Related papers: Yang-Mills Action from Open Superstring Field Theo…
We study the gauge transformation of the recently computed one-loop four-point function of {\cal N}=4 supersymmetric Yang-Mills theory with gauge group U(N). The contributions from nonplanar diagrams are not gauge invariant. We compute…
Long strings emerge in many Quantum Field Theories, for example as vortices in Abelian Higgs theories, or flux tubes in Yang-Mills theories. The actions of such objects can be expanded in the number of derivatives, around a long straight…
Integrating out fast varying quantum fluctuations about Yang--Mills fields A_i and A_4, we arrive at the effective action for those fields at high temperatures. Assuming that the fields A_i and A_4 are slowly varying but that the amplitude…
We show that the four derivative terms in the effective action of three-dimensional N=8 Yang-Mills theory are determined by supersymmetry. These terms receive both perturbative and non-perturbative corrections. Using our technique for…
We introduce a nonperturbative approach to correlation functions of two determinant operators and one non-protected single-trace operator in planar N=4 supersymmetric Yang-Mills theory. Based on the gauge/string duality, we propose that…
Studies of noncommutative gauge theory have mainly focused on noncommutative spacetimes with constant noncommutative structure, with little known about actions for noncommutative 4D Yang-Mills theory beyond this case. We construct an action…
In this paper we calculate three-string interaction from light cone string field theory in pp-wave. We find exact agreements with the free planar three point functions of non-chiral BMN operators of ${\cal N} = 4$ super Yang Mills. The…
We explore the relationship between the quantum effective action and the ground state (and excited state) wave functions of a field theory. Applied to the Yang-Mills theory in 2+1 dimensions, we find the leading terms of the effective…
The paper is a brief review of the works devoted to problem of effective action in N=2 super Yang-Mills theories in harmonic superspace approach. The formulation of N=2 superfield models in harmonic superspace is discussed, background field…
Using the topological techniques developed in an earlier paper with Vafa, a field theory action is constructed for any open string with critical N=2 worldsheet superconformal invariance. Instead of the Chern-Simons-like action found by…
In the limit of large, constant B-field (the ``Seiberg-Witten limit''), the derivative expansion for open-superstring effective actions is naturally expressed in terms of the symmetric products *n. Here, we investigate corrections around…
We review the recent progress in studying the quantum structure of $6D$, ${\cal N}=(1,0)$ and ${\cal N}=(1,1)$ supersymmetric gauge theories formulated through unconstrained harmonic superfields. The harmonic superfield approach allows one…
We present an approach to $U_\star(N)$ Yang-Mills theory in non-commutative space based upon a novel phase-space analysis of the dynamical fields with additional auxiliary variables that generate Lorentz structure and colour degrees of…
We review various superspace approaches to the description of the low-energy effective action in N=4 super Yang-Mills (SYM) theory. We consider the four-derivative part of the low-energy effective action in the Coulomb branch. The typical…
One-loop effective action of noncommutative scalar field theory with cubic self-interaction is studied. Utilizing worldline formulation, both planar and nonplanar part of the effective action are computed explicitly. We find complete…
We suggest how to derive the exact (all order in $\a'$) expressions for the background fields for string solutions corresponding to gauged WZW models directly at the $2d$ field theory level. One is first to replace the classical gauged WZW…
We present the low-energy effective theory on long strings in quantum field theory, including a streamlined review of previous literature on the subject. Such long strings can appear in the form of solitonic strings, as in the 4d Abelian…
We develop N=4 d=4 bi-harmonic superspace and use it to derive a novel form for the low-energy effective action in N=4 super Yang-Mills theory. We solve the N=4 supergauge constraints in this superspace in terms of analytic superfields.…
In this Ph.D. thesis we review and elaborate on a method to find the D-brane effective action, based on BPS equations. Firstly, both for the Yang-Mills action and the Born-Infeld action it is shown that these configurations are indeed BPS,…
In previous work (Singh, 2011), we constructed an action in six dimensions using Yang-Mills fields and an auxiliary Abelian field. Here we first write down all the equations of motion and the constraints which arise from such an action.…