Fundamental Strings and D-strings in the IIB Matrix Model

Abstract

The matrix model for IIB Superstring proposed by Ishibashi, Kawai, Kitazawa and Tsuchiya is investigated. Consideration of planar and non-planar diagrams suggests that the large N perturbative expansion is consistent with the double scaling limit proposed by the above authors. We write down a Wilson loop that can be interpreted as a fundamental string vertex operator. The one point tadpole in the presence of a D-string has the right form and this can be viewed as a matrix model derivation of the boundary conditions that define a D-string. We also argue that if world sheet coordinates $\sigma$ and $\tau$ are introduced for the fundamental string, then the conjugate variable $d/d\sigma$ and $d/d\tau$ can be interpreted as the D-string world sheet coordinates. In this way the $SL(2Z)$ duality group of the IIB superstring becomes identified with the symplectic group acting on ($p,q$).

21 pages, Latex file. Two references added and two figures included

Cited by in corpus (4)

• U-duality and M-Theory
• The Hagedorn Transition and the Matrix Model for Strings
• Oscillating D-Strings from IIB Matrix Theory
• (m,n)-Strings In IIB Matrix Model