Double field theory (DFT) is a proposal to incorporate T-duality, a distinctive symmetry of
string theory, as a symmetry of a field theory defined on a double configuration space. The …

We review the status of solitons in superstring theory, with a view to understanding the
strong coupling regime. These solitonic solutions are non-singular field configurations which …

The effective action for type II string theory compactified on a six-torus is N= 8 supergravity,
which is known to have an E7 duality symmetry. We show that this is broken by quantum …

It is pointed out that string-loop modifications of the low-energy matter couplings of the
dilation may provide a mechanism for fixing the vacuum expectation value of a massless …

We show that four-dimensional N= 2 supersymmetric SU (N) gauge theory for N> 2
necessarily contains vacua with mutually non-local massless dyons, using only analyticity of …

The dual symmetry between electric and magnetic fields is an important intrinsic property of
Maxwell equations in free space. This symmetry underlies the conservation of optical helicity …

It is argued that the type IIA 10-dimensional superstring theory is actually a compactified 11-
dimensional supermembrane theory in which the fundamental supermembrane is identified …

The general form of N= 2 supergravity coupled to an arbitrary number of vector multiplets
and hypermultiplets, with a generic gauging of the scalar manifold isometries is given. This …

We present several pieces of evidence for strong–weak coupling duality symmetry in the
heterotic string theory, compactified on a six-dimensional torus. They include symmetry of …

A bstract Relations between the various formulations of nonlinear p-form electrodynamics
with conformal-invariant weak-field and strong-field limits are clarified, with a focus on …