Marchesini showed that the Fokker–Planck Hamiltonian for Yang-Mills theories is the loop operator. Jevicki and Rodrigues showed that the Fokker– Planck Hamiltonian of some matrix models cöıncides with temporal gauge non-critical string field theory Hamiltonians constructed by Ishibashi and Kawai (and their collaborators). Thus the loop operator for Yang–Mills theory is the temporal gauge Hamilt...

We study our Schwinger-Dyson equation as well as the large N c loop equation for supersymmetric Yang-Mills theory in four dimensions by the N = 1 superspace Wilson-loop variable. We are successful in deriving a new manifestly supersymmetric form in which a loop splitting and joining are represented by a manifestly supersymmetric as well as supergauge invariant operation in superspace. This is f...

Polyakov has conjectured that Yang–Mills theory should be equivalent to a noncritical string theory. I pointed out, based on the work of Marchesini, Ishibashi, Kawai and collaborators, and Jevicki and Rodrigues, that the loop operator of the Yang–Mills theory is the temporal gauge string field theory Hamiltonian of a noncritical string theory. In the present note I explicitly show how this work...

Conformal field theory (CFT) is important in modern particle physics in various contexts. The most powerful tool in the 2-dimensional CFT is the operator product expansion (OPE). The OPE between the energy-momentum tensor and an operator extracts its conformal weight. We find it interesting to consider the similar issue with respect to the Wilson loop in a conformally invariant Yang-Mills theor...

We report on recent progress in the use of string techniques for the computation of field theory amplitudes. We show how one–loop renormalization constants in Yang–Mills theory can be computed using the open spinning string, we review the calculation of two–loop scalar amplitudes with the bosonic string, and we briefly indicate how the technique can be applied to the two–loop vacuum bubbles of ...

Starting from tree and one-loop tachyon amplitudes of open string theory in the presence of a constant B-field, we explore two problems. First we show that in the noncommutative field theory limit the amplitudes reduce to tree and one-loop diagrams of the noncommutative Φ theory. Next, we check factorization of the one-loop amplitudes in the long cylinder limit. PACS : 11.25.-w, 11.25.Db

We calculate the two-loop β-functions for soft supersymmetry-breaking interactions in a general supersymmetric gauge theory, emphasising the role of the evanescent couplings and masses that are generic to a non-supersymmetric theory. We also show that a simple set of conditions sufficient for one-loop finiteness renders a theory two-loop finite, and we speculate on the possible significance of ...

We study the connection between the Goodwillie tower of the identity and the lower central series of the loop group on connected spaces. We define the simplicial theory of homotopy n-nilpotent groups. This notion interpolates between infinite loop spaces and loop spaces. We prove, that the set-valued algebraic theory obtained by applying π0 is the theory of ordinary n-nilpotent groups. Finally ...

We study loop corrections in boundary string field theory (BSFT). After commenting on problems with quantizing the tree level BSFT as an ordinary field theory, we discuss the tree level coupling to closed strings and define the loop corrections via factorization in the closed string channel. This description is weakly coupled in the vicinity of the closed string vacuum. Our proposal for the one...

We construct vortex loop operators in the three-dimensional N = 6 supersymmetric Chern-Simons theory recently constructed by Aharony, Bergman, Jafferis and Maldacena. These disorder loop operators are specified by a vortex-like singularity for the scalar and gauge fields along a one dimensional curve in spacetime. We identify the 1/2, 1/3 and 1/6 BPS loop operators in the Chern-Simons theory wi...