We survey on-shell and off-shell higher derivative supergravities in dimensions 1≤ D≤ 11.
Various approaches to their construction, including the Noether procedure,(harmonic) …

In this review, a number of approaches to superstring cosmology which make use of key
features which distinguish string theory from point particle theories are discussed, with …

A bstract We reformulate in Hamiltonian language the recent proposal by Hohm and
Zwiebach of an action yielding the most general O (d, d)-symmetric string cosmology …

We review some aspects of the dramatic consequences of supersymmetry breaking on
string vacua. In particular, we focus on the issue of vacuum stability in ten-dimensional string …

Starting with the two-derivative limit of D= 2 string theory, we explore the space of T-duality
invariant α′ corrections, a space that contains a point representing the fully α′-corrected …

We report two surprising results on α′ corrections in string theory restricted to massless
fields. First, for critical dimension Bianchi type I cosmologies with q scale factors only q-1 of …

A bstract The tree-level string effective action reduced from D to D− d dimensions possesses
a continuous O (d, d) symmetry, closely related to T-duality. A necessary condition for a …

We first make more precise a recent" Hamiltonian" reformulation of the Hohm-Zwiebach
approach to the tree-level, O (d, d)-invariant string cosmology equations at all orders in the …

We explore the exactly duality invariant higher-derivative extension of double field theory
due to Hohm, Siegel, and Zwiebach specialized to cosmological backgrounds. Despite …

We elaborate on the cosmological implications of the recently established non-perturbative
O (D, D)-symmetric approach. Following the α′-complete Friedmann equations, we provide …