In this review we describe our current understanding of the properties of open string
tachyons on an unstable D-brane or brane–antibrane system in string theory. The various …

In this introductory review, we argue that a quantum structure of space-time naturally entails
a higher-spin theory, to avoid significant Lorentz violation. A suitable framework is provided …

A bstract It has been proposed that cobordism and K-theory groups, which can be
mathematically related in certain cases, are physically associated to generalised higher …

In this note we introduce the notion of bundle gerbe K-theory and investigate the relation to
twisted K-theory. We provide some examples. Possible applications of bundle gerbe K …

We discuss some physical issues related to the K-theoretic classification of D-brane
charges, putting an emphasis on the role of D-brane instantons. The relation to D-instantons …

In the quest for mathematical foundations of M-theory, the Hypothesis H that fluxes are
quantized in Cohomotopy theory, implies, on flat but possibly singular spacetimes, that M …

We show that one can construct D-branes in parafermionic and WZW theories (and their
orbifolds) which have very natural geometrical interpretations, and yet are not automatically …

We investigate orientifolds of type II string theory on K3 and Calabi-Yau 3-folds with
intersecting D-branes wrap** special lagrangian cycles. We determine quite generically …

We study D-branes of the SL (2, R) WZW model and of its discrete orbifolds. Gluing the
currents by group automorphisms leads to three types of D-branes: two-dimensional …

We present a small x resummation for the GLAP anomalous dimension and its
corresponding dual BFKL kernel, which includes all the available perturbative information …