Some Consequences of Noncommutative Worldsheet of Superstring

In this paper some properties of the superstring with noncommutative worldsheet are studied. We study the noncommutativity of the spacetime, generalization of the Poincar\'e symmetry of the superstring, the changes of the metric, antisymmetric tensor and dilaton.Comment: 11 pages, Latex, no figure, a new action and some references have been adde

One health: a concept led by Africa, with global benefits

Titus Mlengeya Kamani and others argue that Africa is well positioned and equipped to conduct and benefit from an integrated approac

Two Moving-Angled 1-Branes with Electric Fields in a Partially Compact Spacetime

In this article we consider two $m1$-branes at angle in the presence of the background electric fields, in a partially compact spacetime. The branes have motions along a common direction that is perpendicular to both of them. Using the boundary state formalism, we calculate their interaction amplitude. Some special cases of this interaction will be studied in detail.Comment: 10 pages, no figure, Late

Branes with Background Fields in Boundary State Formalism

Interaction of branes in presence of internal gauge fields is considered by using the boundary state formalism. This approach enables us to consider the problems that are not easily accessible to the canonical approach via open strings. The effects of compactification of some of the dimensions on tori are also discussed. Also we study the massless state contribution on this interaction.Comment: 12 pp. No figure

Mixed Branes Interaction in Compact Spacetime

We present a general description of two mixed branes interactions. For this we consider two mixed branes with dimensions p_1 and p_2, in external field B_{\mu\nu} and arbitrary gauge fields A^1_{\alpha_1} and A^2_{\alpha_2} on the world volume of them, in spacetime in which some of its directions are compactified on circles with different radii. Some examples are considered to clear these general interactions. Finally contribution of the massless states on the interactions is extracted. Closed string with mixed boundary conditions and boundary state formalism, provide useful tools for calculation of these interactions.Comment: 22 pages, to appear in Nucl. Phys.

Schwinger Effect in Non-parallel D1-branes: A Path Integral Approach

We study the Schwinger effect in a system of non-parallel D1-branes for the bosonic strings using the path integral formalism. We drive the string pair creation rate by calculating the one loop vacuum amplitude of the setup in presence of the background electric filed defined along one of the D1-branes. We find an angle dependent minimum value for the background field and show that the decaying of vacuum into string pairs takes place for the field above this value. It is shown that in $\theta\rightarrow\frac{\pi}{2}$ limit the vacuum becomes stable and thus no pair creation occurs