Related papers: 4-point effective actions in open and closed super…
I review the approach [1] to the one-loop low-energy effective action in the hypermultiplet sector for N=2 superconformal models. Any such a model contains an N=2 vector multiplet and some number of hypermultiplets. We found a general…
We present the multiloop partition function of open bosonic string theory in the presence of a constant gauge field strength, and discuss its low-energy limit. The result is written in terms of twisted determinants and differentials on…
We construct a gauge-invariant action for covariant type II string field theory in the NS-NS sector. Our construction is based on the large Hilbert space description and Zwiebach's string products are used. First, we rewrite the action for…
In this work, we study a class of higher derivative couplings in the string effective action arising at the junction of topological string theory and supersymmetric gauge theories in the $\Omega$-background. They generalise a series of…
We construct the supersymmetric completion of quartic $R+R^4$-actions in the ten-dimensional effective action of the heterotic string. Two invariants, of which the bosonic parts are known from one-loop string amplitude calculations, are…
Using the N = 2 off-shell formulation in harmonic superspace for N = 4 super Yang-Mills theory, we present a representation of the one-loop effective action which is free of so-called coinciding harmonic singularities and admits a…
$\beta$-functions for abelian and non-abelian gauge theories are studied in the regime where the large $N$ flavor expansion is applicable. The first nontrivial order in the 1/$N$ expansion is known for any value of $N\alpha$, and there are…
Two approaches concerning the connection of the fermionic kappa -- symmetry with the superstring world -- sheet superdiffeomorphism transformations are discussed. The first approach is based on the twistor -- like formulation of the…
We compare order $R^4$ terms in the 10-dimensional effective actions of SO(32) heterotic and type I superstrings from the point of view of duality between the two theories. Some of these terms do not receive higher-loop corrections being…
In this article we derive the full interacting effective actions for supersymmetric D-branes in arbitrary bosonic type II supergravity backgrounds. The actions are presented in terms of component fields up to second order in fermions. As…
Based on the recent developments of explicit computations at 2 loops in superstring theory in the covariant RNS formalism, we propose an explicit formula for the arbitrary loop 4-particle amplitude in superstring theory. We prove that this…
We gauge the abelian hierarchy of tensor fields in 4D by a Lie algebra. The resulting non-abelian tensor hierarchy can be interpreted via an equivariant chain complex. We lift this structure to N=1 superspace by constructing superfield…
We review a recent progress in constructing low-energy effective action in N=4 super Yang-Mills theories. Using harmonic superspace approach we consider N=4 SYM in terms of unconstrained N=2 superfield and apply N=2 background field method…
I review the construction of an action for open superstring field theory which does not suffer from the contact term problems of other approaches. This action resembles a Wess-Zumino-Witten action and can be constructed in a manifestly D=4…
We obtain the effective action for the bosonic string with arbitrary Yang-Mills fields, up to the \alpha' order, in general dimensions. The form of the action is determined by the requirement that the action admit well-defined Killing…
We present a combined analytical and numerical study of the effective action of field theory cosmic strings in the Abelian-Higgs model in flat space. Starting directly from the underlying solitonic field theory description, we provide a…
We review the basic results concerning the structure of effective action in N=4 supersymmetric Yang-Mills theory in Coulomb phase. Various classical formulations of this theory are considered. We show that the low-energy effective action…
We briefly review a recent progress in constructing the low-energy effective action in ${\cal N}=2,4$ super Yang-Mills theories. Using superfield methods we study the one- and two-loop contributions to the effective action in the Coulomb…
We consider a benchmark bulk theory in four-dimensions: N=2 supersymmetric QCD with the gauge group U(N) and N_f flavors of fundamental matter hypermultiplets (quarks). The nature of the BPS strings in this benchmark theory crucially…
We study the effective action of quantum mechanical SU(N) Yang-Mills theories with sixteen supersymmetries and N>2. We show that supersymmetry requires that the eight fermion terms in the supersymmetric completion of the $v^4$ terms be…