i.e. a categorified principal bundle with connection whose structure 2-group is the string 2-group. We readily write down the explicit elementary solution to our equations, which is the categorified analogue of the 't Hooft-Polyakov monopole. Our solution passes all the relevant consistency checks; in particular, it is globally defined on $\mathbb{R}^4$ and approaches the abelian self-dual string of charge one at infinity. We note that our equations also arise as the BPS equations in a recently proposed six-dimensional superconformal field theory and we show that with our choice of higher gauge structure, the action of this theory can be reduced to four-dimensional supersymmetric Yang-Mills theory.Comment: v3: 1+42 pages, presentation improved, typos fixed, published versio